E2057. Time travel Not Allowed..!!! Restrict TAs’ ability to change their own grade + limit file-size upload

This page provides a description of the Expertiza based OSS project.

Problem Statement

If a person is listed as a TA in one course and as a student in another course, then if they navigate to the "Your scores" page of one of the assignments in which they are participating as a student, they can see a TA's view of that page - effectively allowing them to assign their own grade!

The below screenshot shows the TA view for the course he is added as the TA:

As evident from the screenshot, the user, "student003" is assigned as a TA for CSC502.

The user, "student003" is also a student in the course, CSC501:

The issue here is that this user, "student003" who is a TA in one course is able to alter the grades for his assignments in other courses he is taking in the semester:

Solutions

Once TA clicks on Assignment > view scores, they will no longer be able to see the form to add/edit the grade and comment for the course in which they are participating as a student.

Files modified: view_team.html

We are rendering the TA view(to grade and comment) only if the TA ID has an entry in the ta_mapping table. This ensures that the TA will be able modify the grades for courses for which they are assigned as TA.

• Get the course ID for the course which the student is currently viewing.
• Get the user ID, which will be teacher ID as well
• Using these two fields we are restricting the access for the student to modify the grades.

Only for the courses for which a user is a TA, he will be able to see 'TA Grade-Comment:' section under Assignment > view scores

The green-highlighted lines indicate the changes.

Below is the screenshot which indicates the TA view for which the user is registered as a student: