LMS Canvas LTI Framework Services

When this library is added to a project it allows for LTI framework service details to be setup.

Installation

From Maven

Add the following as a dependency in your pom.xml

<dependency>
    <groupId>edu.iu.uits.lms</groupId>
    <artifactId>lms-canvas-lti-framework</artifactId>
    <version><!-- latest version --></version>
</dependency>

You can find the latest version in Maven Central.

Setup Examples

Include annotation to enable to the configs

Add to any configuration class, or even the main application class @EnableLtiClient(toolKeys = {"example_tool_id"}).

Replace example_tool_id with something that will uniquely identify your tool. Once that has been done, you can autowire in and use any lti service. Generally, you won't use them directly, but they are used in various configurations.

Override default role mappings

Implement a class, similar to the below

public class CustomRoleMapper extends LmsDefaultGrantedAuthoritiesMapper {
   @Override
   protected List<String> getDefaultInstructorRoles() {
      return Arrays.asList("special", "roles", "here");
   }
}

Then, just use that when configuring...

Lti13Configurer lti13Configurer = new Lti13Configurer()
      .grantedAuthoritiesMapper(new CustomRoleMapper());

Setup Database

After compiling, see target/generated-resources/sql/ddl/auto/postgresql9.sql for appropriate ddl. Insert a record into the LTI_13_AUTHZ table with your tool's registration_id (example_tool_id, from above), along with the client_id and secret from Canvas's Developer Key. An env designator is also required here, and allows a database to support multiple environments simultaneously (dev and reg, for example).

Configuration

If choosing to use properties files for the configuration values, the default location is /usr/src/app/config, but that can be overridden by setting the app.fullFilePath value via system property or environment variable.

Database Configuration

The following properties need to be set to configure the communication with a database. They can be set in a security.properties file, or overridden as environment variables.

Property	Description
lms.db.user	Username used to access the database
lms.db.url	JDBC URL of the database. Will have the form jdbc:<dbtype>://<host>:<port>/<database>
lms.db.password	Password for the user accessing the database
lms.db.poolType	Fully qualified name of the connection pool implementation to use. By default, it is auto-detected from the classpath.

Configure support contact information

The following properties need to be set to configure the contact information on the global error page. They can be set in a security.properties file, or overridden as environment variables.

Property	Description
lti.errorcontact.name	Display name for your support organization
lti.errorcontact.link	Contact mechanism - URL or mailto:email (e.g. http://support.school.edu or mailto:support@school.edu)

Exposing the LTI authz REST endpoints

If you would like to expose the LTI authz endpoints in a tool (for CRUD operations on the LTI authorizations), you will need to enable it by including the value ltirest into the SPRING_PROFILES_ACTIVE environment variable. Be aware that if the tool requires multiple values, that there could be more than one profile value in there.

OAuth2 requirements

In order to get access to the endpoints, you'd need to configure an OAuth2 server. Once setup, the user(s) needing access would have to be granted the lti:read and/or the lti:write scopes as appropriate. Grant type should be set as Authorization Code.

REST endpoint documentation

See the wiki for details.

Dev notes

To generate the REST docs (asciidoc) that live in the github wiki, take the following steps:

1. Enable the rest endpoints and swagger in the tool of choice and start it up
2. Note the api docs url. Should be something like http://localhost:8080/api/lti/v3/api-docs
3. Download the openapi-generator from here
4. Run the following (:warning: Command could be slightly different based on your OS and install method): openapi-generator generate -g asciidoc -i <url_from_above_step>
5. Take the generated output and update the wiki page (:warning: Some hand editing may be required)