Demo LTI 1.3 Tool

This is a small LTI 1.3 tool that can be installed.

Create config directory

To run the Spring Boot application, we need to have a bean of type:

org.springframework.security.oauth2.client.registration.ClientRegistrationRepository

Hence, we need to create a config folder in the root directory and inside that we need to add an application.properties file.

TLS Setup

To setup TLS in a development environment it's recommended that you install mkcert which will install a trusted root certificate and then allow a certificate to be generated for localhost. Once installed run this in the root of the project:

mkcert -pkcs12 -p12-file config/keystore.p12 localhost

Then start the application with the ssl profile enabled and the LTI tool should be accessible on https://localhost:8443/

LTI 1.3 Setup

For LTI 1.3 a public/private keypair is needed. To generate one for development use:

keytool -genkeypair \
  -alias jwt \
  -keyalg RSA \
  -keystore config/jwk.jks \
  -storepass store-pass \
  -dname CN=development

Setup in Canvas

Go to you account and add a LTI Developer Key, fill in the following:

• Key name: Name of your tool's key (eg LTI 1.3 Tool Key)
• Owner email: your email.
• Redirect URIs: https://server/lti/login
• Method: Paste JSON
• LTI 1.3 Configuration: Go to https://server/config.json and copy and paste the content into this field.

Local Canvas Setup

Open the file config/application.properties and add these properties or copy config/application-example.properties:

spring.security.oauth2.client.registration.canvas.client-id=1234
spring.security.oauth2.client.registration.canvas.client-secret=secret
spring.security.oauth2.client.registration.canvas.authorization-grant-type=implicit
spring.security.oauth2.client.registration.canvas.scope=openid
spring.security.oauth2.client.registration.canvas.redirect-uri={baseUrl}/lti/login

spring.security.oauth2.client.provider.canvas.authorization-uri=https://canvas.instructure.com/api/lti/authorize_redirect
spring.security.oauth2.client.provider.canvas.token-uri=https://canvas.instructure.com/login/oauth2/token
spring.security.oauth2.client.provider.canvas.jwk-set-uri=https://canvas.instructure.com/api/lti/security/jwks
spring.security.oauth2.client.provider.canvas.user-name-attribute=sub

• replace the client-id value (1234) with the ID of the LTI Developer Key you have created.
• you can update the URIs to point to the canvas instance you are using, but it works fine using the canvas.instructure.com

LTI Reference Implementation Setup

There is a reference implementation for testing LTI integrations available at https://lti-ri.imsglobal.org which allows you to create a Platform to perform test launches with. These instructions assume you are running the tool on https://localhost:8443/

Step 1: Generate public / private key pair for platform

• Open Generate Keys in a new tab and keep this tab open.

Step 2: Create a Platform (LMS)

• Open Manage Platforms in a new tab
• Click Add Platform.
• Add a unique name for your Platform.
• Provide a OAuth2 client id. (ex: 12345)
• Add a audience (ex: https://lti-ri.imsglobal.org)
• Set Tool Deep Link Service Endpoint to https://localhost:8443/
• Copy Public key from Generate Keys tab and paste into Platform Public Key field
• Copy Private key from Generate Keys tab and paste into Platform Private Key field
• Run keytool -list -rfc -keystore config/jwk.jks -alias jwt -storepass store-pass at the root of the project and copy the certificate into to Tool Public Key field.
• Click Save

Step 3: Add Deployment to Platform

• Find your Platform in the list of Platforms
• View your Platform
• Click Platform Keys
• Click Add Platform Key.
• Create a name for your Platform Key (ex: Key 1)
• Add Deployment ID (ex: 1, you may set up multiple later)
• Click Save

Step 4: Configure our tool

• Add a oauth registration/provider for the LTI RI platform to config/application.properties:

  spring.security.oauth2.client.registration.ims-ri.client-id=oauth-12345
  spring.security.oauth2.client.registration.ims-ri.client-secret=unused
  spring.security.oauth2.client.registration.ims-ri.authorization-grant-type=implicit
  spring.security.oauth2.client.registration.ims-ri.scope=openid
  spring.security.oauth2.client.registration.ims-ri.redirect-uri={baseUrl}/lti/login
  
  spring.security.oauth2.client.provider.ims-ri.authorization-uri=https://lti-ri.imsglobal.org/platforms/343/authorizations/new
  spring.security.oauth2.client.provider.ims-ri.token-uri=https://lti-ri.imsglobal.org/platforms/343/access_tokens
  spring.security.oauth2.client.provider.ims-ri.jwk-set-uri=https://lti-ri.imsglobal.org/platforms/343/platform_keys/333.json
  spring.security.oauth2.client.provider.ims-ri.user-name-attribute=sub
  

• Update OAuth2 client id (spring.security.oauth2.client.registration.ims-ri.client-id), same value as Platform above (ex: 12345)

• In Platform tab, navigate to your platform

• Click View Platform

• Click Platform Keys

• Copy well-known/jwks URL endpoint

• Update JWT URI (spring.security.oauth2.client.provider.ims-ri.jwk-set-uri) with the copied value.

• In Platform tab, navigate to your platform

• Copy the OAuth2 Access Token URL value

• Update Token URI (spring.security.oauth2.client.provider.ims-ri.token-uri) with the copied value.

• Copy the OIDC Auth URL from Platform Page

• Update Authorization URI (spring.security.oauth2.client.provider.ims-ri.authorization-uri) with the copied value.

Step 5: In Platform tab, view your Platform

• Click Courses

• Click Add Course

• Populate course values in form

• Click save

• Navigate back and view your Platform

• Click Resource Links

• Populate resource link values in form

• For Tool link url, use https://localhost:8443/

• For Login initiation url, use https://localhost:8443/lti/login_initiation/ims-ri

• Click Save

• Navigate and view your Platform

• Click Resource Links

• Click Select User for Launch

• Click on Launch Resource Link (OIDC) for a user

• Click on Post request

• Click on Launch Resource Link

• Click on Perform Launch

• If configuration is setup correctly, you should see Successful Launch at top of page