diff --git a/backup/moodle2/restore_subplugin.class.php b/backup/moodle2/restore_subplugin.class.php
index 640968b88afbb..c848219ccf867 100644
--- a/backup/moodle2/restore_subplugin.class.php
+++ b/backup/moodle2/restore_subplugin.class.php
@@ -87,6 +87,23 @@ public function launch_after_execute_methods() {
         }
     }
 
+    /**
+     * The after_restore dispatcher for any restore_subplugin class.
+     *
+     * This method will dispatch execution to the corresponding
+     * after_restore_xxx() method when available, with xxx
+     * being the connection point of the instance, so subplugin
+     * classes with multiple connection points will support
+     * multiple after_restore methods, one for each connection point.
+     */
+    public function launch_after_restore_methods() {
+        // Check if the after_restore method exists and launch it.
+        $afterestore = 'after_restore_' . basename($this->connectionpoint->get_path());
+        if (method_exists($this, $afterestore)) {
+            $this->$afterestore();
+        }
+    }
+
 // Protected API starts here
 
 // restore_step/structure_step/task wrappers
diff --git a/lib/classes/plugin_manager.php b/lib/classes/plugin_manager.php
index 302e5363dbf83..cb6c2fe2899fb 100644
--- a/lib/classes/plugin_manager.php
+++ b/lib/classes/plugin_manager.php
@@ -1804,7 +1804,7 @@ public static function standard_plugins_list($type) {
             ),
 
             'ltiservice' => array(
-                'memberships', 'profile', 'toolproxy', 'toolsettings'
+                'gradebookservices', 'memberships', 'profile', 'toolproxy', 'toolsettings'
             ),
 
             'mlbackend' => array(
diff --git a/mod/lti/classes/local/ltiservice/resource_base.php b/mod/lti/classes/local/ltiservice/resource_base.php
index 4d617fe1f2120..1fdb72ec76667 100644
--- a/mod/lti/classes/local/ltiservice/resource_base.php
+++ b/mod/lti/classes/local/ltiservice/resource_base.php
@@ -28,6 +28,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
+global $CFG;
 require_once($CFG->dirroot . '/mod/lti/locallib.php');
 
 
@@ -41,7 +42,16 @@
  */
 abstract class resource_base {
 
-    /** @var object Service associated with this resource. */
+    /**  HTTP Post method */
+    const HTTP_POST = 'POST';
+    /**  HTTP Get method */
+    const HTTP_GET = 'GET';
+    /**  HTTP Put method */
+    const HTTP_PUT = 'PUT';
+    /**  HTTP Delete method */
+    const HTTP_DELETE = 'DELETE';
+
+    /** @var service_base Service associated with this resource. */
     private $service;
     /** @var string Type for this resource. */
     protected $type;
@@ -62,7 +72,7 @@ abstract class resource_base {
     /**
      * Class constructor.
      *
-     * @param mod_lti\local\ltiservice\service_base $service Service instance
+     * @param service_base $service Service instance
      */
     public function __construct($service) {
 
@@ -125,7 +135,7 @@ public function get_type() {
     /**
      * Get the resource's service.
      *
-     * @return mod_lti\local\ltiservice\service_base
+     * @return mixed
      */
     public function get_service() {
 
@@ -190,7 +200,7 @@ public function get_endpoint() {
     /**
      * Execute the request for this resource.
      *
-     * @param mod_lti\local\ltiservice\response $response  Response object for this request.
+     * @param response $response  Response object for this request.
      */
     public abstract function execute($response);
 
@@ -224,7 +234,7 @@ public function check_tool_proxy($toolproxyguid, $body = null) {
                     }
                 }
                 if (!$ok) {
-                    debugging('Requested service not included in tool proxy: ' . $this->get_id());
+                    debugging('Requested service not included in tool proxy: ' . $this->get_id(), DEBUG_DEVELOPER);
                 }
             }
         }
@@ -233,6 +243,45 @@ public function check_tool_proxy($toolproxyguid, $body = null) {
 
     }
 
+    /**
+     * Check to make sure the request is valid.
+     *
+     * @param int $typeid                   The typeid we want to use
+     * @param int $contextid                The course we are at
+     * @param string $permissionrequested   The permission to be checked
+     * @param string $body                  Body of HTTP request message
+     *
+     * @return boolean
+     */
+    public function check_type($typeid, $contextid, $permissionrequested, $body = null) {
+        $ok = false;
+        if ($this->get_service()->check_type($typeid, $contextid, $body)) {
+            $neededpermissions = $this->get_permissions($typeid);
+            foreach ($neededpermissions as $permission) {
+                if ($permission == $permissionrequested) {
+                    $ok = true;
+                    break;
+                }
+            }
+            if (!$ok) {
+                debugging('Requested service ' . $permissionrequested . ' not included in tool type: ' . $typeid,
+                    DEBUG_DEVELOPER);
+            }
+        }
+        return $ok;
+
+    }
+
+    /**
+     * get permissions from the config of the tool for that resource
+     *
+     * @param int $ltitype Type of LTI
+     * @return array with the permissions related to this resource by the $ltitype or empty if none.
+     */
+    public function get_permissions($ltitype) {
+        return array();
+    }
+
     /**
      * Parse a value for custom parameter substitution variables.
      *
diff --git a/mod/lti/classes/local/ltiservice/response.php b/mod/lti/classes/local/ltiservice/response.php
index 5029d216acedb..8f4bcabcd2e8e 100644
--- a/mod/lti/classes/local/ltiservice/response.php
+++ b/mod/lti/classes/local/ltiservice/response.php
@@ -54,6 +54,8 @@ class response {
     private $body;
     /** @var array HTTP response codes. */
     private $responsecodes;
+    /** @var array HTTP additional headers. */
+    private $additionalheaders;
 
     /**
      * Class constructor.
@@ -83,6 +85,7 @@ public function __construct() {
             500 => 'Internal Server Error',
             501 => 'Not Implemented'
         );
+        $this->additionalheaders = array();
 
     }
 
@@ -202,11 +205,23 @@ public function set_body($body) {
         $this->body = $body;
     }
 
+    /**
+     * Add an additional header.
+     *
+     * @param string $header The new header
+     */
+    public function add_additional_header($header) {
+        array_push($this->additionalheaders, $header);
+    }
+
     /**
      * Send the response.
      */
     public function send() {
         header("HTTP/1.0 {$this->code} {$this->get_reason()}");
+        foreach ($this->additionalheaders as $header) {
+            header($header);
+        }
         if (($this->code >= 200) && ($this->code < 300)) {
             if (!empty($this->contenttype)) {
                 header("Content-Type: {$this->contenttype};charset=UTF-8");
diff --git a/mod/lti/classes/local/ltiservice/service_base.php b/mod/lti/classes/local/ltiservice/service_base.php
index 73726bd4e224e..26a89c1bcd8a5 100644
--- a/mod/lti/classes/local/ltiservice/service_base.php
+++ b/mod/lti/classes/local/ltiservice/service_base.php
@@ -28,11 +28,13 @@
 
 defined('MOODLE_INTERNAL') || die();
 
+global $CFG;
 require_once($CFG->dirroot . '/mod/lti/locallib.php');
 require_once($CFG->dirroot . '/mod/lti/OAuthBody.php');
 
 // TODO: Switch to core oauthlib once implemented - MDL-30149.
 use moodle\mod\lti as lti;
+use stdClass;
 
 
 /**
@@ -133,10 +135,80 @@ public function set_tool_proxy($toolproxy) {
     /**
      * Get the resources for this service.
      *
-     * @return array
+     * @return resource_base[]
      */
     abstract public function get_resources();
 
+    /**
+     * Returns the configuration options for this service.
+     *
+     * @param \MoodleQuickForm $mform Moodle quickform object definition
+     */
+    public function get_configuration_options(&$mform) {
+
+    }
+
+    /**
+     * Return an array with the names of the parameters that the service will be saving in the configuration
+     *
+     * @return array  Names list of the parameters that the service will be saving in the configuration
+     */
+    public function get_configuration_parameter_names() {
+        return array();
+    }
+
+    /**
+     * Default implementation will check for the existence of at least one mod_lti entry for that tool and context.
+     *
+     * It may be overridden if other inferences can be done.
+     *
+     * Ideally a Site Tool should be explicitly engaged with a course, the check on the presence of a link is a proxy
+     * to infer a Site Tool engagement until an explicit Site Tool - Course relationship exists.
+     *
+     * @param int $typeid The tool lti type id.
+     * @param int $courseid The course id.
+     * @return bool returns True if tool is used in context, false otherwise.
+     */
+    public function is_used_in_context($typeid, $courseid) {
+        global $DB;
+
+        $ok = $DB->record_exists('lti', array('course' => $courseid, 'typeid' => $typeid));
+        return $ok || $DB->record_exists('lti_types', array('course' => $courseid, 'id' => $typeid));
+    }
+
+    /**
+     * Checks if there is a site tool or a course tool for this site.
+     *
+     * @param int $typeid The tool lti type id.
+     * @param int $courseid The course id.
+     * @return bool returns True if tool is allowed in context, false otherwise.
+     */
+    public function is_allowed_in_context($typeid, $courseid) {
+        global $DB;
+
+        // Check if it is a Course tool for this course or a Site tool.
+        $type = $DB->get_record('lti_types', array('id' => $typeid));
+
+        return $type && ($type->course == $courseid || $type->course == SITEID);
+    }
+
+    /**
+     * Return an array of key/values to add to the launch parameters.
+     *
+     * @param string $messagetype  'basic-lti-launch-request' or 'ContentItemSelectionRequest'.
+     * @param string $courseid     The course id.
+     * @param string $userid       The user id.
+     * @param string $typeid       The tool lti type id.
+     * @param string $modlti       The id of the lti activity.
+     *
+     * The type is passed to check the configuration and not return parameters for services not used.
+     *
+     * @return array Key/value pairs to add as launch parameters.
+     */
+    public function get_launch_parameters($messagetype, $courseid, $userid, $typeid, $modlti = null) {
+        return array();
+    }
+
     /**
      * Get the path for service requests.
      *
@@ -202,9 +274,35 @@ public function check_tool_proxy($toolproxyguid, $body = null) {
         if ($ok) {
             $this->toolproxy = $toolproxy;
         }
-
         return $ok;
+    }
 
+    /**
+     * Check that the request has been properly signed.
+     *
+     * @param int $typeid The tool id
+     * @param int $courseid The course we are at
+     * @param string $body Request body (null if none)
+     *
+     * @return bool
+     */
+    public function check_type($typeid, $courseid, $body = null) {
+        $ok = false;
+        $tool = null;
+        $consumerkey = lti\get_oauth_key_from_headers();
+        if (empty($typeid)) {
+            return $ok;
+        } else if ($this->is_allowed_in_context($typeid, $courseid)) {
+            $tool = lti_get_type_type_config($typeid);
+            if ($tool !== false) {
+                if (!$this->is_unsigned() && ($tool->lti_resourcekey == $consumerkey)) {
+                    $ok = $this->check_signature($tool->lti_resourcekey, $tool->lti_password, $body);
+                } else {
+                    $ok = $this->is_unsigned();
+                }
+            }
+        }
+        return $ok;
     }
 
     /**
diff --git a/mod/lti/edit_form.php b/mod/lti/edit_form.php
index 8db9ca53c95c7..5e618dec0f2d1 100644
--- a/mod/lti/edit_form.php
+++ b/mod/lti/edit_form.php
@@ -49,10 +49,24 @@
 
 defined('MOODLE_INTERNAL') || die;
 
+global $CFG;
 require_once($CFG->libdir.'/formslib.php');
 require_once($CFG->dirroot.'/mod/lti/locallib.php');
 
-class mod_lti_edit_types_form extends moodleform{
+/**
+ * LTI Edit Form
+ *
+ * @package    mod_lti
+ * @copyright  2009 Marc Alier, Jordi Piguillem, Nikolas Galanis
+ *  marc.alier@upc.edu
+ * @copyright  2009 Universitat Politecnica de Catalunya http://www.upc.edu
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class mod_lti_edit_types_form extends moodleform {
+
+    /**
+     * Define this form.
+     */
     public function definition() {
         global $CFG;
 
@@ -147,6 +161,16 @@ public function definition() {
             $mform->disabledIf('lti_contentitem', null);
         }
 
+        $mform->addElement('text', 'lti_toolurl_ContentItemSelectionRequest',
+            get_string('toolurl_contentitemselectionrequest', 'lti'), array('size' => '64'));
+        $mform->setType('lti_toolurl_ContentItemSelectionRequest', PARAM_URL);
+        $mform->setAdvanced('lti_toolurl_ContentItemSelectionRequest');
+        $mform->addHelpButton('lti_toolurl_ContentItemSelectionRequest', 'toolurl_contentitemselectionrequest', 'lti');
+        $mform->disabledIf('lti_toolurl_ContentItemSelectionRequest', 'lti_contentitem', 'notchecked');
+        if ($istool) {
+            $mform->disabledIf('lti_toolurl__ContentItemSelectionRequest', null);
+        }
+
         $mform->addElement('hidden', 'oldicon');
         $mform->setType('oldicon', PARAM_URL);
 
@@ -160,6 +184,11 @@ public function definition() {
         $mform->setAdvanced('lti_secureicon');
         $mform->addHelpButton('lti_secureicon', 'secure_icon_url', 'lti');
 
+        if (!$istool) {
+            // Display the lti advantage services.
+            $this->get_lti_advantage_services($mform);
+        }
+
         if (!$istool) {
             // Add privacy preferences fieldset where users choose whether to send their data.
             $mform->addElement('header', 'privacy', get_string('privacy', 'lti'));
@@ -253,4 +282,19 @@ public function get_data() {
         }
         return $data;
     }
+
+    /**
+     * Generates the lti advantage extra configuration adding it to the mform
+     *
+     * @param MoodleQuickForm $mform
+     */
+    public function get_lti_advantage_services(&$mform) {
+        // For each service add the label and get the array of configuration.
+        $services = lti_get_services();
+        $mform->addElement('header', 'services', get_string('services', 'lti'));
+        foreach ($services as $service) {
+            /** @var \mod_lti\local\ltiservice\service_base $service */
+            $service->get_configuration_options($mform);
+        }
+    }
 }
diff --git a/mod/lti/lang/en/lti.php b/mod/lti/lang/en/lti.php
index 11391c1ce8855..12e68000f18d5 100644
--- a/mod/lti/lang/en/lti.php
+++ b/mod/lti/lang/en/lti.php
@@ -510,9 +510,10 @@
 If two different tool configurations are for the same domain, the most specific match will be used.
 
 You can also insert a cartridge URL if you have one and the details for the tool will be automatically filled.';
+$string['toolurl_contentitemselectionrequest'] = 'Content Selection URL';
+$string['toolurl_contentitemselectionrequest_help'] = 'The Content Selection URL will be used to launch the content selection page from the tool provider. If it is empty, the Tool URL will be used';
 $string['typename'] = 'Tool name';
-$string['typename_help'] = 'The tool name is used to identify the tool provider within Moodle. The name entered will be visible
-to teachers when adding external tools within courses.';
+$string['typename_help'] = 'The tool name is used to identify the tool provider within Moodle. The name entered will be visible to teachers when adding external tools within courses.';
 $string['types'] = 'Types';
 $string['unabletocreatetooltype'] = 'Unable to create tool';
 $string['unabletofindtooltype'] = 'Unable to find tool for {$a->id}';
diff --git a/mod/lti/locallib.php b/mod/lti/locallib.php
index 13ca7c5bc5f92..b501b2cf7cdff 100644
--- a/mod/lti/locallib.php
+++ b/mod/lti/locallib.php
@@ -53,6 +53,7 @@
 // TODO: Switch to core oauthlib once implemented - MDL-30149.
 use moodle\mod\lti as lti;
 
+global $CFG;
 require_once($CFG->dirroot.'/mod/lti/OAuth.php');
 require_once($CFG->libdir.'/weblib.php');
 require_once($CFG->dirroot . '/course/modlib.php');
@@ -96,7 +97,7 @@
  * @since  Moodle 3.0
  */
 function lti_get_launch_data($instance) {
-    global $PAGE, $CFG;
+    global $PAGE, $CFG, $USER;
 
     if (empty($instance->typeid)) {
         $tool = lti_get_tool_by_url_match($instance->toolurl, $instance->course);
@@ -230,6 +231,18 @@ function lti_get_launch_data($instance) {
 
     $requestparams['launch_presentation_return_url'] = $returnurl;
 
+    // Add the parameters configured by the LTI advantage services.
+    if ($typeid && !$islti2) {
+        $services = lti_get_services();
+        foreach ($services as $service) {
+            $ltiadvantageparameters = $service->get_launch_parameters('basic-lti-launch-request',
+                    $course->id, $USER->id , $typeid, $instance->id);
+            foreach ($ltiadvantageparameters as $ltiadvantagekey => $ltiadvantagevalue) {
+                $requestparams[$ltiadvantagekey] = $ltiadvantagevalue;
+            }
+        }
+    }
+
     // Allow request params to be updated by sub-plugins.
     $plugins = core_component::get_plugin_list('ltisource');
     foreach (array_keys($plugins) as $plugin) {
@@ -284,7 +297,7 @@ function lti_launch_tool($instance) {
 /**
  * Prepares an LTI registration request message
  *
- * $param object $instance       Tool Proxy instance object
+ * @param object $toolproxy  Tool Proxy instance object
  */
 function lti_register($toolproxy) {
     $endpoint = $toolproxy->regurl;
@@ -617,6 +630,8 @@ function lti_build_custom_parameters($toolproxy, $tool, $instance, $params, $cus
 function lti_build_content_item_selection_request($id, $course, moodle_url $returnurl, $title = '', $text = '', $mediatypes = [],
                                                   $presentationtargets = [], $autocreate = false, $multiple = false,
                                                   $unsigned = false, $canconfirm = false, $copyadvice = false) {
+    global $USER;
+
     $tool = lti_get_type($id);
     // Validate parameters.
     if (!$tool) {
@@ -693,6 +708,18 @@ function lti_build_content_item_selection_request($id, $course, moodle_url $retu
         $requestparams = array_merge($requestparams, $lti2params);
     }
 
+    // Add the parameters configured by the LTI advantage services.
+    if ($id && !$islti2) {
+        $services = lti_get_services();
+        foreach ($services as $service) {
+            $ltiadvantageparameters = $service->get_launch_parameters('ContentItemSelectionRequest',
+                    $course->id, $USER->id , $id);
+            foreach ($ltiadvantageparameters as $ltiadvantagekey => $ltiadvantagevalue) {
+                $requestparams[$ltiadvantagekey] = $ltiadvantagevalue;
+            }
+        }
+    }
+
     // Get standard request parameters and merge to the request parameters.
     $orgid = !empty($typeconfig['organizationid']) ? $typeconfig['organizationid'] : '';
     $standardparams = lti_build_standard_request(null, $orgid, $islti2, 'ContentItemSelectionRequest');
@@ -856,9 +883,6 @@ function lti_tool_configuration_from_content_item($typeid, $messagetype, $ltiver
     if (empty($items)) {
         throw new moodle_exception('errorinvaliddata', 'mod_lti', '', $contentitemsjson);
     }
-    if ($items->{'@context'} !== 'http://purl.imsglobal.org/ctx/lti/v1/ContentItem') {
-        throw new moodle_exception('errorinvalidmediatype', 'mod_lti', '', $items->{'@context'});
-    }
     if (!isset($items->{'@graph'}) || !is_array($items->{'@graph'}) || (count($items->{'@graph'}) > 1)) {
         throw new moodle_exception('errorinvalidresponseformat', 'mod_lti');
     }
@@ -922,7 +946,7 @@ function lti_tool_configuration_from_content_item($typeid, $messagetype, $ltiver
 }
 
 function lti_get_tool_table($tools, $id) {
-    global $CFG, $OUTPUT, $USER;
+    global $OUTPUT;
     $html = '';
 
