Move /status into community-cli-plugin

packages/community-cli-plugin/src/dev-server/__tests__/createDevServerMiddleware-test.js

@@ -31,6 +31,7 @@ beforeEach(async () => {
     .use(
       createDevServerMiddleware({
         serverBaseUrl: new URL(baseUrl),
+        projectRoot: '/project',
         watchFolders: ['/project'],
       }),
     )
@@ -46,8 +47,15 @@ afterEach(() => {
 });
 
 describe('createDevServerMiddleware', () => {
+  test('serves /status', async () => {
+    const resp = await fetch(baseUrl + '/status');
+
+    expect(resp.status).toBe(200);
+    expect(await resp.text()).toBe('packager-status:running');
+  });
+
   test('refuses a cross-origin request before any route', async () => {
-    const resp = await fetch(baseUrl + '/open-url', {
+    const resp = await fetch(baseUrl + '/status', {
       headers: {Origin: 'https://example.com'},
     });
 

packages/community-cli-plugin/src/dev-server/__tests__/statusMiddleware-test.js

@@ -0,0 +1,45 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ */
+
+import statusMiddleware from '../statusMiddleware';
+import connect from 'connect';
+import http from 'node:http';
+
+jest.useRealTimers();
+
+async function fetchStatus(projectRoot: string): Promise<Response> {
+  const app = connect().use('/status', statusMiddleware({projectRoot}));
+  const server = http.createServer(app);
+  await new Promise(resolve => server.listen(0, 'localhost', resolve));
+  try {
+    const address = server.address();
+    if (address == null || typeof address === 'string') {
+      throw new Error('Expected the server to listen on a TCP port');
+    }
+    return await fetch(`http://localhost:${address.port}/status`);
+  } finally {
+    server.closeAllConnections();
+    await new Promise(resolve => server.close(() => resolve()));
+  }
+}
+
+describe('/status', () => {
+  // React Native apps and `isDevServerRunning` depend on this exact response.
+  test('reports that the packager is running for the project root', async () => {
+    const resp = await fetchStatus('/mocked/path');
+
+    expect(resp.status).toBe(200);
+    expect(await resp.text()).toBe('packager-status:running');
+    expect(resp.headers.get('X-React-Native-Project-Root')).toBe(
+      '/mocked/path',
+    );
+    expect(resp.headers.get('Cache-Control')).toBe('no-store');
+  });
+});

packages/community-cli-plugin/src/dev-server/createDevServerMiddleware.js

@@ -13,12 +13,14 @@ import type {Server} from 'connect';
 import openStackFrameMiddleware from './openStackFrameMiddleware';
 import openURLMiddleware from './openURLMiddleware';
 import securityHeadersMiddleware from './securityHeadersMiddleware';
+import statusMiddleware from './statusMiddleware';
 import compression from 'compression';
 import connect from 'connect';
 import nocache from 'nocache';
 
 type Options = Readonly<{
   serverBaseUrl: URL,
+  projectRoot: string,
   watchFolders: ReadonlyArray<string>,
 }>;
 
@@ -28,12 +30,14 @@ type Options = Readonly<{
  */
 export default function createDevServerMiddleware({
   serverBaseUrl,
+  projectRoot,
   watchFolders,
 }: Options): Server {
   return connect()
     .use(securityHeadersMiddleware({serverBaseUrl}))
     .use(compression())
     .use(nocache())
     .use('/open-stack-frame', openStackFrameMiddleware({watchFolders}))
-    .use('/open-url', openURLMiddleware());
+    .use('/open-url', openURLMiddleware())
+    .use('/status', statusMiddleware({projectRoot}));
 }

packages/community-cli-plugin/src/dev-server/isDevServerRunning.js

@@ -33,7 +33,6 @@ export default async function isDevServerRunning(
       return 'not_running';
     }
 
-    // FIXME: Depends on @react-native-community/cli-server-api
     const statusResponse = await fetch(`${devServerUrl}/status`);
     const body = await statusResponse.text();
 

packages/community-cli-plugin/src/dev-server/loadCommunityMiddleware.js

@@ -41,8 +41,6 @@ const unusedMiddlewareStub: Server = {};
 // (@react-native-community/cli-server-api) and should be migrated into core.
 // e.g. used by packages/react-native/Libraries/Core/Devtools/:
 // - /symbolicate
-// e.g. used by ./isDevServerRunning.js:
-// - /status
 const communityMiddlewareFallback: DevServerMiddlewareFactory = () => ({
   middleware: unusedMiddlewareStub,
   websocketEndpoints: {},

packages/community-cli-plugin/src/dev-server/runDevServer.js

@@ -125,6 +125,7 @@ async function runDevServer(
   });
   const pluginMiddleware = createDevServerMiddleware({
     serverBaseUrl: new URL(devServerUrl),
+    projectRoot,
     watchFolders: [unstable_serverRoot ?? projectRoot, ...watchFolders],
   });
 

packages/community-cli-plugin/src/dev-server/statusMiddleware.js

@@ -0,0 +1,31 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ */
+
+import type {NextHandleFunction} from 'connect';
+
+type Options = Readonly<{
+  projectRoot: string,
+}>;
+
+/**
+ * Report that this dev server is running for `projectRoot`, so that the app
+ * and `isDevServerRunning` can tell it from another process on the port.
+ */
+export default function statusMiddleware({
+  projectRoot,
+}: Options): NextHandleFunction {
+  const projectRootHeader = new URL(`file:///${projectRoot}`).pathname.slice(1);
+
+  return (req, res) => {
+    res.setHeader('X-React-Native-Project-Root', projectRootHeader);
+    res.setHeader('Cache-Control', 'no-store');
+    res.end('packager-status:running');
+  };
+}