MDL-39087 Add new helper methods to the plugin_manager API

These are mainly intended for callers that had to iterate over
get_plugins() result manually.

admin/courseformats.php

@@ -40,8 +40,7 @@
 
 $return = new moodle_url('/admin/settings.php', array('section' => 'manageformats'));
 
-$allplugins = plugin_manager::instance()->get_plugins();
-$formatplugins = $allplugins['format'];
+$formatplugins = plugin_manager::instance()->get_plugins_of_type('format');
 $sortorder = array_flip(array_keys($formatplugins));
 
 if (!isset($formatplugins[$formatname])) {

lib/adminlib.php

@@ -6071,8 +6071,7 @@ public function is_related($query) {
         if (parent::is_related($query)) {
             return true;
         }
-        $allplugins = plugin_manager::instance()->get_plugins();
-        $formats = $allplugins['format'];
+        $formats = plugin_manager::instance()->get_plugins_of_type('format');
         foreach ($formats as $format) {
             if (strpos($format->component, $query) !== false ||
                     strpos(textlib::strtolower($format->displayname), $query) !== false) {
@@ -6095,8 +6094,7 @@ public function output_html($data, $query='') {
         $return = $OUTPUT->heading(new lang_string('courseformats'), 3, 'main');
         $return .= $OUTPUT->box_start('generalbox formatsui');
 
-        $allplugins = plugin_manager::instance()->get_plugins();
-        $formats = $allplugins['format'];
+        $formats = plugin_manager::instance()->get_plugins_of_type('format');
 
         // display strings
         $txt = get_strings(array('settings', 'name', 'enable', 'disable', 'up', 'down', 'default', 'delete'));

lib/editor/tinymce/settings.php

@@ -48,8 +48,7 @@
 unset($settings);
 
 require_once("$CFG->libdir/pluginlib.php");
-$allplugins = plugin_manager::instance()->get_plugins();
-foreach ($allplugins['tinymce'] as $plugin) {
+foreach (plugin_manager::instance()->get_plugins_of_type('tinymce') as $plugin) {
     $plugin->load_settings($ADMIN, 'editortinymce', $hassiteconfig);
 }
 

lib/pluginlib.php

@@ -107,6 +107,27 @@ public function get_plugin_types($fullpaths = true) {
         return $this->reorder_plugin_types(get_plugin_types($fullpaths));
     }
 
+    /**
+     * Returns list of known plugins of the given type
+     *
+     * This method returns the subset of the tree returned by {@link self::get_plugins()}.
+     * If the given type is not known, empty array is returned.
+     *
+     * @param string $type plugin type, e.g. 'mod' or 'workshopallocation'
+     * @param bool $disablecache force reload, cache can be used otherwise
+     * @return array (string)plugin name (e.g. 'workshop') => corresponding subclass of {@link plugininfo_base}
+     */
+    public function get_plugins_of_type($type, $disablecache=false) {
+
+        $plugins = $this->get_plugins($disablecache);
+
+        if (!isset($plugins[$type])) {
+            return array();
+        }
+
+        return $plugins[$type];
+    }
+
     /**
      * Returns a tree of known plugins and information about them
      *
@@ -161,6 +182,41 @@ public function get_plugins($disablecache=false) {
         return $this->pluginsinfo;
     }
 
+    /**
+     * Returns list of all known subplugins of the given plugin
+     *
+     * For plugins that do not provide subplugins (i.e. there is no support for it),
+     * empty array is returned.
+     *
+     * @param string $component full component name, e.g. 'mod_workshop'
+     * @param bool $disablecache force reload, cache can be used otherwise
+     * @return array (string) component name (e.g. 'workshopallocation_random') => subclass of {@link plugininfo_base}
+     */
+    public function get_subplugins_of_plugin($component, $disablecache=false) {
+
+        $pluginfo = $this->get_plugin_info($component, $disablecache);
+
+        if (is_null($pluginfo)) {
+            return array();
+        }
+
+        $subplugins = $this->get_subplugins($disablecache);
+
+        if (!isset($subplugins[$pluginfo->component])) {
+            return array();
+        }
+
+        $list = array();
+
+        foreach ($subplugins[$pluginfo->component] as $subdata) {
+            foreach ($this->get_plugins_of_type($subdata->type) as $subpluginfo) {
+                $list[$subpluginfo->component] = $subpluginfo;
+            }
+        }
+
+        return $list;
+    }
+
     /**
      * Returns list of plugins that define their subplugins and the information
      * about them from the db/subplugins.php file.
@@ -294,12 +350,15 @@ public function plugintype_name_plural($type) {
     }
 