     $typename = get_string('typename', 'lti');
@@ -1124,9 +1148,9 @@ function lti_get_tool_proxy_table($toolproxies, $id) {
 /**
  * Extracts the enabled capabilities into an array, including those implicitly declared in a parameter
  *
- * @param object    $tool           Tool instance object
+ * @param object $tool  Tool instance object
  *
- * @return Array of enabled capabilities
+ * @return array List of enabled capabilities
  */
 function lti_get_enabled_capabilities($tool) {
     if (!isset($tool)) {
@@ -1224,10 +1248,11 @@ function lti_get_custom_parameters($toolproxy, $tool, $params, $parameters) {
  * @param string    $value          Custom parameter value
  * @param boolean   $islti2         True if an LTI 2 tool is being launched
  *
- * @return Parsed value of custom parameter
+ * @return string Parsed value of custom parameter
  */
 function lti_parse_custom_parameter($toolproxy, $tool, $params, $value, $islti2) {
-    global $USER, $COURSE;
+    // This is required as {${$valarr[0]}->{$valarr[1]}}" may be using the USER var.
+    global $USER;
 
     if ($value) {
         if (substr($value, 0, 1) == '\\') {
@@ -1403,8 +1428,6 @@ function lti_get_tools_by_url($url, $state, $courseid = null) {
 function lti_get_tools_by_domain($domain, $state = null, $courseid = null) {
     global $DB, $SITE;
 
-    $filters = array('tooldomain' => $domain);
-
     $statefilter = '';
     $coursefilter = '';
 
@@ -1433,6 +1456,9 @@ function lti_get_tools_by_domain($domain, $state = null, $courseid = null) {
 /**
  * Returns all basicLTI tools configured by the administrator
  *
+ * @param int $course
+ *
+ * @return array
  */
 function lti_filter_get_types($course) {
     global $DB;
@@ -1698,7 +1724,7 @@ function lti_delete_type($id) {
 function lti_set_state_for_type($id, $state) {
     global $DB;
 
-    $DB->update_record('lti_types', array('id' => $id, 'state' => $state));
+    $DB->update_record('lti_types', (object)array('id' => $id, 'state' => $state));
 }
 
 /**
@@ -1709,7 +1735,6 @@ function lti_set_state_for_type($id, $state) {
  * @return array Basic LTI configuration details
  */
 function lti_get_config($ltiobject) {
-    $typeconfig = array();
     $typeconfig = (array)$ltiobject;
     $additionalconfig = lti_get_type_config($ltiobject->typeid);
     $typeconfig = array_merge($typeconfig, $additionalconfig);
@@ -1722,7 +1747,7 @@ function lti_get_config($ltiobject) {
  *
  * @param int $id
  *
- * @return Instance configuration
+ * @return object configuration
  *
  */
 function lti_get_type_config_from_instance($id) {
@@ -1760,7 +1785,7 @@ function lti_get_type_config_from_instance($id) {
  *
  * @param int $id
  *
- * @return Configuration details
+ * @return stdClass Configuration details
  */
 function lti_get_type_type_config($id) {
     global $DB;
@@ -1847,6 +1872,10 @@ function lti_get_type_type_config($id) {
         $type->lti_contentitem = $config['contentitem'];
     }
 
+    if (isset($config['toolurl_ContentItemSelectionRequest'])) {
+        $type->lti_toolurl_ContentItemSelectionRequest = $config['toolurl_ContentItemSelectionRequest'];
+    }
+
     if (isset($config['debuglaunch'])) {
         $type->lti_debuglaunch = $config['debuglaunch'];
     }
@@ -1855,6 +1884,19 @@ function lti_get_type_type_config($id) {
         $type->lti_module_class_type = $config['module_class_type'];
     }
 
+    // Get the parameters from the LTI services.
+    $services = lti_get_services();
+    $ltiserviceprefixlength = 11;
+    foreach ($services as $service) {
+        $configurationparameters = $service->get_configuration_parameter_names();
+        foreach ($configurationparameters as $ltiserviceparameter) {
+            $shortltiserviceparameter = substr($ltiserviceparameter, $ltiserviceprefixlength);
+            if (isset($config[$shortltiserviceparameter])) {
+                $type->$ltiserviceparameter = $config[$shortltiserviceparameter];
+            }
+        }
+    }
+
     return $type;
 }
 
@@ -1886,6 +1928,14 @@ function lti_prepare_type_for_save($type, $config) {
         $type->contentitem = !empty($config->lti_contentitem) ? $config->lti_contentitem : 0;
         $config->lti_contentitem = $type->contentitem;
     }
+    if (isset($config->lti_toolurl_ContentItemSelectionRequest)) {
+        if (!empty($config->lti_toolurl_ContentItemSelectionRequest)) {
+            $type->toolurl_ContentItemSelectionRequest = $config->lti_toolurl_ContentItemSelectionRequest;
+        } else {
+            $type->toolurl_ContentItemSelectionRequest = '';
+        }
+        $config->lti_toolurl_ContentItemSelectionRequest = $type->toolurl_ContentItemSelectionRequest;
+    }
 
     $type->timemodified = time();
 
@@ -1901,7 +1951,6 @@ function lti_update_type($type, $config) {
 
     lti_prepare_type_for_save($type, $config);
 
-    $clearcache = false;
     if (lti_request_is_using_ssl() && !empty($type->secureicon)) {
         $clearcache = !isset($config->oldicon) || ($config->oldicon !== $type->secureicon);
     } else {
@@ -1918,6 +1967,13 @@ function lti_update_type($type, $config) {
                 $record->value = $value;
                 lti_update_config($record);
             }
+            if (substr($key, 0, 11) == 'ltiservice_' && !is_null($value)) {
+                $record = new \StdClass();
+                $record->typeid = $type->id;
+                $record->name = substr($key, 11);
+                $record->value = $value;
+                lti_update_config($record);
+            }
         }
         require_once($CFG->libdir.'/modinfolib.php');
         if ($clearcache) {
@@ -1964,10 +2020,17 @@ function lti_add_type($type, $config) {
 
     if ($id) {
         foreach ($config as $key => $value) {
-            if (substr($key, 0, 4) == 'lti_' && !is_null($value)) {
+            if (!is_null($value)) {
+                $fieldparts = preg_split("/(lti|ltiservice)_/i", $key);
+                // If array has only one element, it did not start with the pattern.
+                if (count($fieldparts) < 2) {
+                    continue;
+                }
+                $fieldname = $fieldparts[1];
+
                 $record = new \StdClass();
                 $record->typeid = $id;
-                $record->name = substr($key, 4);
+                $record->name = $fieldname;
                 $record->value = $value;
 
                 lti_add_config($record);
@@ -2033,7 +2096,7 @@ function lti_get_tool_proxies_from_registration_url($regurl) {
  *
  * @param int $id
  *
- * @return Tool Proxy details
+ * @return mixed Tool Proxy details
  */
 function lti_get_tool_proxy($id) {
     global $DB;
@@ -2052,7 +2115,6 @@ function lti_get_tool_proxies($orphanedonly) {
     global $DB;
 
     if ($orphanedonly) {
-        $tools = $DB->get_records('lti_types');
         $usedproxyids = array_values($DB->get_fieldset_select('lti_types', 'toolproxyid', 'toolproxyid IS NOT NULL'));
         $proxies = $DB->get_records('lti_tool_proxies', null, 'state DESC, timemodified DESC');
         foreach ($proxies as $key => $value) {
@@ -2071,7 +2133,7 @@ function lti_get_tool_proxies($orphanedonly) {
  *
  * @param int $id
  *
- * @return Tool Proxy details
+ * @return mixed  Tool Proxy details
  */
 function lti_get_tool_proxy_config($id) {
     $toolproxy = lti_get_tool_proxy($id);
@@ -2190,12 +2252,11 @@ function lti_add_config($config) {
  *
  * @param object  $config   Tool configuration
  *
- * @return Record id number
+ * @return mixed Record id number
  */
 function lti_update_config($config) {
     global $DB;
 
-    $return = true;
     $old = $DB->get_record('lti_types_config', array('typeid' => $config->typeid, 'name' => $config->name));
 
     if ($old) {
@@ -2243,7 +2304,7 @@ function lti_set_tool_settings($settings, $toolproxyid, $courseid = null, $insta
     $record = $DB->get_record('lti_tool_settings', array('toolproxyid' => $toolproxyid,
         'course' => $courseid, 'coursemoduleid' => $instanceid));
     if ($record !== false) {
-        $DB->update_record('lti_tool_settings', array('id' => $record->id, 'settings' => $json, 'timemodified' => time()));
+        $DB->update_record('lti_tool_settings', (object)array('id' => $record->id, 'settings' => $json, 'timemodified' => time()));
     } else {
         $record = new \stdClass();
         $record->toolproxyid = $toolproxyid;
@@ -2259,11 +2320,12 @@ function lti_set_tool_settings($settings, $toolproxyid, $courseid = null, $insta
 /**
  * Signs the petition to launch the external tool using OAuth
  *
- * @param $oldparms     Parameters to be passed for signing
- * @param $endpoint     url of the external tool
- * @param $method       Method for sending the parameters (e.g. POST)
- * @param $oauth_consumoer_key          Key
- * @param $oauth_consumoer_secret       Secret
+ * @param array  $oldparms     Parameters to be passed for signing
+ * @param string $endpoint     url of the external tool
+ * @param string $method       Method for sending the parameters (e.g. POST)
+ * @param string $oauthconsumerkey
+ * @param string $oauthconsumersecret
+ * @return array|null
  */
 function lti_sign_parameters($oldparms, $endpoint, $method, $oauthconsumerkey, $oauthconsumersecret) {
 
@@ -2285,9 +2347,10 @@ function lti_sign_parameters($oldparms, $endpoint, $method, $oauthconsumerkey, $
 /**
  * Posts the launch petition HTML
  *
- * @param $newparms     Signed parameters
- * @param $endpoint     URL of the external tool
- * @param $debug        Debug (true/false)
+ * @param array $newparms   Signed parameters
+ * @param string $endpoint  URL of the external tool
+ * @param bool $debug       Debug (true/false)
+ * @return string
  */
 function lti_post_launch_html($newparms, $endpoint, $debug=false) {
     $r = "<form action=\"" . $endpoint .
@@ -2607,7 +2670,7 @@ function lti_get_services() {
  *
  * @param string $servicename Name of service
  *
- * @return mod_lti\local\ltiservice\service_base Service
+ * @return bool|\mod_lti\local\ltiservice\service_base Service
  */
 function lti_get_service_by_name($servicename) {
 
@@ -2624,7 +2687,7 @@ function lti_get_service_by_name($servicename) {
 /**
  * Finds a service by id
  *
- * @param array  $services    Array of services
+ * @param \mod_lti\local\ltiservice\service_base[] $services Array of services
  * @param string $resourceid  ID of resource
  *
  * @return mod_lti\local\ltiservice\service_base Service
@@ -2742,15 +2805,14 @@ function get_tool_proxy_edit_url(stdClass $proxy) {
  *
  * @param stdClass $type The tool type
  *
- * @return string|void The url to the course of the tool type, void if it is a site wide type
+ * @return string The url to the course of the tool type, void if it is a site wide type
  */
 function get_tool_type_course_url(stdClass $type) {
-    if ($type->course == 1) {
-        return;
-    } else {
+    if ($type->course != 1) {
         $url = new moodle_url('/course/view.php', array('id' => $type->course));
         return $url->out();
     }
+    return null;
 }
 
