Function buildHandlerWithGoMod

packages/go/src/index.ts:367–545

* Build the Go function where the package name is not `"main"`. If a `go.mod` * does not exist, a default one will be used.

({
  downloadPath,
  entrypoint,
  entrypointAbsolute,
  entrypointDirname,
  go,
  goModPath,
  handlerFunctionName,
  isGoModInRootDir,
  outDir,
  packageName,
  undo,
}: BuildHandlerOptions)

 * does not exist, a default one will be used.
 */
async function buildHandlerWithGoMod({
  downloadPath,
  entrypoint,
  entrypointAbsolute,
  entrypointDirname,
  go,
  goModPath,
  handlerFunctionName,
  isGoModInRootDir,
  outDir,
  packageName,
  undo,
}: BuildHandlerOptions): Promise<void> {
  debug(
    `Building Go handler as package "${packageName}" (with${
      goModPath ? '' : 'out'
    } go.mod)`
  );

  let goModDirname: string | undefined;

  if (goModPath !== undefined) {
    goModDirname = dirname(goModPath);

    // first we backup the original
    const backupFile = join(goModDirname, `__vc_go.mod.bak`);
    await copy(goModPath, backupFile);

    undo.fileActions.push({
      to: goModPath,
      from: backupFile,
    });

    const goSumPath = join(goModDirname, 'go.sum');
    const isGoSumExists = await pathExists(goSumPath);
    if (!isGoSumExists) {
      // remove the `go.sum` file that will be generated as well
      undo.fileActions.push({
        to: undefined, // delete
        from: goSumPath,
      });
    }
  }

  // Detect vendored dependencies by checking for vendor/modules.txt,
  // the canonical marker created by `go mod vendor`
  const vendorModulesPath = join(
    goModDirname || entrypointDirname,
    'vendor',
    'modules.txt'
  );
  const isVendored = await pathExists(vendorModulesPath);
  if (isVendored) {
    debug('Detected vendor directory in project');

    const vendorModulesBackup = vendorModulesPath + '.bak';
    await copy(vendorModulesPath, vendorModulesBackup);
    undo.fileActions.push({