Implementation strategy

This page provides a brief overview of key interactions between your add-on web application and the Google Classroom add-ons API.

Attachment Discovery iframe

The Attachment Discovery iframe is the landing page for teachers in your add-on. Consider taking the following actions regarding this view:

• When the Attachment Discovery iframe opens, make a courseWork.GetAddOnContextRequest, courseWorkMaterials.GetAddOnContextRequest or announcements.GetAddOnContextRequest based on the itemType to validate user role and get the supportsStudentWork value.
• Show your content discovery or creation UI. You might omit activity-type attachments based on the value of supportsStudentWork from the launch validation response.
• Based on teacher selections, make one or more add-on create requests to add attachments to the assignment.

Other iframes

The Student View iframe, Student Work Review iframe, and Teacher View iframe are all intended to present content to the user rather than modifying a Classroom assignment. Consider taking the following actions regarding these views:

• When an iframe opens, get the user's OAuth consent and then validate their role and attachment ID.

  • If the current user is a student, associate the submissionId from the response with the student work. This is required for passing back grades and for showing student work to teachers in the grading tool; the submissionIds match across views.
  • If the attachmentId is already known to the add-on, show the appropriate attachment UI.
  • Otherwise, it must be the case that the parent post of this attachment was copied from another post or course. Use copyHistory to identify the most recent copy that the add-on is aware of and copy the settings from it to create a new corresponding model of the attachment on the add-on side. Then, show the appropriate attachment UI.
  Important: You may encounter an edge case here; the first user to access this attachment might be a student.