 /**
@@ -2758,7 +2820,7 @@ function get_tool_type_course_url(stdClass $type) {
  *
  * @param stdClass $type The tool type
  *
- * @return string The urls of the tool type
+ * @return array The urls of the tool type
  */
 function get_tool_type_urls(stdClass $type) {
     $courseurl = get_tool_type_course_url($type);
@@ -2780,7 +2842,7 @@ function get_tool_type_urls(stdClass $type) {
  *
  * @param stdClass $proxy The tool proxy
  *
- * @return string The urls of the tool proxy
+ * @return array The urls of the tool proxy
  */
 function get_tool_proxy_urls(stdClass $proxy) {
     global $OUTPUT;
@@ -2802,7 +2864,6 @@ function get_tool_proxy_urls(stdClass $proxy) {
  * pending, configured, rejected, unknown
  */
 function get_tool_type_state_info(stdClass $type) {
-    $state = '';
     $isconfigured = false;
     $ispending = false;
     $isrejected = false;
diff --git a/mod/lti/service/gradebookservices/backup/moodle2/backup_ltiservice_gradebookservices_subplugin.class.php b/mod/lti/service/gradebookservices/backup/moodle2/backup_ltiservice_gradebookservices_subplugin.class.php
new file mode 100644
index 0000000000000..b53168f84e000
--- /dev/null
+++ b/mod/lti/service/gradebookservices/backup/moodle2/backup_ltiservice_gradebookservices_subplugin.class.php
@@ -0,0 +1,137 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains the class for restore of this gradebookservices plugin
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+
+require_once($CFG->dirroot.'/mod/lti/locallib.php');
+
+/**
+ * Provides the information to backup gradebookservices lineitems
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class backup_ltiservice_gradebookservices_subplugin extends backup_subplugin {
+
+    /** TypeId contained in DB but is invalid */
+    const NONVALIDTYPEID = 0;
+
+    /**
+     * Returns the subplugin information to attach to submission element
+     * @return backup_subplugin_element
+     */
+    protected function define_lti_subplugin_structure() {
+        global $DB;
+
+        // Create XML elements.
+        $subplugin = $this->get_subplugin_element();
+        $subpluginwrapper = new backup_nested_element($this->get_recommended_name());
+        // The gbs entries related with this element.
+        $lineitems = new backup_nested_element('lineitems');
+        $lineitem = new backup_nested_element('lineitem', array('id'), array(
+                'gradeitemid',
+                'courseid',
+                'toolproxyid',
+                'typeid',
+                'baseurl',
+                'ltilinkid',
+                'tag',
+                'vendorcode',
+                'guid'
+                )
+        );
+
+        // Build the tree.
+        $subplugin->add_child($subpluginwrapper);
+        $subpluginwrapper->add_child($lineitems);
+        $lineitems->add_child($lineitem);
+
+        // We need to know the actual activity tool or toolproxy.
+        // If and activity is assigned to a type that doesn't exists we don't want to backup any related lineitems.``
+        // Default to invalid condition.
+        $typeid = 0;
+        $toolproxyid = '0';
+
+        /* cache parent property to account for missing PHPDoc type specification */
+        /** @var backup_activity_task $activitytask */
+        $activitytask = $this->task;
+        $activityid = $activitytask->get_activityid();
+        $activitycourseid = $activitytask->get_courseid();
+        $lti = $DB->get_record('lti', ['id' => $activityid], 'typeid, toolurl, securetoolurl');
+        $ltitype = $DB->get_record('lti_types', ['id' => $lti->typeid], 'toolproxyid, baseurl');
+        if ($ltitype) {
+            $typeid = $lti->typeid;
+            $toolproxyid = $ltitype->toolproxyid;
+        } else if ($lti->typeid == self::NONVALIDTYPEID) { // This activity comes from an old backup.
+            // 1. Let's check if the activity is coupled. If so, find the values in the GBS element.
+            $gbsrecord = $DB->get_record('ltiservice_gradebookservices',
+                    ['ltilinkid' => $activityid], 'typeid,toolproxyid,baseurl');
+            if ($gbsrecord) {
+                $typeid = $gbsrecord->typeid;
+                $toolproxyid = $gbsrecord->toolproxyid;
+            } else { // 2. If it is uncoupled... we will need to guess the right activity typeid
+                // Guess the typeid for the activity.
+                $tool = lti_get_tool_by_url_match($lti->toolurl, $activitycourseid);
+                if (!$tool) {
+                    $tool = lti_get_tool_by_url_match($lti->securetoolurl, $activitycourseid);
+                }
+                if ($tool) {
+                    $alttypeid = $tool->id;
+                    // If we have a valid typeid then get types again.
+                    if ($alttypeid != self::NONVALIDTYPEID) {
+                        $ltitype = $DB->get_record('lti_types', ['id' => $alttypeid], 'toolproxyid, baseurl');
+                        $toolproxyid = $ltitype->toolproxyid;
+                    }
+                }
+            }
+        }
+
+        // Define sources.
+        if ($toolproxyid != null) {
+            $lineitemssql = "SELECT l.*, t.vendorcode as vendorcode, t.guid as guid
+                               FROM {ltiservice_gradebookservices} l
+                         INNER JOIN {lti_tool_proxies} t ON (t.id = l.toolproxyid)
+                              WHERE l.courseid = ?
+                                AND l.toolproxyid = ?
+                                AND l.typeid is null";
+            $lineitemsparams = ['courseid' => backup::VAR_COURSEID, backup_helper::is_sqlparam($toolproxyid)];
+        } else {
+            $lineitemssql = "SELECT l.*, null as vendorcode, null as guid
+                               FROM {ltiservice_gradebookservices} l
+                              WHERE l.courseid = ?
+                                AND l.typeid = ?
+                                AND l.toolproxyid is null";
+            $lineitemsparams = ['courseid' => backup::VAR_COURSEID, backup_helper::is_sqlparam($typeid)];
+        }
+
+        $lineitem->set_source_sql($lineitemssql, $lineitemsparams);
+
+        return $subplugin;
+    }
+}
diff --git a/mod/lti/service/gradebookservices/backup/moodle2/restore_ltiservice_gradebookservices_subplugin.class.php b/mod/lti/service/gradebookservices/backup/moodle2/restore_ltiservice_gradebookservices_subplugin.class.php
new file mode 100644
index 0000000000000..35a16f6041598
--- /dev/null
+++ b/mod/lti/service/gradebookservices/backup/moodle2/restore_ltiservice_gradebookservices_subplugin.class.php
@@ -0,0 +1,209 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains the class for restore of this gradebookservices plugin
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->dirroot.'/mod/lti/locallib.php');
+
+/**
+ * Restore subplugin class.
+ *
+ * Provides the necessary information
+ * needed to restore the lineitems related with the lti activity (coupled),
+ * and all the uncoupled ones from the course.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class restore_ltiservice_gradebookservices_subplugin extends restore_subplugin {
+
+    /**
+     * Returns the subplugin structure to attach to the XML element.
+     *
+     * @return restore_path_element[] array of elements to be processed on restore.
+     */
+    protected function define_lti_subplugin_structure() {
+
+        $paths = array();
+        $elename = $this->get_namefor('lineitem');
+        $elepath = $this->get_pathfor('/lineitems/lineitem');
+        $paths[] = new restore_path_element($elename, $elepath);
+        return $paths;
+    }
+
+    /**
+     * Processes one lineitem
+     *
+     * @param mixed $data
+     * @return void
+     */
+    public function process_ltiservice_gradebookservices_lineitem($data) {
+        global $DB;
+        $data = (object)$data;
+        // The coupled lineitems are restored as any other grade item
+        // so we will only create the entry in the ltiservice_gradebookservices table.
+        // We will try to find a valid toolproxy in the system.
+        // If it has been found before... we use it.
+        /* cache parent property to account for missing PHPDoc type specification */
+        /** @var backup_activity_task $activitytask */
+        $activitytask = $this->task;
+        $courseid = $activitytask->get_courseid();
+        if ($data->typeid != null) {
+            if ($ltitypeid = $this->get_mappingid('ltitype', $data->typeid)) {
+                $newtypeid = $ltitypeid;
+            } else { // If not, then we will call our own function to find it.
+                $newtypeid = $this->find_typeid($data, $courseid);
+            }
+        } else {
+            $newtypeid = null;
+        }
+        if ($data->toolproxyid != null) {
+            $ltitoolproxy = $this->get_mappingid('ltitoolproxy', $data->toolproxyid);
+            if ($ltitoolproxy && $ltitoolproxy != 0) {
+                $newtoolproxyid = $ltitoolproxy;
+            } else { // If not, then we will call our own function to find it.
+                $newtoolproxyid = $this->find_proxy_id($data);
+            }
+        } else {
+            $newtoolproxyid = null;
+        }
+        if ($data->ltilinkid != null) {
+            $ltilinkid = $this->get_new_parentid('lti');
+        } else {
+            $ltilinkid = null;
+        }
+        // If this has not been restored before.
+        if ($this->get_mappingid('gbsgradeitemrestored',  $data->id, 0) == 0) {
+            $newgbsid = $DB->insert_record('ltiservice_gradebookservices', (object) array(
+                    'gradeitemid' => 0,
+                    'courseid' => $courseid,
+                    'toolproxyid' => $newtoolproxyid,
+                    'ltilinkid' => $ltilinkid,
+                    'typeid' => $newtypeid,
+                    'baseurl' => $data->baseurl,
+                    'tag' => $data->tag
+            ));
+            $this->set_mapping('gbsgradeitemoldid', $newgbsid, $data->gradeitemid);
+            $this->set_mapping('gbsgradeitemrestored', $data->id, $data->id);
+        }
+    }
+
+    /**
+     * If the toolproxy is not in the mapping (or it is 0)
+     * we try to find the toolproxyid.
+     * If none is found, then we set it to 0.
+     *
+     * @param mixed $data
+     * @return integer $newtoolproxyid
+     */
+    private function find_proxy_id($data) {
+        global $DB;
+        $newtoolproxyid = 0;
+        $oldtoolproxyguid = $data->guid;
+        $oldtoolproxyvendor = $data->vendorcode;
+
+        $dbtoolproxyjsonparams = array('guid' => $oldtoolproxyguid, 'vendorcode' => $oldtoolproxyvendor);
+        $dbtoolproxy = $DB->get_field('lti_tool_proxies', 'id', $dbtoolproxyjsonparams, IGNORE_MISSING);
+        if ($dbtoolproxy) {
+            $newtoolproxyid = $dbtoolproxy;
+        }
+        return $newtoolproxyid;
+    }
+
+    /**
+     * If the typeid is not in the mapping or it is 0, (it should be most of the times)
+     * we will try to find the better typeid that matches with the lineitem.
+     * If none is found, then we set it to 0.
+     *
+     * @param stdClass $data
+     * @param int $courseid
+     * @return int The item type id
+     */
+    private function find_typeid($data, $courseid) {
+        global $DB;
+        $newtypeid = 0;
+        $oldtypeid = $data->typeid;
+
+        // 1. Find a type with the same id in the same course.
+        $dbtypeidparameter = array('id' => $oldtypeid, 'course' => $courseid, 'baseurl' => $data->baseurl);
+        $dbtype = $DB->get_field_select('lti_types', 'id', "id=:id
+                AND course=:course AND ".$DB->sql_compare_text('baseurl')."=:baseurl",
+                $dbtypeidparameter);
+        if ($dbtype) {
+            $newtypeid = $dbtype;
+        } else {
+            // 2. Find a site type for all the courses (course == 1), but with the same id.
+            $dbtypeidparameter = array('id' => $oldtypeid, 'baseurl' => $data->baseurl);
+            $dbtype = $DB->get_field_select('lti_types', 'id', "id=:id
+                    AND course=1 AND ".$DB->sql_compare_text('baseurl')."=:baseurl",
+                    $dbtypeidparameter);
+            if ($dbtype) {
+                $newtypeid = $dbtype;
+            } else {
+                // 3. Find a type with the same baseurl in the actual site.
+                $dbtypeidparameter = array('course' => $courseid, 'baseurl' => $data->baseurl);
+                $dbtype = $DB->get_field_select('lti_types', 'id', "course=:course
+                        AND ".$DB->sql_compare_text('baseurl')."=:baseurl",
+                        $dbtypeidparameter);
+                if ($dbtype) {
+                    $newtypeid = $dbtype;
+                } else {
+                    // 4. Find a site type for all the courses (course == 1) with the same baseurl.
+                    $dbtypeidparameter = array('course' => 1, 'baseurl' => $data->baseurl);
+                    $dbtype = $DB->get_field_select('lti_types', 'id', "course=1
+                            AND ".$DB->sql_compare_text('baseurl')."=:baseurl",
+                            $dbtypeidparameter);
+                    if ($dbtype) {
+                        $newtypeid = $dbtype;
+                    }
+                }
+            }
+        }
+        return $newtypeid;
+    }
+
+    /**
+     * We call the after_restore_lti to update the grade_items id's that we didn't know in the moment of creating
+     * the gradebookservices rows.
+     */
+    protected function after_restore_lti() {
+        global $DB;
+        $activitytask = $this->task;
+        $courseid = $activitytask->get_courseid();
+        $gbstoupdate = $DB->get_records('ltiservice_gradebookservices', array('gradeitemid' => 0, 'courseid' => $courseid));
+        foreach ($gbstoupdate as $gbs) {
+            $oldgradeitemid = $this->get_mappingid('gbsgradeitemoldid', $gbs->id, 0);
+            $newgradeitemid = $this->get_mappingid('grade_item', $oldgradeitemid, 0);
+            if ($newgradeitemid > 0) {
+                $gbs->gradeitemid = $newgradeitemid;
+                $DB->update_record('ltiservice_gradebookservices', $gbs);
+            }
+        }
+    }
+
+}
diff --git a/mod/lti/service/gradebookservices/classes/local/resources/lineitem.php b/mod/lti/service/gradebookservices/classes/local/resources/lineitem.php
new file mode 100644
index 0000000000000..16a3620e74e18
--- /dev/null
+++ b/mod/lti/service/gradebookservices/classes/local/resources/lineitem.php
@@ -0,0 +1,365 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains a class definition for the LineItem resource
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace ltiservice_gradebookservices\local\resources;
+
+use ltiservice_gradebookservices\local\service\gradebookservices;
+use mod_lti\local\ltiservice\resource_base;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * A resource implementing LineItem.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class lineitem extends resource_base {
+
+    /**
+     * Class constructor.
+     *
+     * @param gradebookservices $service Service instance
+     */
+    public function __construct($service) {
+
+        parent::__construct($service);
+        $this->id = 'LineItem.item';
+        $this->template = '/{context_id}/lineitems/{item_id}/lineitem';
+        $this->variables[] = 'LineItem.url';
+        $this->formats[] = 'application/vnd.ims.lis.v2.lineitem+json';
+        $this->methods[] = self::HTTP_GET;
+        $this->methods[] = self::HTTP_PUT;
+        $this->methods[] = self::HTTP_DELETE;
+
+    }
+
+    /**
+     * Execute the request for this resource.
+     *
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
+     */
+    public function execute($response) {
+        global $CFG, $DB;
+
+        $params = $this->parse_template();
+        $contextid = $params['context_id'];
+        $itemid = $params['item_id'];
+        if ($response->get_request_method() === 'GET') {
+            $contenttype = $response->get_accept();
+        } else {
+            $contenttype = $response->get_content_type();
+        }
+        // We will receive typeid when working with LTI 1.x, if not then we are in LTI 2.
+        $typeid = optional_param('type_id', null, PARAM_ALPHANUM);
+        if (is_null($typeid)) {
+            if (!$this->check_tool_proxy(null, $response->get_request_data())) {
+                $response->set_code(403);
+                $response->set_reason("Invalid tool proxy specified.");
+                return;
+            }
+        } else {
+            switch ($response->get_request_method()) {
+                case self::HTTP_GET:
+                    if (!$this->check_type($typeid, $contextid, 'LineItem.item:get', $response->get_request_data())) {
+                        $response->set_code(403);
+                        $response->set_reason("This resource does not support GET requests.");
+                        return;
+                    }
+                    break;
+                case self::HTTP_PUT:
+                    if (!$this->check_type($typeid, $contextid, 'LineItem.item:put', $response->get_request_data())) {
+                        $response->set_code(403);
+                        $response->set_reason("This resource does not support PUT requests.");
+                        return;
+                    }
+                    break;
+                case self::HTTP_DELETE:
+                    if (!$this->check_type($typeid, $contextid, 'LineItem.item:delete', $response->get_request_data())) {
+                        $response->set_code(403);
+                        $response->set_reason("This resource does not support DELETE requests.");
+                        return;
+                    }
+                    break;
+                default:  // Should not be possible.
+                    $response->set_code(405);
+                    return;
+            }
+        }
+        if (empty($contextid) || (!empty($contenttype) && !in_array($contenttype, $this->formats))) {
+            $response->set_code(400);
+            $response->set_reason("Invalid request made.");
+            return;
+        }
+        if (!$DB->record_exists('course', array('id' => $contextid))) {
+            $response->set_code(404);
+            $response->set_reason("Not Found: Course $contextid doesn't exist.");
+            return;
+        }
+        if (!$DB->record_exists('grade_items', array('id' => $itemid))) {
+            $response->set_code(404);
+            $response->set_reason("Not Found: Grade item $itemid doesn't exist.");
+            return;
+        }
+        $item = $this->get_service()->get_lineitem($contextid, $itemid, $typeid);
+        if ($item === false) {
+            $response->set_code(403);
+            $response->set_reason("Line item does not exist.");
+            return;
+        }
+        require_once($CFG->libdir.'/gradelib.php');
+        switch ($response->get_request_method()) {
+            case 'GET':
+                $this->get_request($response, $item, $typeid);
+                break;
+            case 'PUT':
+                $json = $this->process_put_request($response->get_request_data(), $item, $typeid);
+                $response->set_body($json);
+                $response->set_code(200);
+                break;
+            case 'DELETE':
+                $this->process_delete_request($item);
+                $response->set_code(204);
+                break;
+            default:  // Should not be possible.
+                $response->set_code(405);
+                $response->set_reason("Invalid request method specified.");
+                return;
+        }
+    }
+
+    /**
+     * Process a GET request.
+     *
+     * @param \mod_lti\local\ltiservice\response $response Response object for this request.
+     * @param object $item Grade item instance.
+     * @param string $typeid Tool Type Id
+     */
+    private function get_request($response, $item, $typeid) {
+
+        $response->set_content_type($this->formats[0]);
+        $lineitem = gradebookservices::item_for_json($item, substr(parent::get_endpoint(),
+                0, strrpos(parent::get_endpoint(), "/", -10)), $typeid);
+        $response->set_body(json_encode($lineitem));
+
+    }
+
+    /**
+     * Process a PUT request.
+     *
+     * @param string $body PUT body
+     * @param \ltiservice_gradebookservices\local\resources\lineitem $olditem Grade item instance
+     * @param string $typeid Tool Type Id
+     *
+     * @return string
+     * @throws \Exception
+     */
+    private function process_put_request($body, $olditem, $typeid) {
+        global $DB;
+        $json = json_decode($body);
+        if (empty($json) ||
+                !isset($json->scoreMaximum) ||
+                !isset($json->label)) {
+            throw new \Exception(null, 400);
+        }
+        $item = \grade_item::fetch(array('id' => $olditem->id, 'courseid' => $olditem->courseid));
+        $gbs = gradebookservices::find_ltiservice_gradebookservice_for_lineitem($olditem->id);
+        $updategradeitem = false;
+        $rescalegrades = false;
+        $oldgrademax = grade_floatval($item->grademax);
+        $upgradegradebookservices = false;
+        if ($item->itemname !== $json->label) {
+            $updategradeitem = true;
+        }
+        $item->itemname = $json->label;
+        if (!is_numeric($json->scoreMaximum)) {
+            throw new \Exception(null, 400);
+        } else {
+            if (grade_floats_different($oldgrademax,
+                    grade_floatval($json->scoreMaximum))) {
+                $updategradeitem = true;
+                $rescalegrades = true;
+            }
+            $item->grademax = grade_floatval($json->scoreMaximum);
+        }
+        $resourceid = (isset($json->resourceId)) ? $json->resourceId : '';
+        if ($item->idnumber !== $resourceid) {
+            $updategradeitem = true;
+        }
+        $item->idnumber = $resourceid;
+        if ($gbs) {
+            $tag = (isset($json->tag)) ? $json->tag : null;
+            if ($gbs->tag !== $tag) {
+                $upgradegradebookservices = true;
+            }
+            $gbs->tag = $tag;
+        }
+        $ltilinkid = null;
+        if (isset($json->ltiLinkId)) {
+            if (is_numeric($json->ltiLinkId)) {
+                $ltilinkid = $json->ltiLinkId;
+                if ($gbs) {
+                    if (intval($gbs->ltilinkid) !== intval($json->ltiLinkId)) {
+                        $gbs->ltilinkid = $json->ltiLinkId;
+                        $upgradegradebookservices = true;
+                    }
+                } else {
+                    if (intval($item->iteminstance) !== intval($json->ltiLinkId)) {
+                        $item->iteminstance = intval($json->ltiLinkId);
+                        $updategradeitem = true;
+                    }
+                }
+            } else {
+                throw new \Exception(null, 400);
+            }
+        }
+        if ($ltilinkid != null) {
+            if (is_null($typeid)) {
+                if (!gradebookservices::check_lti_id($ltilinkid, $item->courseid,
+                        $this->get_service()->get_tool_proxy()->id)) {
+                            throw new \Exception(null, 403);
+                }
+            } else {
+                if (!gradebookservices::check_lti_1x_id($ltilinkid, $item->courseid,
+                        $typeid)) {
+                            throw new \Exception(null, 403);
+                }
+            }
+        }
+        if ($updategradeitem) {
+            if (!$item->update('mod/ltiservice_gradebookservices')) {
+                throw new \Exception(null, 500);
+            }
+            if ($rescalegrades) {
+                $item->rescale_grades_keep_percentage(0, $oldgrademax, 0, $item->grademax);
+            }
+        }
+
+        $lineitem = new lineitem($this->get_service());
+        $endpoint = $lineitem->get_endpoint();
+
+        if ($upgradegradebookservices) {
+            if (is_null($typeid)) {
+                $toolproxyid = $this->get_service()->get_tool_proxy()->id;
+                $baseurl = null;
+            } else {
+                $toolproxyid = null;
+                $baseurl = lti_get_type_type_config($typeid)->lti_toolurl;
+            }
+            $DB->update_record('ltiservice_gradebookservices', (object)array(
+                    'id' => $gbs->id,
+                    'gradeitemid' => $gbs->gradeitemid,
+                    'courseid' => $gbs->courseid,
+                    'toolproxyid' => $toolproxyid,
