Function getRepoBranch

src/api/utils/github.ts:110–171

(
  owner: string,
  repo: string,
  env: CloudflareEnvironment,
)

 * @throws Error if the default branch cannot be determined
 */
export async function getRepoBranch(
  owner: string,
  repo: string,
  env: CloudflareEnvironment,
): Promise<string> {
  try {
    // First try to get the actual default branch using GitHub API
    const apiUrl = `https://api.github.com/repos/${owner}/${repo}`;
    const response = await githubApiRequest(apiUrl, {}, env);

    if (response && response.ok) {
      const data = (await response.json()) as { default_branch?: string };
      if (data && data.default_branch) {
        console.log("Default branch found", data.default_branch);
        return data.default_branch;
      }
    }

    console.error(
      "No default branch found, falling back to main/master check",
      response,
    );

    // Fall back to the main/master check if API request fails
    // Try 'main' branch
    const mainUrl = constructGithubUrl(owner, repo, "main", "README.md");
    const mainResponse = await githubApiRequest(
      mainUrl,
      { method: "HEAD" },
      env,
    );

    if (mainResponse && mainResponse.ok) {
      return "main";
    }

    // If 'main' branch doesn't exist, try 'master'
    const masterUrl = constructGithubUrl(owner, repo, "master", "README.md");
    const masterResponse = await githubApiRequest(
      masterUrl,
      { method: "HEAD" },
      env,
    );

    if (masterResponse && masterResponse.ok) {
      return "master";
    }

    // If neither branch exists, throw an error
    throw new Error(
      `Could not determine default branch for ${owner}/${repo}. Neither 'main' nor 'master' branches found.`,
    );
  } catch (error) {
    console.error(
      `Error determining default branch for ${owner}/${repo}:`,
      error,
    );
    // Default to 'main' in case of network errors or other issues