REST fallback in golang code

Signed-off-by: Lukasz Gryglicki <[email protected]>

Assisted by [OpenAI](https://platform.openai.com/)

Assisted by [GitHub Copilot](https://github.com/features/copilot)

Author: lukaszgryglicki

cla-backend-go/github/github_repository.go

@@ -1220,6 +1220,82 @@ func GetCommitAuthorsSignedStatuses(
 	return signed, unsigned
 }
 
+func GetPullRequestCommitAuthorsREST(ctx context.Context, usersService users.Service, installationID int64, pullRequestID int, owner, repo string, withCoAuthors bool) ([]*UserCommitSummary, bool, error) {
+	f := logrus.Fields{
+		"functionName":  "github.github_repository.GetPullRequestCommitAuthorsREST",
+		"pullRequestID": pullRequestID,
+		"withCoAuthors": withCoAuthors,
+	}
+	var userCommitSummary []*UserCommitSummary
+	var mu sync.Mutex
+
+	client, err := NewGithubAppClient(installationID)
+	if err != nil {
+		log.WithFields(f).WithError(err).Warn("unable to create Github client")
+		return nil, false, err
+	}
+
+	commits, resp, comErr := client.PullRequests.ListCommits(ctx, owner, repo, pullRequestID, &github.ListOptions{})
+	if comErr != nil {
+		log.WithFields(f).WithError(comErr).Warnf("problem listing commits for repo: %s/%s pull request: %d", owner, repo, pullRequestID)
+		return nil, false, comErr
+	}
+	if resp.StatusCode != http.StatusOK {
+		msg := fmt.Sprintf("unexpected status code: %d - expected: %d", resp.StatusCode, http.StatusOK)
+		log.WithFields(f).Warn(msg)
+		return nil, false, errors.New(msg)
+	}
+
+	log.WithFields(f).Debugf("found %d commits for pull request: %d", len(commits), pullRequestID)
+	anyMissing := false
+	for _, commit := range commits {
+		log.WithFields(f).Debugf("loaded commit: %+v", commit)
+		commitAuthor := ""
+		if commit != nil && commit.Commit != nil && commit.Commit.Author != nil && commit.Commit.Author.Login != nil {
+			log.WithFields(f).Debugf("commit.Commit.Author.Login: %s", utils.StringValue(commit.Commit.Author.Login))
+			commitAuthor = utils.StringValue(commit.Commit.Author.Login)
+		} else if commit != nil && commit.Author != nil && commit.Author.Login != nil {
+			log.WithFields(f).Debugf("commit.Author.Login: %s", utils.StringValue(commit.Author.Login))
+			commitAuthor = utils.StringValue(commit.Author.Login)
+		}
+		name, email := "", ""
+		if commit != nil && commit.Commit != nil && commit.Commit.Author != nil {
+			name = strings.TrimSpace(utils.StringValue(commit.Commit.Author.Name))
+			email = strings.TrimSpace(utils.StringValue(commit.Commit.Author.Email))
+			if (name != "" || email != "") && commit.Author == nil {
+				commit.Author = &github.User{}
+			}
+			if name != "" && commit.Author != nil {
+				if commit.Author.Name == nil || strings.TrimSpace(utils.StringValue(commit.Author.Name)) == "" {
+					n := name
+					commit.Author.Name = &n
+				}
+			}
+			if email != "" && commit.Author != nil {
+				if commit.Author.Email == nil || strings.TrimSpace(utils.StringValue(commit.Author.Email)) == "" {
+					e := email
+					commit.Author.Email = &e
+				}
+			}
+		}
+		log.WithFields(f).Debugf("commitAuthor: %s, name: %s, email: %s", commitAuthor, name, email)
+		userCommitSummary = append(userCommitSummary, &UserCommitSummary{
+			SHA:          utils.StringValue(commit.SHA),
+			CommitAuthor: commit.Author,
+			Affiliated:   false,
+			Authorized:   false,
+		})
+		if withCoAuthors {
+			missing := ExpandWithCoAuthors(ctx, client, usersService, commit, pullRequestID, installationID, &userCommitSummary, &mu)
+			if !anyMissing && missing {
+				anyMissing = true
+			}
+		}
+	}
+
+	return userCommitSummary, anyMissing, nil
+}
+
 func GetPullRequestCommitAuthors(
 	ctx context.Context,
 	usersService users.Service,
@@ -1302,7 +1378,7 @@ query($owner:String!, $name:String!, $number:Int!, $pageSize:Int!, $cursor:Strin
 		var page prCommitsPage
 		if _, err := doGraphQL(ctx, client, query, vars, &page); err != nil {
 			log.WithFields(f).WithError(err).Warnf("problem listing commits via GraphQL for %s/%s PR #%d", owner, repo, pullRequestID)
-			return nil, false, err
+			return GetPullRequestCommitAuthorsREST(ctx, usersService, installationID, pullRequestID, owner, repo, withCoAuthors)
 		}
 
 		c := page.Repository.PullRequest.Commits