+                    'typeid' => $typeid,
+                    'baseurl' => $baseurl,
+                    'ltilinkid' => $ltilinkid,
+                    'tag' => $gbs->tag
+            ));
+        }
+
+        if (is_null($typeid)) {
+            $id = "{$endpoint}";
+            $json->id = $id;
+        } else {
+            $id = "{$endpoint}?type_id={$typeid}";
+            $json->id = $id;
+        }
+        return json_encode($json, JSON_UNESCAPED_SLASHES);
+
+    }
+
+    /**
+     * Process a DELETE request.
+     *
+     * @param \ltiservice_gradebookservices\local\resources\lineitem $item Grade item instance
+     * @throws \Exception
+     */
+    private function process_delete_request($item) {
+        global $DB;
+
+        $gradeitem = \grade_item::fetch(array('id' => $item->id));
+        if (($gbs = gradebookservices::find_ltiservice_gradebookservice_for_lineitem($item->id)) == false) {
+            throw new \Exception(null, 403);
+        }
+        if (!$gradeitem->delete('mod/ltiservice_gradebookservices')) {
+            throw new \Exception(null, 500);
+        } else {
+            $sqlparams = array();
+            $sqlparams['id'] = $gbs->id;
+            if (!$DB->delete_records('ltiservice_gradebookservices', $sqlparams)) {
+                throw new \Exception(null, 500);
+            }
+        }
+    }
+
+    /**
+     * Get permissions from the config of the tool for that resource
+     *
+     * @param int $typeid
+     *
+     * @return array with the permissions related to this resource by the $lti_type or null if none.
+     */
+    public function get_permissions($typeid) {
+        $tool = lti_get_type_type_config($typeid);
+        if ($tool->ltiservice_gradesynchronization == '1') {
+            return array('LineItem.item:get');
+        } else if ($tool->ltiservice_gradesynchronization == '2') {
+            return array('LineItem.item:get', 'LineItem.item:put', 'LineItem.item:delete');
+        } else {
+            return array();
+        }
+    }
+
+    /**
+     * Parse a value for custom parameter substitution variables.
+     *
+     * @param string $value String to be parsed
+     *
+     * @return string
+     */
+    public function parse_value($value) {
+        global $COURSE, $CFG;
+        if (strpos($value, '$LineItem.url') !== false) {
+            $resolved = '';
+            require_once($CFG->libdir . '/gradelib.php');
+
+            $this->params['context_id'] = $COURSE->id;
+            $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
+            if (!empty($id)) {
+                $cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);
+                $id = $cm->instance;
+                $item = grade_get_grades($COURSE->id, 'mod', 'lti', $id);
+                if ($item && $item->items) {
+                    $this->params['item_id'] = $item->items[0]->id;
+                    $resolved = parent::get_endpoint();
+                }
+            }
+            $value = str_replace('$LineItem.url', $resolved, $value);
+        }
+        return $value;
+    }
+}
diff --git a/mod/lti/service/gradebookservices/classes/local/resources/lineitems.php b/mod/lti/service/gradebookservices/classes/local/resources/lineitems.php
new file mode 100644
index 0000000000000..cd70180adefdc
--- /dev/null
+++ b/mod/lti/service/gradebookservices/classes/local/resources/lineitems.php
@@ -0,0 +1,352 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains a class definition for the LineItem container resource
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace ltiservice_gradebookservices\local\resources;
+
+use ltiservice_gradebookservices\local\service\gradebookservices;
+use mod_lti\local\ltiservice\resource_base;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * A resource implementing LineItem container.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class lineitems extends resource_base {
+
+    /**
+     * Class constructor.
+     *
+     * @param \ltiservice_gradebookservices\local\service\gradebookservices $service Service instance
+     */
+    public function __construct($service) {
+
+        parent::__construct($service);
+        $this->id = 'LineItem.collection';
+        $this->template = '/{context_id}/lineitems';
+        $this->variables[] = 'LineItems.url';
+        $this->formats[] = 'application/vnd.ims.lis.v2.lineitemcontainer+json';
+        $this->formats[] = 'application/vnd.ims.lis.v2.lineitem+json';
+        $this->methods[] = self::HTTP_GET;
+        $this->methods[] = self::HTTP_POST;
+
+    }
+
+    /**
+     * Execute the request for this resource.
+     *
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
+     */
+    public function execute($response) {
+        global $DB;
+
+        $params = $this->parse_template();
+        $contextid = $params['context_id'];
+        $isget = $response->get_request_method() === self::HTTP_GET;
+        if ($isget) {
+            $contenttype = $response->get_accept();
+        } else {
+            $contenttype = $response->get_content_type();
+        }
+        $container = empty($contenttype) || ($contenttype === $this->formats[0]);
+        // We will receive typeid when working with LTI 1.x, if not the we are in LTI 2.
+        $typeid = optional_param('type_id', null, PARAM_ALPHANUM);
+        if (is_null($typeid)) {
+            if (!$this->check_tool_proxy(null, $response->get_request_data())) {
+                $response->set_code(403);
+                $response->set_reason("Invalid tool proxy specified.");
+                return;
+            }
+        } else {
+            switch ($response->get_request_method()) {
+                case self::HTTP_GET:
+                    if (!$this->check_type($typeid, $contextid, 'LineItem.collection:get', $response->get_request_data())) {
+                        $response->set_code(403);
+                        $response->set_reason("This resource does not support GET requests.");
+                        return;
+                    }
+                    break;
+                case self::HTTP_POST:
+                    if (!$this->check_type($typeid, $contextid, 'LineItem.collection:post', $response->get_request_data())) {
+                        $response->set_code(403);
+                        $response->set_reason("This resource does not support POST requests.");
+                        return;
+                    }
+                    break;
+                default:  // Should not be possible.
+                    $response->set_code(405);
+                    $response->set_reason("Invalid request method specified.");
+                    return;
+            }
+        }
+        if (empty($contextid) || !($container ^ ($response->get_request_method() === self::HTTP_POST)) ||
+                (!empty($contenttype) && !in_array($contenttype, $this->formats))) {
+            $response->set_code(400);
+            $response->set_reason("Invalid request made.");
+            return;
+        }
+        if (!$DB->record_exists('course', array('id' => $contextid))) {
+            $response->set_code(404);
+            $response->set_reason("Not Found: Course $contextid doesn't exist.");
+            return;
+        }
+        switch ($response->get_request_method()) {
+            case self::HTTP_GET:
+                $resourceid = optional_param('resource_id', null, PARAM_TEXT);
+                $ltilinkid = optional_param('lti_link_id', null, PARAM_TEXT);
+                $tag = optional_param('tag', null, PARAM_TEXT);
+                $limitnum = optional_param('limit', 0, PARAM_INT);
+                $limitfrom = optional_param('from', 0, PARAM_INT);
+                $itemsandcount = $this->get_service()->get_lineitems($contextid, $resourceid, $ltilinkid, $tag, $limitfrom,
+                        $limitnum, $typeid);
+                $items = $itemsandcount[1];
+                $totalcount = $itemsandcount[0];
+                $json = $this->get_json_for_get_request($items, $resourceid, $ltilinkid, $tag, $limitfrom,
+                        $limitnum, $totalcount, $typeid, $response);
+                $response->set_content_type($this->formats[0]);
+                break;
+            case self::HTTP_POST:
+                try {
+                    $json = $this->get_json_for_post_request($response->get_request_data(), $contextid, $typeid);
+                    $response->set_code(201);
+                    $response->set_content_type($this->formats[1]);
+                } catch (\Exception $e) {
+                    $response->set_code($e->getCode());
+                    $response->set_reason($e->getMessage());
+                }
+                break;
+            default:  // Should not be possible.
+                $response->set_code(405);
+                $response->set_reason("Invalid request method specified.");
+                return;
+        }
+        $response->set_body($json);
+    }
+
+    /**
+     * Generate the JSON for a GET request.
+     *
+     * @param array $items Array of lineitems
+     * @param string $resourceid Resource identifier used for filtering, may be null
+     * @param string $ltilinkid Resource Link identifier used for filtering, may be null
+     * @param string $tag Tag identifier used for filtering, may be null
+     * @param int $limitfrom Offset of the first line item to return
+     * @param int $limitnum Maximum number of line items to return, ignored if zero or less
+     * @param int $totalcount Number of total lineitems before filtering for paging
+     * @param int $typeid Maximum number of line items to return, ignored if zero or less
+     * @param \mod_lti\local\ltiservice\response $response
+
+     * @return string
+     */
+    private function get_json_for_get_request($items, $resourceid, $ltilinkid,
+            $tag, $limitfrom, $limitnum, $totalcount, $typeid, $response) {
+
+        $firstpage = null;
+        $nextpage = null;
+        $prevpage = null;
+        $lastpage = null;
+        if (isset($limitnum) && $limitnum > 0) {
+            if ($limitfrom >= $totalcount || $limitfrom < 0) {
+                $outofrange = true;
+            } else {
+                $outofrange = false;
+            }
+            $limitprev = $limitfrom - $limitnum >= 0 ? $limitfrom - $limitnum : 0;
+            $limitcurrent = $limitfrom;
+            $limitlast = $totalcount - $limitnum + 1 >= 0 ? $totalcount - $limitnum + 1 : 0;
+            $limitfrom += $limitnum;
+
+            $baseurl = new \moodle_url($this->get_endpoint());
+            if (isset($resourceid)) {
+                $baseurl->param('resource_id', $resourceid);
+            }
+            if (isset($ltilinkid)) {
+                $baseurl->param('lti_link_id', $ltilinkid);
+            }
+            if (isset($tag)) {
+                $baseurl->param('tag', $tag);
+            }
+
+            if (is_null($typeid)) {
+                $baseurl->param('limit', $limitnum);
+                if (($limitfrom <= $totalcount - 1) && (!$outofrange)) {
+                    $nextpage = new \moodle_url($baseurl, ['from' => $limitfrom]);
+                }
+                $firstpage = new \moodle_url($baseurl, ['from' => 0]);
+                $canonicalpage = new \moodle_url($baseurl, ['from' => $limitcurrent]);
+                $lastpage = new \moodle_url($baseurl, ['from' > $limitlast]);
+                if (($limitcurrent > 0) && (!$outofrange)) {
+                    $prevpage = new \moodle_url($baseurl, ['from' => $limitprev]);
+                }
+            } else {
+                $baseurl->params(['type_id' => $typeid, 'limit' => $limitnum]);
+                if (($limitfrom <= $totalcount - 1) && (!$outofrange)) {
+                    $nextpage = new \moodle_url($baseurl, ['from' => $limitfrom]);
+                }
+                $firstpage = new \moodle_url($baseurl, ['from' => 0]);
+                $canonicalpage = new \moodle_url($baseurl, ['from' => $limitcurrent]);
+                $lastpage = new \moodle_url($baseurl, ['from' => $limitlast]);
+                if (($limitcurrent > 0) && (!$outofrange)) {
+                    $prevpage = new \moodle_url($baseurl, ['from' => $limitprev]);
+                }
+            }
+        }
+
+        $jsonitems=[];
+        $endpoint = parent::get_endpoint();
+        foreach ($items as $item) {
+            array_push($jsonitems, gradebookservices::item_for_json($item, $endpoint, $typeid));
+        }
+
+        if (isset($canonicalpage) && ($canonicalpage)) {
+            $links = 'Link: <' . $firstpage->out() . '>; rel=“first”';
+            if (!is_null($prevpage)) {
+                $links .= ', <' . $prevpage->out() . '>; rel=“prev”';
+            }
+            $links .= ', <' . $canonicalpage->out(). '>; rel=“canonical”';
+            if (!is_null($nextpage)) {
+                $links .= ', <' . $nextpage->out() . '>; rel=“next”';
+            }
+            $links .= ', <' . $lastpage->out() . '>; rel=“last”';
+            $response->add_additional_header($links);
+        }
+        return json_encode($jsonitems);
+    }
+
+    /**
+     * Generate the JSON for a POST request.
+     *
+     * @param string $body POST body
+     * @param string $contextid Course ID
+     * @param string $typeid
+     *
+     * @return string
+     * @throws \Exception
+     */
+    private function get_json_for_post_request($body, $contextid, $typeid) {
+        global $CFG, $DB;
+
+        $json = json_decode($body);
+        if (empty($json) ||
+                !isset($json->scoreMaximum) ||
+                !isset($json->label)) {
+            throw new \Exception(null, 400);
+        }
+        if (is_numeric($json->scoreMaximum)) {
+            $max = $json->scoreMaximum;
+        } else {
+            throw new \Exception(null, 400);
+        }
+        require_once($CFG->libdir.'/gradelib.php');
+        $resourceid = (isset($json->resourceId)) ? $json->resourceId : '';
+        $ltilinkid = (isset($json->ltiLinkId)) ? $json->ltiLinkId : null;
+        if ($ltilinkid != null) {
+            if (is_null($typeid)) {
+                if (!gradebookservices::check_lti_id($ltilinkid, $contextid, $this->get_service()->get_tool_proxy()->id)) {
+                    throw new \Exception(null, 403);
+                }
+            } else {
+                if (!gradebookservices::check_lti_1x_id($ltilinkid, $contextid, $typeid)) {
+                    throw new \Exception(null, 403);
+                }
+            }
+        }
+        $tag = (isset($json->tag)) ? $json->tag : '';
+        if (is_null($typeid)) {
+            $toolproxyid = $this->get_service()->get_tool_proxy()->id;
+            $baseurl = null;
+        } else {
+            $toolproxyid = null;
+            $baseurl = lti_get_type_type_config($typeid)->lti_toolurl;
+        }
+        $params = array();
+        $params['itemname'] = $json->label;
+        $params['gradetype'] = GRADE_TYPE_VALUE;
+        $params['grademax']  = $max;
+        $params['grademin']  = 0;
+        $item = new \grade_item(array('id' => 0, 'courseid' => $contextid));
+        \grade_item::set_properties($item, $params);
+        $item->itemtype = 'manual';
+        $item->idnumber = $resourceid;
+        $item->grademax = $max;
+        $id = $item->insert('mod/ltiservice_gradebookservices');
+        $DB->insert_record('ltiservice_gradebookservices', (object)array(
+                'gradeitemid' => $id,
+                'courseid' => $contextid,
+                'toolproxyid' => $toolproxyid,
+                'typeid' => $typeid,
+                'baseurl' => $baseurl,
+                'ltilinkid' => $ltilinkid,
+                'tag' => $tag
+        ));
+        if (is_null($typeid)) {
+            $json->id = parent::get_endpoint() . "/{$id}/lineitem";
+        } else {
+            $json->id = parent::get_endpoint() . "/{$id}/lineitem?type_id={$typeid}";
+        }
+        return json_encode($json, JSON_UNESCAPED_SLASHES);
+
+    }
+
+    /**
+     * get permissions from the config of the tool for that resource
+     *
+     * @param string $typeid
+     *
+     * @return array with the permissions related to this resource by the lti type or null if none.
+     */
+    public function get_permissions($typeid) {
+        $tool = lti_get_type_type_config($typeid);
+        if ($tool->ltiservice_gradesynchronization == '1') {
+            return array('LineItem.collection:get');
+        } else if ($tool->ltiservice_gradesynchronization == '2') {
+            return array('LineItem.collection:get', 'LineItem.collection:post');
+        } else {
+            return array();
+        }
+    }
+
+    /**
+     * Parse a value for custom parameter substitution variables.
+     *
+     * @param string $value String to be parsed
+     *
+     * @return string
+     */
+    public function parse_value($value) {
+        global $COURSE;
+
+        if (strpos($value, '$LineItems.url') !== false) {
+            $this->params['context_id'] = $COURSE->id;
+            $value = str_replace('$LineItems.url', parent::get_endpoint(), $value);
+        }
+
+        return $value;
+
+    }
+}
diff --git a/mod/lti/service/gradebookservices/classes/local/resources/results.php b/mod/lti/service/gradebookservices/classes/local/resources/results.php
new file mode 100644
index 0000000000000..445c1dc91f49a
--- /dev/null
+++ b/mod/lti/service/gradebookservices/classes/local/resources/results.php
@@ -0,0 +1,304 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains a class definition for the LISResults container resource
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace ltiservice_gradebookservices\local\resources;
+
+use ltiservice_gradebookservices\local\service\gradebookservices;
+use mod_lti\local\ltiservice\resource_base;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * A resource implementing LISResults container.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class results extends resource_base {
+
+    /**
+     * Class constructor.
+     *
+     * @param \ltiservice_gradebookservices\local\service\gradebookservices $service Service instance
+     */
+    public function __construct($service) {
+
+        parent::__construct($service);
+        $this->id = 'Result.collection';
+        $this->template = '/{context_id}/lineitems/{item_id}/lineitem/results';
+        $this->variables[] = 'Results.url';
+        $this->formats[] = 'application/vnd.ims.lis.v2.resultcontainer+json';
+        $this->methods[] = 'GET';
+    }
+
+    /**
+     * Execute the request for this resource.
+     *
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
+     */
+    public function execute($response) {
+        global $CFG, $DB;
+
+        $params = $this->parse_template();
+        $contextid = $params['context_id'];
+        $itemid = $params['item_id'];
+
+        $isget = $response->get_request_method() === 'GET';
+        if ($isget) {
+            $contenttype = $response->get_accept();
+        } else {
+            $contenttype = $response->get_content_type();
+        }
+        // We will receive typeid when working with LTI 1.x, if not the we are in LTI 2.
+        $typeid = optional_param('type_id', null, PARAM_ALPHANUM);
+        if (is_null($typeid)) {
+            if (!$this->check_tool_proxy(null, $response->get_request_data())) {
+                $response->set_code(403);
+                $response->set_reason("Invalid tool proxy specified.");
+                return;
+            }
+        } else {
+            if (!$this->check_type($typeid, $contextid, 'Result.collection:get', $response->get_request_data())) {
+                $response->set_code(403);
+                $response->set_reason("This resource does not support GET requests.");
+                return;
+            }
+        }
+        if (empty($contextid) || (!empty($contenttype) && !in_array($contenttype, $this->formats))) {
+            $response->set_code(400);
+            $response->set_reason("Invalid request made.");
+            return;
+        }
+        if (!$DB->record_exists('course', array('id' => $contextid))) {
+            $response->set_code(404);
+            $response->set_reason("Not Found: Course $contextid doesn't exist.");
+            return;
+        }
+        if (!$DB->record_exists('grade_items', array('id' => $itemid))) {
+            $response->set_code(404);
+            $response->set_reason("Not Found: Grade item $itemid doesn't exist.");
+            return;
+        }
+        $item = $this->get_service()->get_lineitem($contextid, $itemid, $typeid);
+        if ($item === false) {
+            $response->set_code(403);
+            $response->set_reason("Line item does not exist.");
+            return;
+        }
+        $gbs = gradebookservices::find_ltiservice_gradebookservice_for_lineitem($itemid);
+        $ltilinkid = null;
+        if (isset($item->iteminstance)) {
+            $ltilinkid = $item->iteminstance;
+        } else if ($gbs && isset($gbs->ltilinkid)) {
+            $ltilinkid = $gbs->ltilinkid;
+        }
+        if ($ltilinkid != null) {
+            if (is_null($typeid)) {
+                if (isset($item->iteminstance) && (!gradebookservices::check_lti_id($ltilinkid, $item->courseid,
+                        $this->get_service()->get_tool_proxy()->id))) {
+                    $response->set_code(403);
+                    $response->set_reason("Invalid LTI id supplied.");
+                    return;
+                }
+            } else {
+                if (isset($item->iteminstance) && (!gradebookservices::check_lti_1x_id($ltilinkid, $item->courseid,
+                        $typeid))) {
+                    $response->set_code(403);
+                    $response->set_reason("Invalid LTI id supplied.");
+                    return;
+                }
+            }
+        }
+        require_once($CFG->libdir.'/gradelib.php');
+        switch ($response->get_request_method()) {
+            case 'GET':
+                $useridfilter = optional_param('user_id', 0, PARAM_INT);
+                $limitnum = optional_param('limit', 0, PARAM_INT);
+                $limitfrom = optional_param('from', 0, PARAM_INT);
+                $typeid = optional_param('type_id', null, PARAM_TEXT);
+                $json = $this->get_json_for_get_request($item->id, $limitfrom, $limitnum,
+                        $useridfilter, $typeid, $response);
+                $response->set_content_type($this->formats[0]);
+                $response->set_body($json);
+                break;
+            default:  // Should not be possible.
+                $response->set_code(405);
+                $response->set_reason("Invalid request method specified.");
+                return;
+        }
+        $response->set_body($json);
+    }
+
+    /**
+     * Generate the JSON for a GET request.
+     *
+     * @param int    $itemid     Grade item instance ID
+     * @param int $limitfrom  Offset for the first result to include in this paged set
+     * @param int $limitnum   Maximum number of results to include in the response, ignored if zero
+     * @param int    $useridfilter     The user id to filter the results.
+     * @param int    $typeid     Lti tool typeid (or null)
+     * @param \mod_lti\local\ltiservice\response $response   The response element needed to add a header.
+     *
+     * @return string
+     */
+    private function get_json_for_get_request($itemid, $limitfrom, $limitnum, $useridfilter, $typeid, $response) {
+
+        if ($useridfilter > 0) {
+            $grades = \grade_grade::fetch_all(array('itemid' => $itemid, 'userid' => $useridfilter));
+        } else {
+            $grades = \grade_grade::fetch_all(array('itemid' => $itemid));
+        }
+
+        $firstpage = null;
+        $nextpage = null;
+        $prevpage = null;
+        $lastpage = null;
+        if ($grades && isset($limitnum) && $limitnum > 0) {
+            // Since we only display grades that have been modified, we need to filter first in order to support
+            // paging.
+            $resultgrades = array_filter($grades, function ($grade) {
+                return !empty($grade->timemodified);
+            });
+            // We save the total count to calculate the last page.
+            $totalcount = count($resultgrades);
+            // We slice to the requested item offset to insure proper item is always first, and we always return
+            // first pageset of any remaining items.
+            $grades = array_slice($resultgrades, $limitfrom);
+            if (count($grades) > 0) {
