Cedric van Putten
30a3e6e8df
Summary: Node 22 doesn't work well with `node-fetch@2`, as one of their polyfills is using the deprecated `punycode` module. This causes unnecessary warnings like: <img width="986" alt="image" src="https://github.com/facebook/react-native/assets/1203991/13f66c5b-b6f4-4894-8576-ca9631d93f77"> Instead of upgrading to the [much larger `node-fetch@3`](https://packagephobia.com/result?p=node-fetch%403.3.2), this change drops `node-fetch` in favor of Node's own built-in `fetch` implementation (using [undici](https://github.com/nodejs/undici#readme)). > Note, `react-native/dev-middleware` [already has the `engines.node >= 18`](https://github.com/facebook/react-native/blob/c7988c9c82793b6b41d4c9190a28ce1202410fa0/packages/dev-middleware/package.json#L38-L40) (which is required for fetch). ## Changelog: [GENERAL] [CHANGED] - Drop `node-fetch` in favor of Node's built-in fetch from `undici` in `react-native/dev-middleware` <!-- Help reviewers and the release process by writing your own changelog entry. Pick one each for the category and type tags: [ANDROID|GENERAL|IOS|INTERNAL] [BREAKING|ADDED|CHANGED|DEPRECATED|REMOVED|FIXED|SECURITY] - Message For more details, see: https://reactnative.dev/contributing/changelogs-in-pull-requests Pull Request resolved: https://github.com/facebook/react-native/pull/45227 Test Plan: See CI for passing tests Reviewed By: NickGerleman Differential Revision: D59202017 Pulled By: robhogan fbshipit-source-id: 15da5d5602e63958b8a3dc581dc1512649f16c12
@react-native/dev-middleware
Dev server middleware supporting core React Native development features. This package is preconfigured in all React Native projects.
Usage
Middleware can be attached to a dev server (e.g. Metro) using the createDevMiddleware API.
import { createDevMiddleware } from '@react-native/dev-middleware';
function myDevServerImpl(args) {
...
const {middleware, websocketEndpoints} = createDevMiddleware({
projectRoot: metroConfig.projectRoot,
serverBaseUrl: `http://${args.host}:${args.port}`,
logger,
});
await Metro.runServer(metroConfig, {
host: args.host,
...,
unstable_extraMiddleware: [
middleware,
// Optionally extend with additional HTTP middleware
],
websocketEndpoints: {
...websocketEndpoints,
// Optionally extend with additional WebSocket endpoints
},
});
}
Included middleware
@react-native/dev-middleware is designed for integrators such as @expo/dev-server and @react-native/community-cli-plugin. It provides a common default implementation for core React Native dev server responsibilities.
We intend to keep this to a narrow set of functionality, based around:
- Debugging — The Chrome DevTools protocol (CDP) endpoints supported by React Native, including the Inspector Proxy, which facilitates connections with multiple devices.
- Dev actions — Endpoints implementing core Dev Menu actions, e.g. reloading the app, opening the debugger frontend.
HTTP endpoints
DevMiddlewareAPI.middleware
These are exposed as a connect middleware handler, assignable to Metro.runServer or other compatible HTTP servers.
GET /json/list, /json (CDP)
Returns the list of available WebSocket targets for all connected React Native app sessions.
GET /json/version (CDP)
Returns version metadata used by Chrome DevTools.
GET /debugger-frontend
Subpaths of this endpoint are reserved to serve the JavaScript debugger frontend.
POST /open-debugger
Open the JavaScript debugger for a given CDP target (direct Hermes debugging).
Example
curl -X POST 'http://localhost:8081/open-debugger?appId=com.meta.RNTester'
WebSocket endpoints
DevMiddlewareAPI.websocketEndpoints
/inspector/device
WebSocket handler for registering device connections.
/inspector/debug
WebSocket handler that proxies CDP messages to/from the corresponding device.
Contributing
Changes to this package can be made locally and tested against the rn-tester app, per the Contributing guide. During development, this package is automatically run from source with no build step.