Future _handlePullRequest()

in app_dart/lib/src/request_handlers/github_webhook.dart [89:144]
42 lines of code
17 McCabe index (conditional complexity)

  Future<void> _handlePullRequest(
    String rawRequest,
  ) async {
    final PullRequestEvent? pullRequestEvent = await _getPullRequestEvent(rawRequest);
    if (pullRequestEvent == null) {
      throw const BadRequestException('Expected pull request event.');
    }
    final String? eventAction = pullRequestEvent.action;
    final PullRequest pr = pullRequestEvent.pullRequest!;

    // See the API reference:
    // https://developer.github.com/v3/activity/events/types/#pullrequestevent
    // which unfortunately is a bit light on explanations.
    log.fine('Processing $eventAction for ${pr.htmlUrl}');
    switch (eventAction) {
      case 'closed':
        // If it was closed without merging, cancel any outstanding tryjobs.
        // We'll leave unfinished jobs if it was merged since we care about those
        // results.
        if (!pr.merged!) {
          await scheduler.cancelPreSubmitTargets(pullRequest: pr, reason: 'Pull request closed');
        } else {
          // Merged pull requests can be added to CI.
          await scheduler.addPullRequest(pr);
        }
        break;
      case 'edited':
        // Editing a PR should not trigger new jobs, but may update whether
        // it has tests.
        await _checkForLabelsAndTests(pullRequestEvent);
        break;
      case 'opened':
      case 'ready_for_review':
      case 'reopened':
        // These cases should trigger LUCI jobs.
        await _checkForLabelsAndTests(pullRequestEvent);
        await _scheduleIfMergeable(pullRequestEvent);
        break;
      case 'labeled':
        break;
      case 'synchronize':
        // This indicates the PR has new commits. We need to cancel old jobs
        // and schedule new ones.
        await _scheduleIfMergeable(pullRequestEvent);
        break;
      // Ignore the rest of the events.
      case 'unlabeled':
      case 'assigned':
      case 'locked':
      case 'review_request_removed':
      case 'review_requested':
      case 'unassigned':
      case 'unlocked':
        break;
    }
  }