+                $pagedgrades = array_chunk($grades, $limitnum);
+                $pageset = 0;
+                $grades = $pagedgrades[$pageset];
+            }
+            if ($limitfrom >= $totalcount || $limitfrom < 0) {
+                $outofrange = true;
+            } else {
+                $outofrange = false;
+            }
+            $limitprev = $limitfrom - $limitnum >= 0 ? $limitfrom - $limitnum : 0;
+            $limitcurrent = $limitfrom;
+            $limitlast = $totalcount - $limitnum + 1 >= 0 ? $totalcount - $limitnum + 1 : 0;
+            $limitfrom += $limitnum;
+
+            $baseurl = new \moodle_url($this->get_endpoint());
+            if (is_null($typeid)) {
+                $baseurl->param('limit', $limitnum);
+
+                if (($limitfrom <= $totalcount - 1) && (!$outofrange)) {
+                    $nextpage = new \moodle_url($baseurl, ['from' => $limitfrom]);
+                }
+                $firstpage = new \moodle_url($baseurl, ['from' => 0]);
+                $canonicalpage = new \moodle_url($baseurl, ['from' => $limitcurrent]);
+                $lastpage = new \moodle_url($baseurl, ['from' => $limitlast]);
+                if (($limitcurrent > 0) && (!$outofrange)) {
+                    $prevpage = new \moodle_url($baseurl, ['from' => $limitprev]);
+                }
+            } else {
+                $baseurl->params(['type_id' => $typeid, 'limit' => $limitnum]);
+
+                if (($limitfrom <= $totalcount - 1) && (!$outofrange)) {
+                    $nextpage = new \moodle_url($baseurl, ['from' => $limitfrom]);
+                }
+                $firstpage = new \moodle_url($baseurl, ['from' => 0]);
+                $canonicalpage = new \moodle_url($baseurl, ['from' => $limitcurrent]);
+                if (($limitcurrent > 0) && (!$outofrange)) {
+                    $prevpage = new \moodle_url($baseurl, ['from' => $limitprev]);
+                }
+            }
+        }
+
+        $jsonresults = [];
+        $lineitem = new lineitem($this->get_service());
+        $endpoint = $lineitem->get_endpoint();
+        if ($grades) {
+            foreach ($grades as $grade) {
+                if (!empty($grade->timemodified)) {
+                    array_push($jsonresults, gradebookservices::result_for_json($grade, $endpoint, $typeid));
+                }
+            }
+        }
+
+        if (isset($canonicalpage) && ($canonicalpage)) {
+            $links = 'Link: <' . $firstpage->out() . '>; rel=“first”';
+            if (!is_null($prevpage)) {
+                $links .= ', <' . $prevpage->out() . '>; rel=“prev”';
+            }
+            $links .= ', <' . $canonicalpage->out() . '>; rel=“canonical”';
+            if (!is_null($nextpage)) {
+                $links .= ', <' . $nextpage->out() . '>; rel=“next”';
+            }
+            $links .= ', <' . $lastpage->out() . '>; rel=“last”';
+            $response->add_additional_header($links);
+        }
+        return json_encode($jsonresults);
+    }
+
+    /**
+     * get permissions from the config of the tool for that resource
+     *
+     * @param int $typeid
+     *
+     * @return array with the permissions related to this resource by the $lti_type or null if none.
+     */
+    public function get_permissions($typeid) {
+        $tool = lti_get_type_type_config($typeid);
+        if ($tool->ltiservice_gradesynchronization == '1') {
+            return array('Result.collection:get');
+        } else if ($tool->ltiservice_gradesynchronization == '2') {
+            return array('Result.collection:get');
+        } else {
+            return array();
+        }
+    }
+
+    /**
+     * Parse a value for custom parameter substitution variables.
+     *
+     * @param string $value String to be parsed
+     *
+     * @return string
+     */
+    public function parse_value($value) {
+        global $COURSE, $CFG;
+        if (strpos($value, '$Results.url') !== false) {
+            require_once($CFG->libdir . '/gradelib.php');
+
+            $resolved = '';
+            $this->params['context_id'] = $COURSE->id;
+            $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
+            if (!empty($id)) {
+                $cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);
+                $id = $cm->instance;
+                $item = grade_get_grades($COURSE->id, 'mod', 'lti', $id);
+                if ($item && $item->items) {
+                    $this->params['item_id'] = $item->items[0]->id;
+                    $resolved = parent::get_endpoint();
+                }
+            }
+            $value = str_replace('$Results.url', $resolved, $value);
+        }
+        return $value;
+    }
+}
diff --git a/mod/lti/service/gradebookservices/classes/local/resources/scores.php b/mod/lti/service/gradebookservices/classes/local/resources/scores.php
new file mode 100644
index 0000000000000..afe63eae98940
--- /dev/null
+++ b/mod/lti/service/gradebookservices/classes/local/resources/scores.php
@@ -0,0 +1,270 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains a class definition for the LISResult container resource
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace ltiservice_gradebookservices\local\resources;
+
+use ltiservice_gradebookservices\local\service\gradebookservices;
+use mod_lti\local\ltiservice\resource_base;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * A resource implementing LISResult container.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class scores extends resource_base {
+
+    /**
+     * Class constructor.
+     *
+     * @param \ltiservice_gradebookservices\local\service\gradebookservices $service Service instance
+     */
+    public function __construct($service) {
+
+        parent::__construct($service);
+        $this->id = 'Score.collection';
+        $this->template = '/{context_id}/lineitems/{item_id}/lineitem/scores';
+        $this->variables[] = 'Scores.url';
+        $this->formats[] = 'application/vnd.ims.lis.v1.scorecontainer+json';
+        $this->formats[] = 'application/vnd.ims.lis.v1.score+json';
+        $this->methods[] = 'POST';
+
+    }
+
+    /**
+     * Execute the request for this resource.
+     *
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
+     */
+    public function execute($response) {
+        global $CFG, $DB;
+
+        $params = $this->parse_template();
+        $contextid = $params['context_id'];
+        $itemid = $params['item_id'];
+
+        // GET is disabled by the moment, but we have the code ready
+        // for a future implementation.
+
+        $isget = $response->get_request_method() === 'GET';
+        if ($isget) {
+            $contenttype = $response->get_accept();
+        } else {
+            $contenttype = $response->get_content_type();
+        }
+        $container = empty($contenttype) || ($contenttype === $this->formats[0]);
+        // We will receive typeid when working with LTI 1.x, if not the we are in LTI 2.
+        $typeid = optional_param('type_id', null, PARAM_ALPHANUM);
+        if (is_null($typeid)) {
+            if (!$this->check_tool_proxy(null, $response->get_request_data())) {
+                $response->set_code(403);
+                return;
+            }
+        } else {
+            switch ($response->get_request_method()) {
+                case 'GET':
+                    $response->set_code(405);
+                    $response->set_reason("GET requests are not allowed.");
+                    return;
+                case 'POST':
+                    if (!$this->check_type($typeid, $contextid, 'Score.collection:post', $response->get_request_data())) {
+                        $response->set_code(401);
+                        $response->set_reason("This resource does not support POST requests.");
+                        return;
+                    }
+                    break;
+                default:  // Should not be possible.
+                    $response->set_code(405);
+                    return;
+            }
+        }
+        if (empty($contextid) || !($container ^ ($response->get_request_method() === 'POST')) ||
+                (!empty($contenttype) && !in_array($contenttype, $this->formats))) {
+            $response->set_code(400);
+            return;
+        }
+        if (!$DB->record_exists('course', array('id' => $contextid))) {
+            $response->set_code(404);
+            $response->set_reason("Not Found: Course $contextid doesn't exist.");
+            return;
+        }
+        if (!$DB->record_exists('grade_items', array('id' => $itemid))) {
+            $response->set_code(404);
+            $response->set_reason("Not Found: Grade item $itemid doesn't exist.");
+            return;
+        }
+        $item = $this->get_service()->get_lineitem($contextid, $itemid, $typeid);
+        if ($item === false) {
+            $response->set_code(403);
+            $response->set_reason("Line item does not exist.");
+            return;
+        }
+        $gbs = gradebookservices::find_ltiservice_gradebookservice_for_lineitem($itemid);
+        $ltilinkid = null;
+        if (isset($item->iteminstance)) {
+            $ltilinkid = $item->iteminstance;
+        } else if ($gbs && isset($gbs->ltilinkid)) {
+            $ltilinkid = $gbs->ltilinkid;
+        }
+        if ($ltilinkid != null) {
+            if (is_null($typeid)) {
+                if (isset($item->iteminstance) && (!gradebookservices::check_lti_id($ltilinkid, $item->courseid,
+                        $this->get_service()->get_tool_proxy()->id))) {
+                    $response->set_code(403);
+                    $response->set_reason("Invalid LTI id supplied.");
+                    return;
+                }
+            } else {
+                if (isset($item->iteminstance) && (!gradebookservices::check_lti_1x_id($ltilinkid, $item->courseid,
+                        $typeid))) {
+                    $response->set_code(403);
+                    $response->set_reason("Invalid LTI id supplied.");
+                    return;
+                }
+            }
+        }
+        $json = '[]';
+        require_once($CFG->libdir.'/gradelib.php');
+        switch ($response->get_request_method()) {
+            case 'GET':
+                $response->set_code(405);
+                $response->set_reason("GET requests are not allowed.");
+                break;
+            case 'POST':
+                try {
+                    $json = $this->get_json_for_post_request($response, $response->get_request_data(), $item, $contextid, $typeid);
+                    $response->set_content_type($this->formats[1]);
+                } catch (\Exception $e) {
+                    $response->set_code($e->getCode());
+                    $response->set_reason($e->getMessage());
+                }
+                break;
+            default:  // Should not be possible.
+                $response->set_code(405);
+                $response->set_reason("Invalid request method specified.");
+                return;
+        }
+        $response->set_body($json);
+    }
+
+    /**
+     * Generate the JSON for a POST request.
+     *
+     * @param \mod_lti\local\ltiservice\response $response Response object for this request.
+     * @param string $body POST body
+     * @param object $item Grade item instance
+     * @param string $contextid
+     * @param string $typeid
+     *
+     * @throws \Exception
+     */
+    private function get_json_for_post_request($response, $body, $item, $contextid, $typeid) {
+        $score = json_decode($body);
+        if (empty($score) ||
+                !isset($score->userId) ||
+                !isset($score->timestamp) ||
+                !isset($score->gradingProgress) ||
+                !isset($score->activityProgress) ||
+                !isset($score->timestamp) ||
+                isset($score->timestamp) && !gradebookservices::validate_iso8601_date($score->timestamp) ||
+                (isset($score->scoreGiven) && !is_numeric($score->scoreGiven)) ||
+                (isset($score->scoreMaximum) && !is_numeric($score->scoreMaximum)) ||
+                (!gradebookservices::is_user_gradable_in_course($contextid, $score->userId))
+                ) {
+            throw new \Exception('Incorrect score received' . $score, 400);
+        }
+        $score->timemodified = intval($score->timestamp);
+
+        if (!isset($score->scoreMaximum)) {
+            $score->scoreMaximum = 1;
+        }
+        $response->set_code(200);
+        $grade = \grade_grade::fetch(array('itemid' => $item->id, 'userid' => $score->userId));
+        if ($grade &&  !empty($grade->timemodified)) {
+            if ($grade->timemodified >= strtotime($score->timestamp)) {
+                $exmsg = "Refusing score with an earlier timestamp for item " . $item->id . " and user " . $score->userId;
+                throw new \Exception($exmsg, 409);
+            }
+        }
+        if (isset($score->scoreGiven)) {
+            if ($score->gradingProgress != 'FullyGraded') {
+                $score->scoreGiven = null;
+            }
+        }
+        gradebookservices::save_score($item, $score, $score->userId, $typeid);
+    }
+
+    /**
+     * get permissions from the config of the tool for that resource
+     *
+     * @param int $typeid
+     *
+     * @return array with the permissions related to this resource by the $lti_type or null if none.
+     */
+    public function get_permissions($typeid) {
+        $tool = lti_get_type_type_config($typeid);
+        if ($tool->ltiservice_gradesynchronization == '1') {
+            return array('Score.collection:post');
+        } else if ($tool->ltiservice_gradesynchronization == '2') {
+            return array('Score.collection:post');
+        } else {
+            return array();
+        }
+    }
+
+    /**
+     * Parse a value for custom parameter substitution variables.
+     *
+     * @param string $value String to be parsed
+     *
+     * @return string
+     */
+    public function parse_value($value) {
+        global $COURSE, $CFG;
+
+        if (strpos($value, '$Scores.url') !== false) {
+            require_once($CFG->libdir . '/gradelib.php');
+
+            $resolved = '';
+            $this->params['context_id'] = $COURSE->id;
+            $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
+            if (!empty($id)) {
+                $cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);
+                $id = $cm->instance;
+                $item = grade_get_grades($COURSE->id, 'mod', 'lti', $id);
+                if ($item && $item->items) {
+                    $this->params['item_id'] = $item->items[0]->id;
+                    $resolved = parent::get_endpoint();
+                }
+            }
+            $value = str_replace('$Scores.url', $resolved, $value);
+        }
+
+        return $value;
+    }
+}
diff --git a/mod/lti/service/gradebookservices/classes/local/service/gradebookservices.php b/mod/lti/service/gradebookservices/classes/local/service/gradebookservices.php
new file mode 100644
index 0000000000000..554f52549b880
--- /dev/null
+++ b/mod/lti/service/gradebookservices/classes/local/service/gradebookservices.php
@@ -0,0 +1,625 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file contains a class definition for the LTI Gradebook Services
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace ltiservice_gradebookservices\local\service;
+
+use ltiservice_gradebookservices\local\resources\lineitem;
+use ltiservice_gradebookservices\local\resources\lineitems;
+use ltiservice_gradebookservices\local\resources\results;
+use ltiservice_gradebookservices\local\resources\scores;
+use mod_lti\local\ltiservice\resource_base;
+use mod_lti\local\ltiservice\service_base;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * A service implementing LTI Gradebook Services.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class gradebookservices extends service_base {
+
+    /** Internal service name */
+    const SERVICE_NAME = 'ltiservice_gradebookservices';
+
+    /**
+     * Class constructor.
+     */
+    public function __construct() {
+
+        parent::__construct();
+        $this->id = 'gradebookservices';
+        $this->name = $this->get_string('servicename');
+
+    }
+
+    /**
+     * Get the resources for this service.
+     *
+     * @return resource_base[]
+     */
+    public function get_resources() {
+
+        // The containers should be ordered in the array after their elements.
+        // Lineitems should be after lineitem.
+        if (empty($this->resources)) {
+            $this->resources = array();
+            $this->resources[] = new lineitem($this);
+            $this->resources[] = new lineitems($this);
+            $this->resources[] = new results($this);
+            $this->resources[] = new scores($this);
+        }
+
+        return $this->resources;
+    }
+
+    /**
+     * Adds form elements for gradebook sync add/edit page.
+     *
+     * @param \MoodleQuickForm $mform Moodle quickform object definition
+     */
+    public function get_configuration_options(&$mform) {
+
+        $selectelementname = 'ltiservice_gradesynchronization';
+        $identifier = 'grade_synchronization';
+        $options = [
+            $this->get_string('nevergs'),
+            $this->get_string('partialgs'),
+            $this->get_string('alwaysgs')
+        ];
+
+        $mform->addElement('select', $selectelementname, $this->get_string($identifier), $options);
+        $mform->setType($selectelementname, 'int');
+        $mform->setDefault($selectelementname, 0);
+        $mform->addHelpButton($selectelementname, $identifier, self::SERVICE_NAME);
+    }
+
+    /**
+     * Retrieves string from lang file
+     *
+     * @param string $identifier
+     * @return string
+     */
+    private function get_string($identifier) {
+        return get_string($identifier, self::SERVICE_NAME);
+    }
+
+    /**
+     * Return an array with the names of the parameters that the service will be saving in the configuration
+     *
+     * @return array with the names of the parameters that the service will be saving in the configuration
+     *
+     */
+    public function get_configuration_parameter_names() {
+        return array('ltiservice_gradesynchronization');
+    }
+
+    /**
+     * Return an array of key/values to add to the launch parameters.
+     *
+     * @param string $messagetype 'basic-lti-launch-request' or 'ContentItemSelectionRequest'.
+     * @param string $courseid the course id.
+     * @param object $user The user id.
+     * @param string $typeid The tool lti type id.
+     * @param string $modlti The id of the lti activity.
+     *
+     * The type is passed to check the configuration
+     * and not return parameters for services not used.
+     *
+     * @return array of key/value pairs to add as launch parameters.
+     */
+    public function get_launch_parameters($messagetype, $courseid, $user, $typeid, $modlti = null) {
+        global $DB;
+
+        $launchparameters = array();
+        $tool = lti_get_type_type_config($typeid);
+        // Only inject parameters if the service is enabled for this tool.
+        if (isset($tool->ltiservice_gradesynchronization)) {
+            if ($tool->ltiservice_gradesynchronization == '1' || $tool->ltiservice_gradesynchronization == '2') {
+                // Check for used in context is only needed because there is no explicit site tool - course relation.
+                if ($this->is_allowed_in_context($typeid, $courseid)) {
+                    $endpoint = $this->get_service_path() . "/{$courseid}/lineitems";
+                    if (is_null($modlti)) {
+                        $id = null;
+                    } else {
+                        $conditions = array('courseid' => $courseid, 'itemtype' => 'mod',
+                                'itemmodule' => 'lti', 'iteminstance' => $modlti);
+
+                        $lineitems = $DB->get_records('grade_items', $conditions);
+                        $conditionsgbs = array('courseid' => $courseid, 'ltilinkid' => $modlti);
+                        $lineitemsgbs = $DB->get_records('ltiservice_gradebookservices', $conditionsgbs);
+                        if (count($lineitems) + count($lineitemsgbs) == 1) {
+                            if ($lineitems) {
+                                $lineitem = reset($lineitems);
+                                $id = $lineitem->id;
+                            } else {
+                                $lineitemsgb = reset($lineitemsgbs);
+                                $id = $lineitemsgb->gradeitemid;
+                            }
+                        } else {
+                            $id = null;
+                        }
+                    }
+                    $launchparameters['custom_lineitems_url'] = $endpoint . "?type_id={$typeid}";
+                    if (!is_null($id)) {
+                        $launchparameters['custom_lineitem_url'] = $endpoint . "/{$id}/lineitem?type_id={$typeid}";
+                    }
+                }
+            }
+        }
+        return $launchparameters;
+    }
+
+    /**
+     * Fetch the lineitem instances.
+     *
+     * @param string $courseid ID of course
+     * @param string $resourceid Resource identifier used for filtering, may be null
+     * @param string $ltilinkid Resource Link identifier used for filtering, may be null
+     * @param string $tag
+     * @param int $limitfrom Offset for the first line item to include in a paged set
+     * @param int $limitnum Maximum number of line items to include in the paged set
+     * @param string $typeid
+     *
+     * @return array
+     * @throws \Exception
+     */
+    public function get_lineitems($courseid, $resourceid, $ltilinkid, $tag, $limitfrom, $limitnum, $typeid) {
+        global $DB;
+
+        // Select all lti potential linetiems in site.
+        $params = array('courseid' => $courseid);
+
+        $optionalfilters = "";
+        if (isset($resourceid)) {
+            $optionalfilters .= " AND (i.idnumber = :resourceid)";
+            $params['resourceid'] = $resourceid;
+        }
+        $sql = "SELECT i.*
+                  FROM {grade_items} i
+                 WHERE (i.courseid = :courseid)
+                      {$optionalfilters}
+               ORDER BY i.id";
+        $lineitems = $DB->get_records_sql($sql, $params);
+
+        // For each one, check the gbs id, and check that toolproxy matches. If so, add the
+        // tag to the result and add it to a final results array.
+        $lineitemstoreturn = array();
+        $lineitemsandtotalcount = array();
+        if ($lineitems) {
+            foreach ($lineitems as $lineitem) {
+                $gbs = $this->find_ltiservice_gradebookservice_for_lineitem($lineitem->id);
+                if ($gbs && (!isset($tag) || (isset($tag) && $gbs->tag == $tag))
+                        && (!isset($ltilinkid) || (isset($ltilinkid) && $gbs->ltilinkid == $ltilinkid))) {
+                    if (is_null($typeid)) {
+                        if ($this->get_tool_proxy()->id == $gbs->toolproxyid) {
+                            array_push($lineitemstoreturn, $lineitem);
+                        }
+                    } else {
+                        if ($typeid == $gbs->typeid) {
+                            array_push($lineitemstoreturn, $lineitem);
+                        }
+                    }
+                } else if (($lineitem->itemtype == 'mod') && ($lineitem->itemmodule == 'lti') && (!isset($tag) &&
+                        (!isset($ltilinkid) || (isset($ltilinkid) && $lineitem->iteminstance == $ltilinkid)))) {
+                    // We will need to check if the activity related belongs to our tool proxy.
+                    $ltiactivity = $DB->get_record('lti', array('id' => $lineitem->iteminstance));
+                    if (($ltiactivity) && (isset($ltiactivity->typeid))) {
+                        if ($ltiactivity->typeid != 0) {
+                            $tool = $DB->get_record('lti_types', array('id' => $ltiactivity->typeid));
+                        } else {
+                            $tool = lti_get_tool_by_url_match($ltiactivity->toolurl, $courseid);
+                            if (!$tool) {
+                                $tool = lti_get_tool_by_url_match($ltiactivity->securetoolurl, $courseid);
+                            }
+                        }
+                        if (is_null($typeid)) {
+                            if (($tool) && ($this->get_tool_proxy()->id == $tool->toolproxyid)) {
