instructure/canvas-lms · error · GraphQL::ExecutionError

Assignment not found

Error message

Assignment not found

What it means

Raised by get_assignment in AllocationRuleBase when Assignment.active.find(assignment_id) raises ActiveRecord::RecordNotFound, i.e. no active assignment with the given ID exists (missing, deleted, or soft-deleted via a non-'active' workflow state). It is converted into a GraphQL ExecutionError 'Assignment not found'.

Solutions

1. Verify the assignmentId exists: Assignment.active.find(id) in the Rails console on the correct shard.
2. Check the assignment's workflow_state — a deleted assignment will not be found by the active scope.
3. Refresh the client's assignment data; the assignment may have been deleted after page load.
4. Confirm you are operating on the correct Canvas environment/shard and root account.

Example fix

// before
mutation { createAllocationRules(input: { assignmentId: "999999", ... }) } // ID deleted/nonexistent
// after: resolve a live assignment first
assignment = course.assignments.active.where(name: "Peer Review 1").first!
# use assignment.id (GlobalID string) in the mutation input

const assignment = await canvasApi.getAssignment(courseId, assignmentId);
if (!assignment || assignment.workflow_state !== 'active') {
  throw new Error(`Assignment ${assignmentId} is missing or not active`);
}
// then run the allocation rule mutation

function isActiveAssignment(a) {
  return a != null && typeof a.id === 'string' && a.workflow_state === 'active';
}

try {
  await createAllocationRules({ assignmentId, ... });
} catch (e) {
  if (e.message.includes('Assignment not found')) {
    // refetch assignment list; id may be deleted or from another environment
  }
}

When it happens

Trigger: Calling an allocation-rule mutation with an assignmentId that does not exist, belongs to a deleted assignment (workflow_state != 'active'), is on the wrong shard/root account, or is a malformed/nonexistent ID in the environment.

Common situations: Staging IDs used against production data; the assignment was deleted after the UI loaded; the assignment is 'soft deleted' so active scope excludes it; cross-shard ID handling issues in multi-shard Canvas installs.

Understand the failure class

Background: Record Not Found Errors: "not found", RecordNotFound, and "was not found" — what they mean and how to fix them — this error's family across 28 libraries.

Related errors

• A maximum of 50 assessees can be provided at once
• A maximum of 50 assessors can be provided at once
• Allocation rule not found
• An assignment with that id does not exist
• Assignment has self assessments or due date has passed

AI-assisted analysis of instructure/canvas-lms@1c9f0bb801 (2026-09-15). Data as JSON: /api/errors/a448a18cf0046c8f. Report an issue: GitHub.

Appendix: source

Thrown at app/graphql/mutations/allocation_rule_base.rb:117

      if assessor_ids.empty?
        raise GraphQL::ExecutionError, I18n.t("At least one assessor is required")
      end
      if assessee_ids.empty?
        raise GraphQL::ExecutionError, I18n.t("At least one assessee is required")
      end

      if assessor_ids.length > 50
        raise GraphQL::ExecutionError, I18n.t("A maximum of 50 assessors can be provided at once")
      end
      if assessee_ids.length > 50
        raise GraphQL::ExecutionError, I18n.t("A maximum of 50 assessees can be provided at once")
      end
    end

    def get_assignment(assignment_id)
      Assignment.active.find(assignment_id)
    rescue ActiveRecord::RecordNotFound
      raise GraphQL::ExecutionError, I18n.t("Assignment not found")
    end

    def process_allocation_rules(allocation_rules)
      if allocation_rules.all?(&:valid?)
        allocation_rules.each(&:save!)
        { allocation_rules: }
      else
        invalid_rules = allocation_rules.reject(&:valid?)
        all_allocation_errors = []

        invalid_rules.each do |invalid_rule|
          rule_errors = allocation_errors_for(invalid_rule)
          all_allocation_errors.concat(rule_errors[:allocation_errors])
        end

        {
          allocation_errors: all_allocation_errors
        }

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