Hi, I'm a developer who has an app that does a variety of things including grade passback using LTI Advantage. After a few thousand successful grade passbacks, my calls began to fail for a small subset of students from one school. I thought this was odd since I was using the same exact code for all students in the school. After connecting with the school's Canvas Admin, they eventually got Instructure involved and after going through a Level 1 and then finally a Level 2 engineer, they were able to determine the issue. Regardless of the specifics, from the first email until a solution was presented, approximately 6 weeks passed. My question is whether Instructure offers any paid support for developers so that I might be able to receive quicker feedback. And, if so, has anyone here has used that support more successfully than the forum? ... View more

Hi, I've been using LTI 1.3 to passback grades successfully from my application to Canvas and have just encountered something a bit odd.  As the title suggests, I'm getting "Invalid access token field/s: the 'aud' is invalid" but this is only for a single student at the university.  They all have the same *.edu email.  Any thoughts would be appreciated. Thank you,   Eric ... View more

Hi, As part of LTI 1.3, "person_sourcedid" is passed back. For actual schools, can this be a trusted value for a student's school user id?  Or, is this something that an LMS may or may not pass back?  For example, this value is null in my dev instance but this makes sense to me since I don't actually have a student id. Thanks so much, Eric ... View more

Hi, I've (finally) gotten my app to use LTI Advantage in order to pass back grades.  After each launch, Canvas sends back a JWT with my library uses to passback the score.  I'm currently saving the JWT in my database and using it until another launch and then saving the "updated" JWT to use for the subsequent grade passback.  I  put updated in quotes since I'm unsure whether this will ever change for a given user-assignment.  In other words, can I save the JWT from the initial launch and then just re-use in order to pass back the grades? Thanks so much,   Eric ... View more

Hi, I think (?) I'm following the documentation in creating custom fields for an LTI 1.3 app: { "title": "Adapt", "scopes": [ "https://purl.imsglobal.org/spec/lti-ags/scope/lineitem", "https://purl.imsglobal.org/spec/lti-ags/scope/lineitem.readonly", "https://purl.imsglobal.org/spec/lti-ags/scope/result.readonly", "https://purl.imsglobal.org/spec/lti-ags/scope/score", "https://purl.imsglobal.org/spec/lti-nrps/scope/contextmembership.readonly" ], "extensions": [ { "platform": "canvas.instructure.com", "settings": { "platform": "canvas.instructure.com", "placements": [ { "placement": "link_selection", "message_type": "LtiDeepLinkingRequest", "target_link_uri": "https://dev.adapt.libretexts.org/api/lti/configure" }, { "placement": "assignment_selection", "message_type": "LtiDeepLinkingRequest", "target_link_uri": "https://dev.adapt.libretexts.org/api/lti/configure" } ], "link_selection": { "placement": "link_selection", "message_type": "LtiDeepLinkingRequest", "target_link_uri": "https://dev.adapt.libretexts.org/api/lti/configure" }, "assignment_selection": { "placement": "assignment_selection", "message_type": "LtiDeepLinkingRequest", "target_link_uri": "https://dev.adapt.libretexts.org/api/lti/configure" } } } ], "public_jwk": { ~an actual key~ }, "description": "Adapt-2", "custom_fields": { "custom_canvas_api_domain": "$Canvas.api.domain", "custom_canvas_course_id": "$Canvas.course.id", "custom_canvas_user_id": "$Canvas.user.id", "user_image": "$User.image", "membership_roles": "$Canvas.membership.roles", "custom_canvas_account_id": "$Canvas.account.id", "custom_canvas_user_is_root_account_admin": "$Canvas.user.isRootAccountAdmin", "custom_canvas_root_account_id": "$Canvas.rootAccount.id", "custom_canvas_root_account_uuid": "$vnd.Canvas.root_account.uuid", "account_name": "$Canvas.account.name", "custom_external_tool_url": "$Canvas.externalTool.url" }, "target_link_uri": "https://dev.adapt.libretexts.org/api/lti/redirect-uri", "oidc_initiation_url": "https://dev.adapt.libretexts.org/api/lti/oidc-initiation-url" }  However, upon launching,  https://purl.imsglobal.org/spec/lti/claim/custom returns an empty array:   -jwt: array:2 [▼ "header" => array:3 [▶] "body" => array:27 [▼ "https://purl.imsglobal.org/spec/lti/claim/message_type" => "LtiResourceLinkRequest" "https://purl.imsglobal.org/spec/lti/claim/version" => "1.3.0" "https://purl.imsglobal.org/spec/lti/claim/resource_link" => array:5 [▶] "https://purl.imsglobal.org/spec/lti-ags/claim/endpoint" => array:5 [▶] "aud" => "10000000000028" "azp" => "10000000000028" "https://purl.imsglobal.org/spec/lti/claim/deployment_id" => "32:20d4c62c24a96e1f3afb75776a253004109a1e22" "exp" => 1629122455 "iat" => 1629118855 "iss" => "https://dev-canvas.libretexts.org" "nonce" => "nonce-611a6188f00478.76082033" "sub" => "382a91b9-a622-45fa-96be-966647be198f" "https://purl.imsglobal.org/spec/lti/claim/target_link_uri" => "https://dev.adapt.libretexts.org/api/lti/redirect-uri" "picture" => "https://dev-canvas.libretexts.org/images/messages/avatar-50.png" "email" => "me@me.org" "name" => "me@me.org" "given_name" => "Me" "family_name" => "" "https://purl.imsglobal.org/spec/lti/claim/lis" => array:4 [▶] "https://purl.imsglobal.org/spec/lti/claim/context" => array:6 [▶] "https://purl.imsglobal.org/spec/lti/claim/tool_platform" => array:6 [▶] "https://purl.imsglobal.org/spec/lti/claim/launch_presentation" => array:7 [▶] "locale" => "en" "https://purl.imsglobal.org/spec/lti/claim/roles" => array:6 [▶] "https://purl.imsglobal.org/spec/lti/claim/custom" => [] "errors" => array:1 [▶] "https://purl.imsglobal.org/spec/lti-nrps/claim/namesroleservice" => array:4 [▶]   Any help would be greatly appreciated. ... View more