+                                array_push($lineitemstoreturn, $lineitem);
+                            }
+                        } else {
+                            if (($tool) && ($tool->id == $typeid)) {
+                                array_push($lineitemstoreturn, $lineitem);
+                            }
+                        }
+                    }
+                }
+            }
+            $lineitemsandtotalcount = array();
+            array_push($lineitemsandtotalcount, count($lineitemstoreturn));
+            // Return the right array based in the paging parameters limit and from.
+            if (($limitnum) && ($limitnum > 0)) {
+                $lineitemstoreturn = array_slice($lineitemstoreturn, $limitfrom, $limitnum);
+            }
+            array_push($lineitemsandtotalcount, $lineitemstoreturn);
+        }
+        return $lineitemsandtotalcount;
+    }
+
+    /**
+     * Fetch a lineitem instance.
+     *
+     * Returns the lineitem instance if found, otherwise false.
+     *
+     * @param string $courseid ID of course
+     * @param string $itemid ID of lineitem
+     * @param string $typeid
+     *
+     * @return \ltiservice_gradebookservices\local\resources\lineitem|bool
+     */
+    public function get_lineitem($courseid, $itemid, $typeid) {
+        global $DB, $CFG;
+
+        require_once($CFG->libdir . '/gradelib.php');
+        $lineitem = \grade_item::fetch(array('id' => $itemid));
+        if ($lineitem) {
+            $gbs = $this->find_ltiservice_gradebookservice_for_lineitem($itemid);
+            if (!$gbs) {
+                // We will need to check if the activity related belongs to our tool proxy.
+                $ltiactivity = $DB->get_record('lti', array('id' => $lineitem->iteminstance));
+                if (($ltiactivity) && (isset($ltiactivity->typeid))) {
+                    if ($ltiactivity->typeid != 0) {
+                        $tool = $DB->get_record('lti_types', array('id' => $ltiactivity->typeid));
+                    } else {
+                        $tool = lti_get_tool_by_url_match($ltiactivity->toolurl, $courseid);
+                        if (!$tool) {
+                            $tool = lti_get_tool_by_url_match($ltiactivity->securetoolurl, $courseid);
+                        }
+                    }
+                    if (is_null($typeid)) {
+                        if (!(($tool) && ($this->get_tool_proxy()->id == $tool->toolproxyid))) {
+                            return false;
+                        }
+                    } else {
+                        if (!(($tool) && ($tool->id == $typeid))) {
+                            return false;
+                        }
+                    }
+                } else {
+                    return false;
+                }
+            }
+        }
+        return $lineitem;
+    }
+
+
+    /**
+     * Set a grade item.
+     *
+     * @param object $gradeitem Grade Item record
+     * @param object $score Result object
+     * @param int $userid User ID
+     *
+     * @throws \Exception
+     */
+    public static function save_score($gradeitem, $score, $userid) {
+        global $DB, $CFG;
+        $source = 'mod' . self::SERVICE_NAME;
+        if ($DB->get_record('user', array('id' => $userid)) === false) {
+            throw new \Exception(null, 400);
+        }
+        require_once($CFG->libdir . '/gradelib.php');
+        $finalgrade = null;
+        $timemodified = null;
+        if (isset($score->scoreGiven) && $score->scoreGiven) {
+            $finalgrade = grade_floatval($score->scoreGiven);
+            $max = 1;
+            if (isset($score->scoreMaximum)) {
+                $max = $score->scoreMaximum;
+            }
+            if (!is_null($max) && grade_floats_different($max, $gradeitem->grademax) && grade_floats_different($max, 0.0)) {
+                // Rescale to match the grade item maximum.
+                $finalgrade = grade_floatval($finalgrade * $gradeitem->grademax / $max);
+            }
+            if (isset($score->timestamp)) {
+                $timemodified = strtotime($score->timestamp);
+            } else {
+                $timemodified = time();
+            }
+        }
+        $feedbackformat = FORMAT_MOODLE;
+        $feedback = null;
+        if (isset($score->comment) && !empty($score->comment)) {
+            $feedback = $score->comment;
+            $feedbackformat = FORMAT_PLAIN;
+        }
+
+        if (!$grade = \grade_grade::fetch(array('itemid' => $gradeitem->id, 'userid' => $userid))) {
+            $grade = new \grade_grade();
+            $grade->userid = $userid;
+            $grade->itemid = $gradeitem->id;
+        }
+        $grade->rawgrademax = $score->scoreMaximum;
+        $grade->timemodified = $timemodified;
+        $grade->feedbackformat = $feedbackformat;
+        $grade->feedback = $feedback;
+        if ($gradeitem->is_manual_item()) {
+            $grade->finalgrade = $finalgrade;
+            if (empty($grade->id)) {
+                $result = (bool)$grade->insert($source);
+            } else {
+                $result = $grade->update($source);
+            }
+        } else {
+            $grade->rawgrade = $finalgrade;
+            $status = \grade_update($source, $gradeitem->courseid,
+                         $gradeitem->itemtype, $gradeitem->itemmodule,
+                         $gradeitem->iteminstance, $gradeitem->itemnumber,
+                         $grade);
+
+            $result = ($status == GRADE_UPDATE_OK);
+        }
+        if (!$result) {
+            debugging("failed to save score for item ".$gradeitem->id." and user ".$grade->userid);
+            throw new \Exception(null, 500);
+        }
+
+    }
+
+    /**
+     * Get the json object representation of the grade item
+     *
+     * @param object $item Grade Item record
+     * @param string $endpoint Endpoint for lineitems container request
+     * @param string $typeid
+     *
+     * @return object
+     */
+    public static function item_for_json($item, $endpoint, $typeid) {
+
+        $lineitem = new \stdClass();
+        if (is_null($typeid)) {
+            $typeidstring = "";
+        } else {
+            $typeidstring = "?type_id={$typeid}";
+        }
+        $lineitem->id = "{$endpoint}/{$item->id}/lineitem" . $typeidstring;
+        $lineitem->label = $item->itemname;
+        $lineitem->scoreMaximum = floatval($item->grademax);
+        $lineitem->resourceId = (!empty($item->idnumber)) ? $item->idnumber : '';
+        $gbs = self::find_ltiservice_gradebookservice_for_lineitem($item->id);
+        if ($gbs) {
+            $lineitem->tag = (!empty($gbs->tag)) ? $gbs->tag : '';
+            if (isset($gbs->ltilinkid)) {
+                $lineitem->ltiLinkId = strval($gbs->ltilinkid);
+            }
+        } else {
+            $lineitem->tag = '';
+            if (isset($item->iteminstance)) {
+                $lineitem->ltiLinkId = strval($item->iteminstance);
+            }
+        }
+
+        return $lineitem;
+
+    }
+
+    /**
+     * Get the object matching the JSON representation of the result.
+     *
+     * @param object  $grade              Grade record
+     * @param string  $endpoint           Endpoint for lineitem
+     * @param int  $typeid                The id of the type to include in the result url.
+     *
+     * @return object
+     */
+    public static function result_for_json($grade, $endpoint, $typeid) {
+
+        if (is_null($typeid)) {
+            $id = "{$endpoint}/results?user_id={$grade->userid}";
+        } else {
+            $id = "{$endpoint}/results?type_id={$typeid}&user_id={$grade->userid}";
+        }
+        $result = new \stdClass();
+        $result->id = $id;
+        $result->userId = $grade->userid;
+        if (!empty($grade->finalgrade)) {
+            $result->resultScore = floatval($grade->finalgrade);
+            $result->resultMaximum = floatval($grade->rawgrademax);
+            if (!empty($grade->feedback)) {
+                $result->comment = $grade->feedback;
+            }
+            if (is_null($typeid)) {
+                $result->scoreOf = $endpoint;
+            } else {
+                $result->scoreOf = "{$endpoint}?type_id={$typeid}";
+            }
+            $result->timestamp = date('c', $grade->timemodified);
+        }
+        return $result;
+    }
+
+    /**
+     * Check if an LTI id is valid.
+     *
+     * @param string $linkid             The lti id
+     * @param string  $course            The course
+     * @param string  $toolproxy         The tool proxy id
+     *
+     * @return boolean
+     */
+    public static function check_lti_id($linkid, $course, $toolproxy) {
+        global $DB;
+        // Check if lti type is zero or not (comes from a backup).
+        $sqlparams1 = array();
+        $sqlparams1['linkid'] = $linkid;
+        $sqlparams1['course'] = $course;
+        $ltiactivity = $DB->get_record('lti', array('id' => $linkid, 'course' => $course));
+        if ($ltiactivity->typeid == 0) {
+            $tool = lti_get_tool_by_url_match($ltiactivity->toolurl, $course);
+            if (!$tool) {
+                $tool = lti_get_tool_by_url_match($ltiactivity->securetoolurl, $course);
+            }
+            return (($tool) && ($toolproxy == $tool->toolproxyid));
+        } else {
+            $sqlparams2 = array();
+            $sqlparams2['linkid'] = $linkid;
+            $sqlparams2['course'] = $course;
+            $sqlparams2['toolproxy'] = $toolproxy;
+            $sql = 'SELECT lti.*
+                      FROM {lti} lti
+                INNER JOIN {lti_types} typ ON lti.typeid = typ.id
+                     WHERE lti.id = ?
+                           AND lti.course = ?
+                           AND typ.toolproxyid = ?';
+            return $DB->record_exists_sql($sql, $sqlparams2);
+        }
+    }
+
+    /**
+     * Check if an LTI id is valid when we are in a LTI 1.x case
+     *
+     * @param string $linkid             The lti id
+     * @param string  $course            The course
+     * @param string  $typeid            The lti type id
+     *
+     * @return boolean
+     */
+    public static function check_lti_1x_id($linkid, $course, $typeid) {
+        global $DB;
+        // Check if lti type is zero or not (comes from a backup).
+        $sqlparams1 = array();
+        $sqlparams1['linkid'] = $linkid;
+        $sqlparams1['course'] = $course;
+        $ltiactivity = $DB->get_record('lti', array('id' => $linkid, 'course' => $course));
+        if ($ltiactivity) {
+            if ($ltiactivity->typeid == 0) {
+                $tool = lti_get_tool_by_url_match($ltiactivity->toolurl, $course);
+                if (!$tool) {
+                    $tool = lti_get_tool_by_url_match($ltiactivity->securetoolurl, $course);
+                }
+                return (($tool) && ($typeid == $tool->id));
+            } else {
+                $sqlparams2 = array();
+                $sqlparams2['linkid'] = $linkid;
+                $sqlparams2['course'] = $course;
+                $sqlparams2['typeid'] = $typeid;
+                $sql = 'SELECT lti.*
+                          FROM {lti} lti
+                    INNER JOIN {lti_types} typ ON lti.typeid = typ.id
+                         WHERE lti.id = ?
+                               AND lti.course = ?
+                               AND typ.id = ?';
+                return $DB->record_exists_sql($sql, $sqlparams2);
+            }
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * Deletes orphaned rows from the 'ltiservice_gradebookservices' table.
+     *
+     * Sometimes, if a gradebook entry is deleted and it was a lineitem
+     * the row in the table ltiservice_gradebookservices can become an orphan
+     * This method will clean these orphans. It will happens based on a task
+     * because it is not urgent and we don't want to slow the service
+     */
+    public static function delete_orphans_ltiservice_gradebookservices_rows() {
+        global $DB;
+
+        $sql = "DELETE
+                  FROM {ltiservice_gradebookservices}
+                 WHERE gradeitemid NOT IN (SELECT id
+                                             FROM {grade_items} gi
+                                            WHERE gi.itemtype = 'mod'
+                                              AND gi.itemmodule = 'lti')";
+        $DB->execute($sql);
+    }
+
+    /**
+     * Check if a user can be graded in a course
+     *
+     * @param int $courseid The course
+     * @param int $userid The user
+     * @return bool
+     */
+    public static function is_user_gradable_in_course($courseid, $userid) {
+        global $CFG;
+
+        $gradableuser = false;
+        $coursecontext = \context_course::instance($courseid);
+        if (is_enrolled($coursecontext, $userid, '', false)) {
+            $roles = get_user_roles($coursecontext, $userid);
+            $gradebookroles = explode(',', $CFG->gradebookroles);
+            foreach ($roles as $role) {
+                foreach ($gradebookroles as $gradebookrole) {
+                    if ($role->roleid = $gradebookrole) {
+                        $gradableuser = true;
+                    }
+                }
+            }
+        }
+
+        return $gradableuser;
+    }
+
+    /**
+     * Find the right element in the ltiservice_gradebookservice table for a lineitem
+     *
+     * @param string $lineitemid            The lineitem
+     * @return object|bool gradebookservice id or false if none
+     */
+    public static function find_ltiservice_gradebookservice_for_lineitem($lineitemid) {
+        global $DB;
+
+        if (!$lineitemid) {
+            return false;
+        }
+        $gradeitem = $DB->get_record('grade_items', array('id' => $lineitemid));
+        if ($gradeitem) {
+            $gbs = $DB->get_record('ltiservice_gradebookservices',
+                    array('gradeitemid' => $gradeitem->id, 'courseid' => $gradeitem->courseid));
+            if ($gbs) {
+                return $gbs;
+            } else {
+                return false;
+            }
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * Validates specific ISO 8601 format of the timestamps.
+     *
+     * @param string $date The timestamp to check.
+     * @return boolean true or false if the date matches the format.
+     *
+     */
+    public static function validate_iso8601_date($date) {
+        if (preg_match('/^([\+-]?\d{4}(?!\d{2}\b))((-?)((0[1-9]|1[0-2])' .
+                '(\3([12]\d|0[1-9]|3[01]))?|W([0-4]\d|5[0-2])(-?[1-7])?|(00[1-9]|0[1-9]\d|[12]\d{2}|3([0-5]\d|6[1-6])))' .
+                '([T\s]((([01]\d|2[0-3])((:?)[0-5]\d)?|24\:?00)([\.,]\d+(?!:))?)?(\17[0-5]\d([\.,]\d+)?)' .
+                '?([zZ]|([\+-])([01]\d|2[0-3]):?([0-5]\d)?)?)?)?$/', $date) > 0) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+}
diff --git a/mod/lti/service/gradebookservices/classes/task/cleanup_task.php b/mod/lti/service/gradebookservices/classes/task/cleanup_task.php
new file mode 100644
index 0000000000000..6737bcf83e3dd
--- /dev/null
+++ b/mod/lti/service/gradebookservices/classes/task/cleanup_task.php
@@ -0,0 +1,58 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * A scheduled task for gradebookservices.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+namespace ltiservice_gradebookservices\task;
+
+use core\task\scheduled_task;
+use ltiservice_gradebookservices\local\service\gradebookservices;
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Class containing the scheduled task for gradebookservices.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class cleanup_task extends scheduled_task {
+
+    /**
+     * Get a descriptive name for this task (shown to admins).
+     *
+     * @return string
+     */
+    public function get_name() {
+        return get_string('taskcleanup', 'ltiservice_gradebookservices');
+    }
+
+    /**
+     * Run forum cron.
+     */
+    public function execute() {
+        gradebookservices::delete_orphans_ltiservice_gradebookservices_rows();
+    }
+
+}
diff --git a/mod/lti/service/gradebookservices/db/install.xml b/mod/lti/service/gradebookservices/db/install.xml
new file mode 100644
index 0000000000000..73e8431b94120
--- /dev/null
+++ b/mod/lti/service/gradebookservices/db/install.xml
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<XMLDB PATH="mod/lti/service/gradebookservices/db" VERSION="20150915" COMMENT="XMLDB file for Moodle mod/lti/service/gradebookservices"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:noNamespaceSchemaLocation="../../../../../lib/xmldb/xmldb.xsd"
+>
+  <TABLES>
+    <TABLE NAME="ltiservice_gradebookservices" COMMENT="This file records the grade items created by the LTI Gradebook Services service">
+      <FIELDS>
+        <FIELD NAME="id" TYPE="int" LENGTH="10" NOTNULL="true" SEQUENCE="true"/>
+        <FIELD NAME="gradeitemid" TYPE="int" LENGTH="10" NOTNULL="true" SEQUENCE="false" COMMENT="ID of the gradeItem related."/>
+        <FIELD NAME="courseid" TYPE="int" LENGTH="10" NOTNULL="true" SEQUENCE="false" COMMENT="ID of the course related."/>
+        <FIELD NAME="toolproxyid" TYPE="int" LENGTH="10" NOTNULL="false" SEQUENCE="false" COMMENT="ID of the Tool Proxy instance."/>
+        <FIELD NAME="typeid" TYPE="int" LENGTH="10" NOTNULL="false" SEQUENCE="false" COMMENT="ID of the LTI Type if not Proxy."/>
+        <FIELD NAME="baseurl" TYPE="text" NOTNULL="false" SEQUENCE="false" COMMENT="Lineitem URL that will be returned to the Tool provider"/>
+        <FIELD NAME="ltilinkid" TYPE="int" LENGTH="10" NOTNULL="false" SEQUENCE="false" COMMENT="ID of the LTI element related with this lineitem."/>
+        <FIELD NAME="tag" TYPE="char" LENGTH="255" NOTNULL="false" SEQUENCE="false" COMMENT="Tag type specified for the line item"/>
+      </FIELDS>
+      <KEYS>
+        <KEY NAME="primary" TYPE="primary" FIELDS="id"/>
+        <KEY NAME="ltilinkid" TYPE="foreign" FIELDS="ltilinkid" REFTABLE="lti" REFFIELDS="id" COMMENT="The ID of the LTI element related with this lineitem."/>
+        <KEY NAME="itemnumbercourse" TYPE="foreign" FIELDS="gradeitemid,courseid" REFTABLE="grade_items" REFFIELDS="id,courseid" COMMENT="The row in gradeitems"/>
+      </KEYS>
+    </TABLE>
+  </TABLES>
+</XMLDB>
diff --git a/mod/lti/service/gradebookservices/db/tasks.php b/mod/lti/service/gradebookservices/db/tasks.php
new file mode 100644
index 0000000000000..9515b9ea2f96c
--- /dev/null
+++ b/mod/lti/service/gradebookservices/db/tasks.php
@@ -0,0 +1,39 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This file defines tasks performed by the plugin.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+// List of tasks.
+$tasks = array(
+    array(
+        'classname' => 'ltiservice_gradebookservices\task\cleanup_task',
+        'blocking' => 0,
+        'minute' => 'R',
+        'hour' => 'R',
+        'day' => '*',
+        'dayofweek' => '*',
+        'month' => '*'
+    )
+);
diff --git a/mod/lti/service/gradebookservices/lang/en/ltiservice_gradebookservices.php b/mod/lti/service/gradebookservices/lang/en/ltiservice_gradebookservices.php
new file mode 100644
index 0000000000000..8d0a6ae7c6d24
--- /dev/null
+++ b/mod/lti/service/gradebookservices/lang/en/ltiservice_gradebookservices.php
@@ -0,0 +1,38 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Strings for component 'ltiservice_gradebookservices', language 'en'
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+$string['alwaysgs'] = 'Use this service for grade sync and column management ';
+$string['grade_synchronization'] = 'IMS LTI Assignment and Grade Services: ';
+$string['grade_synchronization_help'] = 'Use the IMS LTI Assignment and Grade Service to synchronize the grades instead Basic Outcomes.
+
+* **Do not use this service** -  This will use the basic outcomes features and configuration
+* **Use this service for grade sync only** - The service will populate the grades in an already existing gradebook column, but it will not be able to create new columns
+* **Use this service for grade sync and column management** -  The service will be able to create and update gradebook columns and manage the grades. ';
+$string['modulename'] = 'LTI Grades';
+$string['nevergs'] = 'Do not use this service';
+$string['partialgs'] = 'Use this service for grade sync only';
+$string['pluginname'] = 'LTI Assignment and Grade Services';
+$string['servicename'] = 'LTI Assignment and Grade Services';
+$string['taskcleanup'] = 'LTI Assignment and Grade Services table cleanup';
diff --git a/mod/lti/service/gradebookservices/tests/task_cleanup_test.php b/mod/lti/service/gradebookservices/tests/task_cleanup_test.php
new file mode 100644
index 0000000000000..20881e0ef5a72
--- /dev/null
+++ b/mod/lti/service/gradebookservices/tests/task_cleanup_test.php
@@ -0,0 +1,103 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Tests cleaning up the gradebook services task.
+ *
+ * @package ltiservice_gradebookservices
+ * @category test
+ * @copyright 2018 Mark Nelson <markn@moodle.com>
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Tests cleaning up the gradebook services task.
+ *
+ * @package ltiservice_gradebookservices
+ * @category test
+ * @copyright 2018 Mark Nelson <markn@moodle.com>
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class ltiservice_gradebookservices_cleanup_task_testcase extends advanced_testcase {
+
+    /**
+     * Test set up.
+     *
+     * This is executed before running any test in this file.
+     */
+    public function setUp() {
+        $this->resetAfterTest();
+    }
+
+    /**
+     * Test the cleanup task.
+     */
+    public function test_cleanup_task() {
+        global $DB;
+
+        // Create a course.
+        $course = $this->getDataGenerator()->create_course();
+
+        // Create a few LTI items.
+        $lti = $this->getDataGenerator()->create_module('lti', ['course' => $course->id]);
+        $lti2 = $this->getDataGenerator()->create_module('lti', ['course' => $course->id]);
+
+        $conditions = [
+            'courseid' => $course->id,
+            'itemtype' => 'mod',
+            'itemmodule' => 'lti',
+            'iteminstance' => $lti->id
+        ];
+
+        // Get the grade items.
+        $gradeitem = $DB->get_record('grade_items', $conditions);
+
+        $conditions['iteminstance'] = $lti2->id;
+        $gradeitem2 = $DB->get_record('grade_items', $conditions);
+
+        // Insert these into the 'ltiservice_gradebookservices' table.
+        $data = new stdClass();
+        $data->gradeitemid = $gradeitem->id;
+        $data->courseid = $course->id;
+        $DB->insert_record('ltiservice_gradebookservices', $data);
+
+        $data->gradeitemid = $gradeitem2->id;
+        $DB->insert_record('ltiservice_gradebookservices', $data);
+
+        $task = new \ltiservice_gradebookservices\task\cleanup_task();
+        $task->execute();
+
+        // Check they both still exist.
+        $this->assertEquals(2, $DB->count_records('ltiservice_gradebookservices'));
+
+        // Delete the first LTI activity.
+        course_delete_module($lti->cmid);
+
+        // Run the task again.
+        $task = new \ltiservice_gradebookservices\task\cleanup_task();
+        $task->execute();
+
+        // Check only the second grade item exists.
+        $gradebookserviceitems = $DB->get_records('ltiservice_gradebookservices');
+        $this->assertCount(1, $gradebookserviceitems);
+
+        $gradebookserviceitem = reset($gradebookserviceitems);
+
+        $this->assertEquals($gradeitem2->id, $gradebookserviceitem->gradeitemid);
+    }
+}
diff --git a/mod/lti/service/gradebookservices/version.php b/mod/lti/service/gradebookservices/version.php
new file mode 100644
index 0000000000000..6afb647969f46
--- /dev/null
+++ b/mod/lti/service/gradebookservices/version.php
@@ -0,0 +1,30 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Version information for the ltiservice_gradebookservices service.
+ *
+ * @package    ltiservice_gradebookservices
+ * @copyright  2017 Cengage Learning http://www.cengage.com
+ * @author     Dirk Singels, Diego del Blanco, Claude Vervoort
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+$plugin->version   = 2018011100;
+$plugin->requires  = 2018010100;
+$plugin->component = 'ltiservice_gradebookservices';
diff --git a/mod/lti/service/memberships/classes/local/resources/contextmemberships.php b/mod/lti/service/memberships/classes/local/resources/contextmemberships.php
index 7afb386fc0758..8536934909474 100644
--- a/mod/lti/service/memberships/classes/local/resources/contextmemberships.php
+++ b/mod/lti/service/memberships/classes/local/resources/contextmemberships.php
@@ -26,8 +26,9 @@
 