     /**
+     * Returns information about the known plugin, or null
+     *
      * @param string $component frankenstyle component name.
+     * @param bool $disablecache force reload, cache can be used otherwise
      * @return plugininfo_base|null the corresponding plugin information.
      */
-    public function get_plugin_info($component) {
+    public function get_plugin_info($component, $disablecache=false) {
         list($type, $name) = $this->normalize_component($component);
-        $plugins = $this->get_plugins();
+        $plugins = $this->get_plugins($disablecache);
         if (isset($plugins[$type][$name])) {
             return $plugins[$type][$name];
         } else {

lib/tests/pluginlib_test.php

@@ -49,9 +49,24 @@ public function test_plugin_manager_instance() {
         $this->assertTrue($pluginman instanceof testable_plugin_manager);
     }
 
+    public function test_get_plugins_of_type() {
+        $pluginman = testable_plugin_manager::instance();
+        $mods = $pluginman->get_plugins_of_type('mod');
+        $this->assertEquals('array', gettype($mods));
+        $this->assertEquals(2, count($mods));
+        $this->assertTrue($mods['foo'] instanceof testable_plugininfo_mod);
+        $this->assertTrue($mods['bar'] instanceof testable_plugininfo_mod);
+        $foolishes = $pluginman->get_plugins_of_type('foolish');
+        $this->assertEquals(1, count($foolishes));
+        $this->assertTrue($foolishes['frog'] instanceof testable_pluginfo_foolish);
+        $unknown = $pluginman->get_plugins_of_type('muhehe');
+        $this->assertSame(array(), $unknown);
+    }
+
     public function test_get_plugins() {
         $pluginman = testable_plugin_manager::instance();
         $plugins = $pluginman->get_plugins();
+        $this->assertEquals('array', gettype($plugins));
         $this->assertTrue(isset($plugins['mod']['foo']));
         $this->assertTrue(isset($plugins['mod']['bar']));
         $this->assertTrue(isset($plugins['foolish']['frog']));
@@ -60,6 +75,16 @@ public function test_get_plugins() {
         $this->assertTrue($plugins['foolish']['frog'] instanceof testable_pluginfo_foolish);
     }
 
+    public function test_get_subplugins_of_plugin() {
+        $pluginman = testable_plugin_manager::instance();
+        $this->assertSame(array(), $pluginman->get_subplugins_of_plugin('mod_missing'));
+        $this->assertSame(array(), $pluginman->get_subplugins_of_plugin('mod_bar'));
+        $foosubs = $pluginman->get_subplugins_of_plugin('mod_foo');
+        $this->assertEquals('array', gettype($foosubs));
+        $this->assertEquals(1, count($foosubs));
+        $this->assertTrue($foosubs['foolish_frog'] instanceof testable_pluginfo_foolish);
+    }
+
     public function test_get_subplugins() {
         $pluginman = testable_plugin_manager::instance();
         $subplugins = $pluginman->get_subplugins();

lib/upgrade.txt

@@ -51,6 +51,8 @@ information provided here is intended especially for developers.
 * Additional (optional) param $onlyactive has been added to get_enrolled_users, count_enrolled_users
   functions to get information for only active (excluding suspended enrolments) users. Included two
   helper functions extract_suspended_users, get_suspended_userids to extract suspended user information.
+* The plugin_manager class now provides two new helper methods for getting information
+  about known plugins: get_plugins_of_type() and get_subplugins_of_plugin().
 
 Database (DML) layer:
 * $DB->sql_empty() is deprecated, you have to use sql parameters with empty values instead,