TICKET-583: Include due date in LTI gradebook sync

[Naragod]

Proposed Changes 🐛 Bug fix

When creating or updating a gradebook item via LTI, MarkUs sends a line item payload to Canvas containing the assignment label, resource ID, and maximum score. The dueAt field supported by the LTI Assignment and Grade Services (AGS) specification was missing from this payload, and the due date set in MarkUs remained absent on the corresponding Canvas assignment. The fix adds dueAt as an ISO 8601 timestamp to the payload when the assessment has a due date, ensuring it is synced during both line item creation and updates.

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[coveralls]

Coverage Report for CI Build 24734649524

Coverage increased (+0.001%) to 91.714%

Details

• Coverage increased (+0.001%) from the base build.
• Patch coverage: 7 of 7 lines across 2 files are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	48568
Covered Lines:	45285
Line Coverage:	93.24%
Relevant Branches:	1854
Covered Branches:	959
Branch Coverage:	51.73%
Branches in Coverage %:	Yes
Coverage Strength:	130.73 hits per line

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💛 - Coveralls

[donny-wong]

Thanks for this. However, when I tested it locally, the due date was still not syncing to Canvas. Are you able to sync on your end?

[Naragod]

Thanks for this. However, when I tested it locally, the due date was still not syncing to Canvas. Are you able to sync on your end?

Hi Donny, I have updated PR and posted a screenshot.