Integrated code lifecycle: Simplify repository handling for commit history

[krusche]

Checklist

General

• I tested all changes and their related features with all corresponding user types on a test server.
• I chose a title conforming to the naming conventions for pull requests.

Server

• Important: I implemented the changes with a very good performance and prevented too many (unnecessary) database calls.
• I strictly followed the server coding and design guidelines.
• I documented the Java code using JavaDoc style.

Client

• I strictly followed the client coding and design guidelines.
• I added multiple integration tests (Jest) related to the features (with a high test coverage), while following the test guidelines.
• I documented the TypeScript code using JSDoc style.

Changes affecting Programming Exercises

• High priority: I tested all changes and their related features with all corresponding user types on a test server configured with the integrated lifecycle setup (LocalVC and LocalCI).

Motivation and Context

To compare commits, the commit detail view retrieves the content of a repository. This always involved the server having to clone / checkout / pull the local repository at each commit, scanning the working copy, then rewinding. On production, this resulted in longer waiting times.

Description

• Some endpoints were changed to allow for handling both regular student participations and the "special" repository types of a programming exercise
• Endpoints used in the commit history view were adjusted to allow retrieving the file content from the bare (remote) repository as well if LocalVC is active. This avoids the process mentioned above.

Steps for Testing

Prerequisites:

• Test Server with LocalVC enabled
• 1 Instructor
• 1 Student
• 1 Programming exercise with
  • 1 regular participation with a few commits
  • A few commits each in the template, test, and solution repositories (you can use Edit in Editor for this)

Template, Test, and Solution repositories

1. Log in as the instructor
2. Navigate to course management > Your course > Exercises > Click on the title of your programming exercise
3. Scroll down to where the template, solution, and test repositories are listed.
4. For each of these repositories, click "Open Repository," then go to the commit history.
5. Verify that you get no errors when viewing the history and that the commits you made are listed and correctly displayed when you click on them.

Regular participations

6. Log in as the student
7. Navigate to courses > your course > your exercise > Open repository
8. Verify that you get no errors when viewing the history and that the commits you made are listed and correctly displayed when you click on them.

Testserver States

Note

These badges show the state of the test servers.
Green = Currently available, Red = Currently locked

Review Progress

Performance Review

• I (as a reviewer) confirm that the client changes (in particular related to REST calls and UI responsiveness) are implemented with a very good performance
• I (as a reviewer) confirm that the server changes (in particular related to database calls) are implemented with a very good performance

Code Review

• Code Review 1
• Code Review 2

Manual Tests

• Test 1
• Test 2

Test Coverage

Client

Class/File	Line Coverage	Confirmation (assert/expect)
programming-exercise-participation.service.ts	93.75%	✅
programming-exercise.service.ts	90.62%	✅
commit-details-view.component.ts	95.08%	✅

Server

Note: More extensive testing of this new functionality will be done in a follow-up PR, as the repository setup of the tests currently does not allow us to test it properly.

Class/File	Line Coverage	Confirmation (assert/expect)
GitService.java	83%	✅
CommitHistoryService.java	87%	✅
ProgrammingExerciseGitDiffReportResource.java	79%	✅
ProgrammingExerciseParticipationResource.java	60%	✅
RepositoryProgrammingExerciseParticipationResource.java	84%	✅
RepositoryResource.java	91%	✅
TestRepositoryResource.java	83%	✅

[BBesrour]

Tested locally:

• Commit history for Test, Template, and Solution open with no error and display correct commits (commit view displays correct changes)
• Same for regular participation

[az108]

Tested on TS2 and works as expected without any errors and all commits being displayed correctly. Code LGTM

[florian-glombik]

The code looks good to me 👍

[kaancayli]

Tested on TS2. Works as expected. Code lgtm