 namespace ltiservice_memberships\local\resources;
 
-use \mod_lti\local\ltiservice\service_base;
+use mod_lti\local\ltiservice\resource_base;
 use ltiservice_memberships\local\service\memberships;
+use core_availability\info_module;
 
 defined('MOODLE_INTERNAL') || die();
 
@@ -39,18 +40,18 @@
  * @copyright  2015 Vital Source Technologies http://vitalsource.com
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class contextmemberships extends \mod_lti\local\ltiservice\resource_base {
+class contextmemberships extends resource_base {
 
     /**
      * Class constructor.
      *
-     * @param ltiservice_memberships\local\service\memberships $service Service instance
+     * @param \ltiservice_memberships\local\service\memberships $service Service instance
      */
     public function __construct($service) {
 
         parent::__construct($service);
         $this->id = 'ToolProxyBindingMemberships';
-        $this->template = '/{context_type}/{context_id}/bindings/{vendor_code}/{product_code}/{tool_code}/memberships';
+        $this->template = '/{context_type}/{context_id}/bindings/{tool_code}/memberships';
         $this->variables[] = 'ToolProxyBinding.memberships.url';
         $this->formats[] = 'application/vnd.ims.lis.v2.membershipcontainer+json';
         $this->methods[] = 'GET';
@@ -60,23 +61,24 @@ public function __construct($service) {
     /**
      * Execute the request for this resource.
      *
-     * @param mod_lti\local\ltiservice\response $response  Response object for this request.
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
      */
     public function execute($response) {
-        global $CFG, $DB;
+        global $DB;
 
         $params = $this->parse_template();
         $role = optional_param('role', '', PARAM_TEXT);
         $limitnum = optional_param('limit', 0, PARAM_INT);
         $limitfrom = optional_param('from', 0, PARAM_INT);
+        $linkid = optional_param('rlid', '', PARAM_TEXT);
+        $lti = null;
+        $modinfo = null;
+
         if ($limitnum <= 0) {
             $limitfrom = 0;
         }
 
         try {
-            if (!$this->get_service()->check_tool_proxy($params['product_code'])) {
-                throw new \Exception(null, 401);
-            }
             if (!($course = $DB->get_record('course', array('id' => $params['context_id']), 'id', IGNORE_MISSING))) {
                 throw new \Exception(null, 404);
             }
@@ -84,14 +86,33 @@ public function execute($response) {
                 throw new \Exception(null, 404);
             }
             if (!($tool = $DB->get_record('lti_types', array('id' => $params['tool_code']),
-                                    'toolproxyid,enabledcapability,parameter', IGNORE_MISSING))) {
+                                    'id,toolproxyid,enabledcapability,parameter', IGNORE_MISSING))) {
                 throw new \Exception(null, 404);
             }
-            $toolproxy = $DB->get_record('lti_tool_proxies', array('id' => $tool->toolproxyid), 'guid', IGNORE_MISSING);
-            if (!$toolproxy || ($toolproxy->guid !== $this->get_service()->get_tool_proxy()->guid)) {
-                throw new \Exception(null, 400);
+            if (!empty($linkid)) {
+                if (!($lti = $DB->get_record('lti', array('id' => $linkid), 'id,course,typeid,servicesalt', IGNORE_MISSING))) {
+                    throw new \Exception(null, 404);
+                }
+                $modinfo = get_fast_modinfo($course);
+                $cm = get_coursemodule_from_instance('lti', $linkid, $lti->course, false, MUST_EXIST);
+                $cm = $modinfo->get_cm($cm->id);
+                $modinfo = new info_module($cm);
+                if ($modinfo->is_available_for_all()) {
+                    $modinfo = null;
+                }
             }
-            $json = memberships::get_users_json($this, $context, $course->id, $tool, $role, $limitfrom, $limitnum, null, null);
+            if ($tool->toolproxyid == 0) {
+                if (!$this->check_type($params['tool_code'], $params['context_id'],
+                        'ToolProxyBinding.memberships.url:get', null)) {
+                    throw new \Exception(null, 403);
+                }
+            } else {
+                $toolproxy = $DB->get_record('lti_tool_proxies', array('id' => $tool->toolproxyid), 'guid', IGNORE_MISSING);
+                if (!$this->check_tool_proxy($toolproxy->guid, $response->get_request_data())) {
+                    throw new \Exception(null, 403);
+                }
+            }
+            $json = memberships::get_users_json($this, $context, $course->id, $tool, $role, $limitfrom, $limitnum, $lti, $modinfo);
 
             $response->set_content_type($this->formats[0]);
             $response->set_body($json);
@@ -101,6 +122,21 @@ public function execute($response) {
         }
     }
 
+    /**
+     * get permissions from the config of the tool for that resource
+     *
+     * @param int $typeid
+     * @return array with the permissions related to this resource by the $lti_type or null if none.
+     */
+    public function get_permissions($typeid) {
+        $tool = lti_get_type_type_config($typeid);
+        if ($tool->ltiservice_memberships == '1') {
+            return array('ToolProxyBinding.memberships.url:get');
+        } else {
+            return array();
+        }
+    }
+
     /**
      * Parse a value for custom parameter substitution variables.
      *
@@ -111,25 +147,24 @@ public function execute($response) {
     public function parse_value($value) {
         global $COURSE, $DB;
 
-        if ($COURSE->id === SITEID) {
-            $this->params['context_type'] = 'Group';
-        } else {
-            $this->params['context_type'] = 'CourseSection';
-        }
-        $this->params['context_id'] = $COURSE->id;
-        $this->params['vendor_code'] = $this->get_service()->get_tool_proxy()->vendorcode;
-        $this->params['product_code'] = $this->get_service()->get_tool_proxy()->guid;
-
-        $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
-        if (!empty($id)) {
-            $cm = get_coursemodule_from_id('lti', $id, 0, false, IGNORE_MISSING);
-            $lti = $DB->get_record('lti', array('id' => $cm->instance), 'typeid', IGNORE_MISSING);
-            if ($lti && !empty($lti->typeid)) {
-                $this->params['tool_code'] = $lti->typeid;
+        if (strpos($value, '$ToolProxyBinding.memberships.url') !== false) {
+            if ($COURSE->id === SITEID) {
+                $this->params['context_type'] = 'Group';
+            } else {
+                $this->params['context_type'] = 'CourseSection';
+            }
+            $this->params['context_id'] = $COURSE->id;
+
+            $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
+            if (!empty($id)) {
+                $cm = get_coursemodule_from_id('lti', $id, 0, false, IGNORE_MISSING);
+                $lti = $DB->get_record('lti', array('id' => $cm->instance), 'typeid', IGNORE_MISSING);
+                if ($lti && !empty($lti->typeid)) {
+                    $this->params['tool_code'] = $lti->typeid;
+                }
             }
+            $value = str_replace('$ToolProxyBinding.memberships.url', parent::get_endpoint(), $value);
         }
-        $value = str_replace('$ToolProxyBinding.memberships.url', parent::get_endpoint(), $value);
-
         return $value;
 
     }
diff --git a/mod/lti/service/memberships/classes/local/resources/linkmemberships.php b/mod/lti/service/memberships/classes/local/resources/linkmemberships.php
index 10efc244ec3c6..621a3dd0a9045 100644
--- a/mod/lti/service/memberships/classes/local/resources/linkmemberships.php
+++ b/mod/lti/service/memberships/classes/local/resources/linkmemberships.php
@@ -26,27 +26,29 @@
 
 namespace ltiservice_memberships\local\resources;
 
-use \mod_lti\local\ltiservice\service_base;
+use mod_lti\local\ltiservice\resource_base;
 use ltiservice_memberships\local\service\memberships;
-use core_availability\info;
 use core_availability\info_module;
 
 defined('MOODLE_INTERNAL') || die();
 
 /**
  * A resource implementing Link Memberships.
+ * The link membership is no longer defined in the published
+ * version of the LTI specification. It is replaced by the
+ * rlid parameter in the context membership URL.
  *
  * @package    ltiservice_memberships
  * @since      Moodle 3.0
  * @copyright  2015 Vital Source Technologies http://vitalsource.com
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class linkmemberships extends \mod_lti\local\ltiservice\resource_base {
+class linkmemberships extends resource_base {
 
     /**
      * Class constructor.
      *
-     * @param ltiservice_memberships\local\service\memberships $service Service instance
+     * @param \ltiservice_memberships\local\service\memberships $service Service instance
      */
     public function __construct($service) {
 
@@ -62,55 +64,77 @@ public function __construct($service) {
     /**
      * Execute the request for this resource.
      *
-     * @param mod_lti\local\ltiservice\response $response  Response object for this request.
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
      */
     public function execute($response) {
-        global $CFG, $DB;
+        global $DB;
 
         $params = $this->parse_template();
         $linkid = $params['link_id'];
         $role = optional_param('role', '', PARAM_TEXT);
         $limitnum = optional_param('limit', 0, PARAM_INT);
         $limitfrom = optional_param('from', 0, PARAM_INT);
+
         if ($limitnum <= 0) {
             $limitfrom = 0;
         }
 
-        try {
-            if (empty($linkid)) {
-                throw new \Exception(null, 404);
-            }
-            if (!($lti = $DB->get_record('lti', array('id' => $linkid), 'id,course,typeid,servicesalt', IGNORE_MISSING))) {
-                throw new \Exception(null, 404);
+        if (empty($linkid)) {
+            $response->set_code(404);
+            return;
+        }
+        if (!($lti = $DB->get_record('lti', array('id' => $linkid), 'id,course,typeid,servicesalt', IGNORE_MISSING))) {
+            $response->set_code(404);
+            return;
+        }
+        $tool = $DB->get_record('lti_types', array('id' => $lti->typeid));
+        if ($tool->toolproxyid == 0) { // We wil use the same permission for this and contextmembers.
+            if (!$this->check_type($lti->typeid, $lti->course, 'ToolProxyBinding.memberships.url:get', null)) {
+                $response->set_code(403);
+                return;
             }
-            $tool = $DB->get_record('lti_types', array('id' => $lti->typeid));
+        } else {
             $toolproxy = $DB->get_record('lti_tool_proxies', array('id' => $tool->toolproxyid));
             if (!$this->check_tool_proxy($toolproxy->guid, $response->get_request_data())) {
-                throw new \Exception(null, 401);
-            }
-            if (!($course = $DB->get_record('course', array('id' => $lti->course), 'id', IGNORE_MISSING))) {
-                throw new \Exception(null, 404);
+                $response->set_code(403);
+                return;
             }
-            if (!($context = \context_course::instance($lti->course))) {
-                throw new \Exception(null, 404);
-            }
-            $modinfo = get_fast_modinfo($course);
-            $cm = get_coursemodule_from_instance('lti', $linkid, $lti->course, false, MUST_EXIST);
-            $cm = $modinfo->get_cm($cm->id);
-            $info = new info_module($cm);
-            if ($info->is_available_for_all()) {
-                $info = null;
-            }
-
-            $json = memberships::get_users_json($this, $context, $lti->course, $tool, $role, $limitfrom, $limitnum, $lti, $info);
+        }
+        if (!($course = $DB->get_record('course', array('id' => $lti->course), 'id', IGNORE_MISSING))) {
+            $response->set_code(404);
+            return;
+        }
+        if (!($context = \context_course::instance($lti->course))) {
+            $response->set_code(404);
+            return;
+        }
+        $modinfo = get_fast_modinfo($course);
+        $cm = get_coursemodule_from_instance('lti', $linkid, $lti->course, false, MUST_EXIST);
+        $cm = $modinfo->get_cm($cm->id);
+        $info = new info_module($cm);
+        if ($info->is_available_for_all()) {
+            $info = null;
+        }
+        $json = memberships::get_users_json($this, $context, $lti->course, $tool, $role, $limitfrom, $limitnum, $lti, $info);
 
-            $response->set_content_type($this->formats[0]);
-            $response->set_body($json);
+        $response->set_content_type($this->formats[0]);
+        $response->set_body($json);
+    }
 
-        } catch (\Exception $e) {
-            $response->set_code($e->getCode());
+    /**
+     * get permissions from the config of the tool for that resource
+     *
+     * @param string $typeid
+     *
+     * @return array with the permissions related to this resource by the $lti_type or null if none.
+     */
+    public function get_permissions($typeid) {
+        $tool = lti_get_type_type_config($typeid);
+        if ($tool->memberships == '1') {
+            return array('ToolProxyBinding.memberships.url:get');
+        } else {
+            return array();
         }
-
     }
 
     /**
@@ -122,13 +146,14 @@ public function execute($response) {
      */
     public function parse_value($value) {
 
-        $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
-        if (!empty($id)) {
-            $cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);
-            $this->params['link_id'] = $cm->instance;
+        if (strpos($value, '$ToolProxyBinding.memberships.url') !== false) {
+            $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
+            if (!empty($id)) {
+                $cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);
+                $this->params['link_id'] = $cm->instance;
+            }
+            $value = str_replace('$LtiLink.memberships.url', parent::get_endpoint(), $value);
         }
-        $value = str_replace('$LtiLink.memberships.url', parent::get_endpoint(), $value);
-
         return $value;
 
     }
diff --git a/mod/lti/service/memberships/classes/local/service/memberships.php b/mod/lti/service/memberships/classes/local/service/memberships.php
index 8066d1be30ce1..ed6a0713ac44a 100644
--- a/mod/lti/service/memberships/classes/local/service/memberships.php
+++ b/mod/lti/service/memberships/classes/local/service/memberships.php
@@ -23,7 +23,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
-
 namespace ltiservice_memberships\local\service;
 
 defined('MOODLE_INTERNAL') || die();
@@ -46,6 +45,18 @@ class memberships extends \mod_lti\local\ltiservice\service_base {
     const CONTEXT_ROLE_LEARNER = 'http://purl.imsglobal.org/vocab/lis/v2/membership#Learner';
     /** Capability used to identify Instructors */
     const INSTRUCTOR_CAPABILITY = 'moodle/course:manageactivities';
+    /** Name of LTI service component */
+    const LTI_SERVICE_COMPONENT = 'ltiservice_memberships';
+    /** Membership services enabled */
+    const MEMBERSHIP_ENABLED = 1;
+    /** Always include field */
+    const ALWAYS_INCLUDE_FIELD = 1;
+    /** Allow the instructor to decide if included */
+    const DELEGATE_TO_INSTRUCTOR = 2;
+    /** Instructor chose to include field */
+    const INSTRUCTOR_INCLUDED = 1;
+    /** Instructor delegated and approved for include */
+    const INSTRUCTOR_DELEGATE_INCLUDED = array(self::DELEGATE_TO_INSTRUCTOR && self::INSTRUCTOR_INCLUDED);
 
     /**
      * Class constructor.
@@ -54,7 +65,7 @@ public function __construct() {
 
         parent::__construct();
         $this->id = 'memberships';
-        $this->name = get_string('servicename', 'ltiservice_memberships');
+        $this->name = get_string('servicename', self::LTI_SERVICE_COMPONENT);
 
     }
 
@@ -80,17 +91,18 @@ public function get_resources() {
      *
      * @param \mod_lti\local\ltiservice\resource_base $resource       Resource handling the request
      * @param \context_course   $context    Course context
-     * @param string            $id         Course ID
+     * @param string            $contextid  Course ID
      * @param object            $tool       Tool instance object
      * @param string            $role       User role requested (empty if none)
      * @param int               $limitfrom  Position of first record to be returned
      * @param int               $limitnum   Maximum number of records to be returned
      * @param object            $lti        LTI instance record
-     * @param info_module       $info       Conditional availability information for LTI instance (null if context-level request)
+     * @param \core_availability\info_module $info Conditional availability information
+     * for LTI instance (null if context-level request)
      *
-     * @return array
+     * @return string
      */
-    public static function get_users_json($resource, $context, $id, $tool, $role, $limitfrom, $limitnum, $lti, $info) {
+    public static function get_users_json($resource, $context, $contextid, $tool, $role, $limitfrom, $limitnum, $lti, $info) {
 
