Function build

packages/container/src/index.ts:366–404

(options: BuildOptions)

}

export async function build(options: BuildOptions): Promise<BuildResultV2> {
  const image = await withSpan(
    options.span,
    'container.resolve_image',
    { 'service.name': options.service?.name },
    span => resolveImageHandler(options, span)
  );

  const command = normalizeCommand(options.config.command);

  // Do a normal build: the function lands at the natural `index` path and a
  // catch-all route forwards every request to it. Without it there is no `/`
  // route, so for a service the top-level service rewrite resolves to nothing
  // (vercel/vercel#16648), and for a root (non-service) container deploy
  // nothing reaches the function at all. The filesystem handler resolves `/`
  // to the `index` output. The only service-specific concern — nesting the
  // output under `services/<name>/` — is handled by the CLI, not here.
  const routes = [
    { handle: 'filesystem' as const },
    { src: '/(.*)', dest: '/index' },
  ];

  return {
    routes,
    output: {
      index: {
        type: 'Lambda',
        files: {},
        // For `runtime: 'container'` the OCI image reference is carried in
        // `handler`; the platform surfaces it as the container image downstream
        // (vercel/api#76729).
        handler: image,
        runtime: 'container',
        environment: {},
        ...(command ? { command } : {}),
      } as any,
    },
  };
}