Integrating Opencast using LTI

About LTI

LTI provides an easy way to integrate Opencast into any system which can act as an LTI tool consumer such as many learning management systems (LMS). Popular examples for LTI consumers include Sakai, Moodle or ILIAS.

Using the LTI integration, students can access Opencast through an LTI tool in the LMS course site, and can play back Opencast videos without ever leaving their course.

More information about the LTI specification is available at IMS Learning Tools Interoperability.

Configuration

Configure OAuth

LTI uses OAuth to authenticate users. To enable OAuth in Opencast, edit etc/security/mh_default_org.xml and uncomment the oauthProtectedResourceFilter in the authentication filters section:

<ref bean="oauthProtectedResourceFilter" />

Next, configure the OAuth consumer by setting custom credentials in etc/org.opencastproject.kernel.security.OAuthConsumerDetailsService.cfg:

oauth.consumer.name.1=CONSUMERNAME
oauth.consumer.key.1=CONSUMERKEY
oauth.consumer.secret.1=CONSUMERSECRET

Configure LTI

Opencast's LTI module allows additional configuration like making a OAuth consumer key a highly trusted key, preventing Opencast from generating a temporary username, or to block some specific usernames like the system administrator.

For more details, take a look at the options in etc/org.opencastproject.kernel.security.LtiLaunchAuthenticationHandler.cfg.

Configure and test an LTI tool in the LMS

Configure an LTI tool in the LMS with these values:

Access the LTI tool configured for Opencast in the LMS. The Opencast LTI welcome page should appear. Use the links provided there to verify the LTI connection.

LTI Roles

LTI users will only see Opencast series and videos which are public, or those to which they have access because of the Opencast roles which they have. The Opencast LTI module grants an LTI user the role(s) formed from the LTI parameters context_id and roles.

The LTI context is typically the LMS course ID, and the default LTI role for a student in a course is Learner. The Opencast role granted would therefore be SITEID_Learner.

To make a series or video visible to students who access Opencast through LTI in an LMS course, add the role SITEID_Learner to the Series or Event Access Control List (ACL).

LTI users may also have additional roles if the LTI user is created as an Opencast user in the Admin UI and given additional roles, or if one or more Opencast User Providers or Role Providers are configured.

Specifying LTI Tools

Opencast will redirect an LTI user to the URL specified by the LTI custom tool parameter. Some LMS systems allow custom parameters to be defined separately in each place where an LTI tool is used, whereas other systems only allow custom parameters to be defined globally.

For more information about how to set custom LTI parameters, please check the documentation of your LMS.

Series LTI Tool

Opencast's series LTI tool provides the option to provide custom style sheets for configuring the look and feel of the tool which may be important to match the design of the LTI consumer in which it is included. The CSS file can be found in the user interface configuration directory usually located at:

etc/ui-config/mh_default_org/ltitools/series.css