         $withcapability = '';
         $exclude = array();
@@ -110,10 +122,9 @@ public static function get_users_json($resource, $context, $id, $tool, $role, $l
             $limitfrom = 0;
             $limitnum = 0;
         }
-        $json = self::users_to_json($resource, $users, $id, $tool, $exclude, $limitfrom, $limitnum, $lti, $info);
+        $json = self::users_to_json($resource, $users, $contextid, $tool, $exclude, $limitfrom, $limitnum, $lti, $info);
 
         return $json;
-
     }
 
     /**
@@ -124,7 +135,7 @@ public static function get_users_json($resource, $context, $id, $tool, $role, $l
      *
      * @param \mod_lti\local\ltiservice\resource_base $resource       Resource handling the request
      * @param array  $users               Array of user records
-     * @param string $id                  Course ID
+     * @param string $contextid           Course ID
      * @param object $tool                Tool instance object
      * @param array  $exclude             Array of user records to be excluded from the response
      * @param int    $limitfrom           Position of first record to be returned
@@ -134,82 +145,197 @@ public static function get_users_json($resource, $context, $id, $tool, $role, $l
      *
      * @return string
      */
-    private static function users_to_json($resource, $users, $id, $tool, $exclude, $limitfrom, $limitnum,
-                                         $lti, $info) {
+    private static function users_to_json($resource, $users, $contextid, $tool, $exclude, $limitfrom, $limitnum,
+            $lti, $info) {
+        global $DB;
+
+        $arrusers = [
+            '@context' => 'http://purl.imsglobal.org/ctx/lis/v2/MembershipContainer',
+            '@type' => 'Page',
+            '@id' => $resource->get_endpoint(),
+        ];
 
-        $nextpage = 'null';
         if ($limitnum > 0) {
             $limitfrom += $limitnum;
-            $nextpage = "\"{$resource->get_endpoint()}?limit={$limitnum}&amp;from={$limitfrom}\"";
+            $nextpage = "{$resource->get_endpoint()}?limit={$limitnum}&from={$limitfrom}";
+            if (!is_null($lti)) {
+                $nextpage .= "&rlid={$lti->id}";
+            }
+            $arrusers['nextPage'] = $nextpage;
         }
-        $json = <<< EOD
-{
-  "@context" : "http://purl.imsglobal.org/ctx/lis/v2/MembershipContainer",
-  "@type" : "Page",
-  "@id" : "{$resource->get_endpoint()}",
-  "nextPage" : {$nextpage},
-  "pageOf" : {
-    "@type" : "LISMembershipContainer",
-    "membershipSubject" : {
-      "@type" : "Context",
-      "contextId" : "{$id}",
-      "membership" : [
-
-EOD;
+
+        $arrusers['pageOf'] = [
+            '@type' => 'LISMembershipContainer',
+            'membershipSubject' => [
+                '@type' => 'Context',
+                'contextId' => $contextid,
+                'membership' => []
+            ]
+        ];
+
         $enabledcapabilities = lti_get_enabled_capabilities($tool);
-        $sep = '        ';
+        $islti2 = $tool->toolproxyid > 0;
         foreach ($users as $user) {
-            $include = !in_array($user->id, $exclude);
-            if ($include && !empty($info)) {
-                $include = $info->is_user_visible($info->get_course_module(), $user->id);
+            if (in_array($user->id, $exclude)) {
+                continue;
             }
-            if ($include) {
-                $member = new \stdClass();
-                if (in_array('User.id', $enabledcapabilities)) {
-                    $member->userId = $user->id;
-                }
-                if (in_array('Person.sourcedId', $enabledcapabilities)) {
-                    $member->sourcedId = format_string($user->idnumber);
-                }
-                if (in_array('Person.name.full', $enabledcapabilities)) {
-                    $member->name = format_string("{$user->firstname} {$user->lastname}");
-                }
-                if (in_array('Person.name.given', $enabledcapabilities)) {
-                    $member->givenName = format_string($user->firstname);
-                }
-                if (in_array('Person.name.family', $enabledcapabilities)) {
-                    $member->familyName = format_string($user->lastname);
-                }
-                if (in_array('Person.email.primary', $enabledcapabilities)) {
-                    $member->email = format_string($user->email);
+            if (!empty($info) && !$info->is_user_visible($info->get_course_module(), $user->id)) {
+                continue;
+            }
+
+            $member = new \stdClass();
+            $member->{"@type" } = 'LISPerson';
+            $membership = new \stdClass();
+            $membership->status = 'Active';
+            $membership->role = explode(',', lti_get_ims_role($user->id, null, $contextid, true));
+
+            $toolconfig = lti_get_type_type_config($tool->id);
+            $instanceconfig = null;
+            if (!is_null($lti)) {
+                $instanceconfig = lti_get_type_config_from_instance($lti->id);
+            }
+            $isallowedlticonfig = self::is_allowed_field_set($toolconfig, $instanceconfig,
+                                    ['name' => 'lti_sendname', 'email' => 'lti_sendemailaddr']);
+
+            $includedcapabilities = [
+                'User.id'              => ['type' => 'id',
+                                            'member.field' => 'userId',
+                                            'source.value' => $user->id],
+                'Person.sourcedId'     => ['type' => 'id',
+                                            'member.field' => 'sourcedId',
+                                            'source.value' => format_string($user->idnumber)],
+                'Person.name.full'     => ['type' => 'name',
+                                            'member.field' => 'name',
+                                            'source.value' => format_string("{$user->firstname} {$user->lastname}")],
+                'Person.name.given'    => ['type' => 'name',
+                                            'member.field' => 'givenName',
+                                            'source.value' => format_string($user->firstname)],
+                'Person.name.family'   => ['type' => 'name',
+                                            'member.field' => 'familyName',
+                                            'source.value' => format_string($user->lastname)],
+                'Person.email.primary' => ['type' => 'email',
+                                            'member.field' => 'email',
+                                            'source.value' => format_string($user->email)]
+            ];
+
+            if (!is_null($lti)) {
+                $message = new \stdClass();
+                $message->message_type = 'basic-lti-launch-request';
+                $conditions = array('courseid' => $contextid, 'itemtype' => 'mod',
+                        'itemmodule' => 'lti', 'iteminstance' => $lti->id);
+
+                if (!empty($lti->servicesalt) && $DB->record_exists('grade_items', $conditions)) {
+                    $message->lis_result_sourcedid = json_encode(lti_build_sourcedid($lti->id,
+                                                                                     $user->id,
+                                                                                     $lti->servicesalt,
+                                                                                     $lti->typeid));
                 }
-                if (in_array('Result.sourcedId', $enabledcapabilities) && !empty($lti) && !empty($lti->servicesalt)) {
-                    $member->resultSourcedId = json_encode(lti_build_sourcedid($lti->id, $user->id, $lti->servicesalt,
-                                                           $lti->typeid));
+                $membership->message = $message;
+            }
+
+            foreach ($includedcapabilities as $capabilityname => $capability) {
+                if ($islti2) {
+                    if (!in_array($capabilityname, $enabledcapabilities)) {
+                        continue;
+                    }
+                } else {
+                    if (($capability['type'] === 'id')
+                     || ($capability['type'] === 'name' && $isallowedlticonfig['name'])
+                     || ($capability['type'] === 'email' && $isallowedlticonfig['email'])) {
+                        $member->{$capability['member.field']} = $capability['source.value'];
+                    }
                 }
-                $roles = explode(',', lti_get_ims_role($user->id, null, $id, true));
+            }
 
-                $membership = new \stdClass();
-                $membership->status = 'Active';
-                $membership->member = $member;
-                $membership->role = $roles;
+            $membership->member = $member;
 
-                $json .= $sep . json_encode($membership);
-                $sep = ",\n        ";
-            }
+            $arrusers['pageOf']['membershipSubject']['membership'][] = $membership;
+        }
 
+        return json_encode($arrusers);
+    }
+
+    /**
+     * Determines whether a user attribute may be used as part of LTI membership
+     * @param object            $toolconfig      Tool config
+     * @param object            $instanceconfig  Tool instance config
+     * @param array             $fields          Set of fields to return if allowed or not
+     * @return array Verification which associates an attribute with a boolean (allowed or not)
+     */
+    private static function is_allowed_field_set($toolconfig, $instanceconfig, $fields) {
+        $isallowedstate = [];
+        foreach ($fields as $key => $field) {
+            $allowed = self::ALWAYS_INCLUDE_FIELD == $toolconfig->{$field};
+            if (!$allowed) {
+                if (self::DELEGATE_TO_INSTRUCTOR == $toolconfig->{$field} && !is_null($instanceconfig)) {
+                    $allowed = $instanceconfig->{$field} == self::INSTRUCTOR_INCLUDED;
+                }
+            }
+            $isallowedstate[$key] = $allowed;
         }
+        return $isallowedstate;
+    }
 
-        $json .= <<< EOD
+    /**
+     * Adds form elements for membership add/edit page.
+     *
+     * @param \MoodleQuickForm $mform
+     */
+    public function get_configuration_options(&$mform) {
+        $elementname = 'ltiservice_memberships';
+        $options = [
+            get_string('notallow', self::LTI_SERVICE_COMPONENT),
+            get_string('allow', self::LTI_SERVICE_COMPONENT)
+        ];
 
-      ]
+        $mform->addElement('select', $elementname, get_string($elementname, self::LTI_SERVICE_COMPONENT), $options);
+        $mform->setType($elementname, 'int');
+        $mform->setDefault($elementname, 0);
+        $mform->addHelpButton($elementname, $elementname, self::LTI_SERVICE_COMPONENT);
     }
-  }
-}
-EOD;
 
-        return $json;
+    /**
+     * Return an array with the names of the parameters that the service will be saving in the configuration
+     *
+     * @return array with the names of the parameters that the service will be saving in the configuration
+     *
+     */
+    public function get_configuration_parameter_names() {
+        return array(self::LTI_SERVICE_COMPONENT);
+    }
+
+    /**
+     * Return an array of key/values to add to the launch parameters.
+     *
+     * @param string $messagetype 'basic-lti-launch-request' or 'ContentItemSelectionRequest'.
+     * @param string $courseid The course id.
+     * @param string $user The user id.
+     * @param string $typeid The tool lti type id.
+     * @param string $modlti The id of the lti activity.
+     *
+     * The type is passed to check the configuration
+     * and not return parameters for services not used.
+     *
+     * @return array of key/value pairs to add as launch parameters.
+     */
+    public function get_launch_parameters($messagetype, $courseid, $user, $typeid, $modlti = null) {
+        global $COURSE;
 
+        $launchparameters = array();
+        $tool = lti_get_type_type_config($typeid);
+        if (isset($tool->ltiservice_memberships)) {
+            if ($tool->ltiservice_memberships == '1' && $this->is_used_in_context($typeid, $courseid)) {
+                $endpoint = $this->get_service_path();
+                if ($COURSE->id === SITEID) {
+                    $contexttype = 'Group';
+                } else {
+                    $contexttype = 'CourseSection';
+                }
+                $launchparameters['custom_context_memberships_url'] = $endpoint .
+                    "/{$contexttype}/{$courseid}/bindings/{$typeid}/memberships";
+            }
+        }
+        return $launchparameters;
     }
 
 }
diff --git a/mod/lti/service/memberships/lang/en/ltiservice_memberships.php b/mod/lti/service/memberships/lang/en/ltiservice_memberships.php
index acb65d66a1e37..cd8d220dbe658 100644
--- a/mod/lti/service/memberships/lang/en/ltiservice_memberships.php
+++ b/mod/lti/service/memberships/lang/en/ltiservice_memberships.php
@@ -23,5 +23,9 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
+$string['allow'] = 'Use this service to retrieve members\' information as per privacy settings';
+$string['ltiservice_memberships'] = 'IMS LTI Membership: ';
+$string['ltiservice_memberships_help'] = 'Allow the tool to retrieve member\'s info from the course using the IMS LTI Membership Service. The privacy settings will apply.';
+$string['notallow'] = 'Do not use this service';
 $string['pluginname'] = 'Memberships LTI Service';
 $string['servicename'] = 'Memberships';
diff --git a/mod/lti/service/profile/classes/local/resources/profile.php b/mod/lti/service/profile/classes/local/resources/profile.php
index e636b29efdb26..bd55ac43b8b61 100644
--- a/mod/lti/service/profile/classes/local/resources/profile.php
+++ b/mod/lti/service/profile/classes/local/resources/profile.php
@@ -43,7 +43,7 @@ class profile extends \mod_lti\local\ltiservice\resource_base {
     /**
      * Class constructor.
      *
-     * @param ltiservice_profile\local\resources\profile $service Service instance
+     * @param service_base $service Service instance
      */
     public function __construct($service) {
 
@@ -76,10 +76,9 @@ public function get_path() {
     /**
      * Execute the request for this resource.
      *
-     * @param mod_lti\local\ltiservice\response $response  Response object for this request.
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
      */
     public function execute($response) {
-
         global $CFG;
 
         $version = service_base::LTI_VERSION2P0;
@@ -104,6 +103,7 @@ public function execute($response) {
             foreach ($services as $name => $location) {
                 if (in_array($name, $serviceofferedarr)) {
                     $classname = "\\ltiservice_{$name}\\local\\service\\{$name}";
+                    /** @var service_base $service */
                     $service = new $classname();
                     $service->set_tool_proxy($toolproxy);
                     $resources = $service->get_resources();
@@ -218,9 +218,9 @@ public function get_endpoint() {
      * @return string
      */
     public function parse_value($value) {
-
-        $value = str_replace('$ToolConsumerProfile.url', $this->get_endpoint(), $value);
-
+        if (strpos($value, '$ToolConsumerProfile.url') !== false) {
+            $value = str_replace('$ToolConsumerProfile.url', $this->get_endpoint(), $value);
+        }
         return $value;
 
     }
diff --git a/mod/lti/service/toolsettings/classes/local/resources/contextsettings.php b/mod/lti/service/toolsettings/classes/local/resources/contextsettings.php
index bbe9b2d47f342..e7c7b5c29afdf 100644
--- a/mod/lti/service/toolsettings/classes/local/resources/contextsettings.php
+++ b/mod/lti/service/toolsettings/classes/local/resources/contextsettings.php
@@ -26,7 +26,6 @@
 
 namespace ltiservice_toolsettings\local\resources;
 
-use ltiservice_toolsettings\local\resources\systemsettings;
 use ltiservice_toolsettings\local\service\toolsettings;
 
 defined('MOODLE_INTERNAL') || die();
@@ -44,7 +43,7 @@ class contextsettings extends \mod_lti\local\ltiservice\resource_base {
     /**
      * Class constructor.
      *
-     * @param ltiservice_toolsettings\local\resources\contextsettings $service Service instance
+     * @param \mod_lti\local\ltiservice\service_base $service Service instance
      */
     public function __construct($service) {
 
@@ -62,7 +61,7 @@ public function __construct($service) {
     /**
      * Execute the request for this resource.
      *
-     * @param mod_lti\local\ltiservice\response $response  Response object for this request.
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
      */
     public function execute($response) {
 
@@ -166,16 +165,17 @@ public function execute($response) {
     public function parse_value($value) {
         global $COURSE;
 
-        if ($COURSE->format == 'site') {
-            $this->params['context_type'] = 'Group';
-        } else {
-            $this->params['context_type'] = 'CourseSection';
+        if (strpos($value, '$ToolProxyBinding.custom.url') !== false) {
+            if ($COURSE->format == 'site') {
+                $this->params['context_type'] = 'Group';
+            } else {
+                $this->params['context_type'] = 'CourseSection';
+            }
+            $this->params['context_id'] = $COURSE->id;
+            $this->params['vendor_code'] = $this->get_service()->get_tool_proxy()->vendorcode;
+            $this->params['product_code'] = $this->get_service()->get_tool_proxy()->guid;
+            $value = str_replace('$ToolProxyBinding.custom.url', parent::get_endpoint(), $value);
         }
-        $this->params['context_id'] = $COURSE->id;
-        $this->params['vendor_code'] = $this->get_service()->get_tool_proxy()->vendorcode;
-        $this->params['product_code'] = $this->get_service()->get_tool_proxy()->guid;
-        $value = str_replace('$ToolProxyBinding.custom.url', parent::get_endpoint(), $value);
-
         return $value;
 
     }
diff --git a/mod/lti/service/toolsettings/classes/local/resources/linksettings.php b/mod/lti/service/toolsettings/classes/local/resources/linksettings.php
index 595dd576d503e..2c7700620740f 100644
--- a/mod/lti/service/toolsettings/classes/local/resources/linksettings.php
+++ b/mod/lti/service/toolsettings/classes/local/resources/linksettings.php
@@ -23,11 +23,8 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
-
 namespace ltiservice_toolsettings\local\resources;
 
-use ltiservice_toolsettings\local\resources\systemsettings;
-use ltiservice_toolsettings\local\resources\contextsettings;
 use ltiservice_toolsettings\local\service\toolsettings;
 
 defined('MOODLE_INTERNAL') || die();
@@ -45,7 +42,7 @@ class linksettings extends \mod_lti\local\ltiservice\resource_base {
     /**
      * Class constructor.
      *
-     * @param ltiservice_toolsettings\local\resources\linksettings $service Service instance
+     * @param \mod_lti\local\ltiservice\service_base $service Service instance
      */
     public function __construct($service) {
 
@@ -63,7 +60,7 @@ public function __construct($service) {
     /**
      * Execute the request for this resource.
      *
-     * @param mod_lti\local\ltiservice\response $response  Response object for this request.
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
      */
     public function execute($response) {
         global $DB, $COURSE;
@@ -82,6 +79,7 @@ public function execute($response) {
 
         $systemsetting = null;
         $contextsetting = null;
+        $lti = null;
         if ($ok) {
             $ok = !empty($linkid);
             if ($ok) {
@@ -195,13 +193,14 @@ public function execute($response) {
      */
     public function parse_value($value) {
 
-        $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
-        if (!empty($id)) {
-            $cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);
-            $this->params['link_id'] = $cm->instance;
+        if (strpos($value, '$LtiLink.custom.url') !== false) {
+            $id = optional_param('id', 0, PARAM_INT); // Course Module ID.
+            if (!empty($id)) {
+                $cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);
+                $this->params['link_id'] = $cm->instance;
+            }
+            $value = str_replace('$LtiLink.custom.url', parent::get_endpoint(), $value);
         }
-        $value = str_replace('$LtiLink.custom.url', parent::get_endpoint(), $value);
-
         return $value;
 
     }
diff --git a/mod/lti/service/toolsettings/classes/local/resources/systemsettings.php b/mod/lti/service/toolsettings/classes/local/resources/systemsettings.php
index 28268413565ef..b6be719216ad4 100644
--- a/mod/lti/service/toolsettings/classes/local/resources/systemsettings.php
+++ b/mod/lti/service/toolsettings/classes/local/resources/systemsettings.php
@@ -27,6 +27,7 @@
 namespace ltiservice_toolsettings\local\resources;
 
 use ltiservice_toolsettings\local\service\toolsettings;
+use mod_lti\local\ltiservice\resource_base;
 
 defined('MOODLE_INTERNAL') || die();
 
@@ -38,12 +39,12 @@
  * @copyright  2014 Vital Source Technologies http://vitalsource.com
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class systemsettings extends \mod_lti\local\ltiservice\resource_base {
+class systemsettings extends resource_base {
 
     /**
      * Class constructor.
      *
-     * @param ltiservice_toolsettings\local\service\toolsettings $service Service instance
+     * @param \mod_lti\local\ltiservice\service_base $service Service instance
      */
     public function __construct($service) {
 
@@ -61,7 +62,7 @@ public function __construct($service) {
     /**
      * Execute the request for this resource.
      *
-     * @param mod_lti\local\ltiservice\response $response  Response object for this request.
+     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.
      */
     public function execute($response) {
 
@@ -143,9 +144,9 @@ public function execute($response) {
      * @return string
      */
     public function parse_value($value) {
-
-        $value = str_replace('$ToolProxy.custom.url', parent::get_endpoint(), $value);
-
+        if (strpos($value, '$ToolProxy.custom.url') !== false) {
+            $value = str_replace('$ToolProxy.custom.url', parent::get_endpoint(), $value);
+        }
         return $value;
 
     }