feat(Tag): Implement add and remove project tag endpoints

[geoffreykwan]

Changes

• Added endpoint to retrieve user tags
• Added endpoint to add tag to project
• Added endpoint to remove tag from project

Test

• Test with and use testing instructions in feat(Teacher): Implement apply tags button WISE-Client#1687

[hirokiterashima]

LGTM.

The body of TagProjectController.addTagToProjects() and TagProjectController.removeTagFromProjects() have some duplicate code. Can you extract common code to another method before you merge?

   User user = userService.retrieveUserByUsername(auth.getName());
   UserTag userTag = getOrCreateTag(user, tag);
   List<Project> projects = getProjects(projectIds);

[geoffreykwan]

How would you extract the common code?

[hirokiterashima]

I would introduce a new private method like this:

  @PutMapping("/projects/tag/{tag}")
  protected ResponseEntity<List<Map<String, Object>>> addTagToProjects(Authentication auth,
      @RequestBody List<Long> projectIds, @PathVariable("tag") String tag) throws Exception {
    return addTagToProjects(auth, projectIds, tag, true);
  }

  @DeleteMapping("/projects/tag/{tag}")
  protected ResponseEntity<List<Map<String, Object>>> removeTagFromProjects(Authentication auth,
      @RequestParam List<Long> projectIds, @PathVariable("tag") String tag) throws Exception {
    return addTagToProjects(auth, projectIds, tag, false);
  }

  private ResponseEntity<List<Map<String, Object>>> addTagToProjects(Authentication auth,
      List<Long> projectIds, String tag, boolean add) throws ObjectNotFoundException {
    User user = userService.retrieveUserByUsername(auth.getName());
    UserTag userTag = getOrCreateTag(user, tag);
    List<Project> projects = getProjects(projectIds);
    for (Project project : projects) {
      if (add) {
        userTagsService.applyTag(project, userTag);
      } else {
        userTagsService.removeTag(project, userTag);
      }
    }
    return ResponseEntityGenerator.createSuccess(createProjectsResponse(user, projects));
  }