Method _getVercelConfig

packages/cli/src/util/dev/server.ts:638–866

()

  }

  async _getVercelConfig(): Promise<VercelConfig> {
    const { compileVercelConfig } = await import('../compile-vercel-config');
    await compileVercelConfig(this.cwd);
    const configPath = getVercelConfigPath(this.cwd);

    const [
      pkg = null,
      // The default empty `vercel.json` is used to serve all
      // files as static when no `vercel.json` is present
      vercelConfig = { version: 2, [fileNameSymbol]: 'vercel.json' },
    ] = await Promise.all([
      this.readJsonFile<PackageJson>('package.json'),
      this.readJsonFile<VercelConfig>(configPath),
    ]);

    await this.validateVercelConfig(vercelConfig);

    this.projectSettings = {
      ...this.originalProjectSettings,
      ...pickOverrides(vercelConfig),
    };

    const { error: routeError, routes: maybeRoutes } =
      getTransformedRoutes(vercelConfig);
    if (routeError) {
      output.prettyError(routeError);
      await this.exit();
    }
    vercelConfig.routes = maybeRoutes || [];

    // no builds -> zero config
    //
    // Skip zero-config builder detection when the dev server already has
    // resolved services (`experimentalServices`/`experimentalServicesV2`): the
    // services orchestrator owns building and running them. Without this,
    // `detectBuilders` runs with the remote `framework: "services"` setting but
    // no service config threaded in, and errors with "no services declared".
    const hasResolvedServices = !!this.services && this.services.length > 0;
    if (
      !vercelConfig.experimentalServices &&
      !hasResolvedServices &&
      (!vercelConfig.builds || vercelConfig.builds.length === 0)
    ) {
      const featHandleMiss = true; // enable for zero config
      const { projectSettings, cleanUrls, trailingSlash } = vercelConfig;

      const files = (await getFiles(this.cwd, {})).map(f =>
        relative(this.cwd, f)
      );

      const detectedBuilders = await detectBuilders(files, pkg, {
        tag: 'latest',
        functions: vercelConfig.functions,
        projectSettings: projectSettings || this.projectSettings,
        featHandleMiss,
        cleanUrls,
        trailingSlash,
        workPath: this.cwd,