Testing with the IMS Reference Implementation

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The IMS LTI Reference Implementation provides a free test platform you can launch from without needing access to Canvas, Moodle, or Blackboard. This guide covers setting it up with the tool you built with Ltix.

Before starting, complete the Getting Started guide so you have a running tool with routes, a controller, and a storage adapter.

Create a platform

  1. Go to Manage Platforms and click Add Platform
  2. Fill in a name, client ID (e.g. my-tool), and audience
  3. Generate keys at Generate Keys and paste the public and private keys into the platform form
  4. Save the platform

Add a deployment

  1. View your platform and click Platform Keys
  2. Click Add Platform Key, give it a name and a deployment ID (e.g. 1)
  3. Save and note the well-known/jwks URL on this page

Configure your storage adapter

Copy the values from the RI platform page into your storage adapter. You need the following fields.

RI Platform fieldStorage field
Issuer (shown on platform page)Registration :issuer
Client ID (what you entered)Registration :client_id
OIDC Auth URLRegistration :auth_endpoint
well-known/jwks URL (from Platform Keys)Registration :jwks_uri
Deployment ID (from Platform Keys)Deployment :deployment_id
  1. View your platform and click Resource Links
  2. Fill in the form with these values.
    • Tool link url - https://localhost:4000/lti/launch
    • Login initiation url - https://localhost:4000/lti/login
  3. Save

Add a course

  1. View your platform and click Courses
  2. Fill in a course name and save

Launch

  1. View your platform and click Resource Links
  2. Click Select User for Launch, then Launch with New User
  3. Scroll down and click Perform Launch

If everything is configured correctly, you'll see your launch page with the parsed launch data (user info, roles, context, and resource link).

Troubleshooting

If the launch fails without an error, check these common issues.

  • Self-signed certificate not accepted. Visit https://localhost:4000 in your browser and accept the certificate warning before attempting a launch. Otherwise the platform's redirect will fail without an error.
  • Session cookie not sent. Make sure your endpoint uses same_site: "None", secure: true, and extra: "Partitioned". See Getting Started for details.
  • Mismatched issuer or client_id. Double-check that the values in your storage adapter match the RI platform page exactly.

Known limitations of the reference implementation

The IMS Reference Implementation is useful for verifying a basic launch, but it has significant bugs and gaps beyond that. Service endpoints (AGS, NRPS) may return non-compliant responses, behave inconsistently, or fail. Treat it as a smoke test for the OIDC login flow. For thorough testing of Advantage Services, use a real LMS like Canvas or Moodle. Even their sandbox environments will give you far more reliable results.