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files /dev/null and b/public/images/docs/performance-tracks/scheduler.png differ diff --git a/public/images/docs/performance-tracks/server-overview.dark.png b/public/images/docs/performance-tracks/server-overview.dark.png new file mode 100644 index 000000000..221fb1204 Binary files /dev/null and b/public/images/docs/performance-tracks/server-overview.dark.png differ diff --git a/public/images/docs/performance-tracks/server-overview.png b/public/images/docs/performance-tracks/server-overview.png new file mode 100644 index 000000000..85c7eed27 Binary files /dev/null and b/public/images/docs/performance-tracks/server-overview.png differ diff --git a/src/components/MDX/Sandpack/template.ts b/src/components/MDX/Sandpack/template.ts index 358c8616e..ed594887b 100644 --- a/src/components/MDX/Sandpack/template.ts +++ b/src/components/MDX/Sandpack/template.ts @@ -35,8 +35,8 @@ root.render( eject: 'react-scripts eject', }, dependencies: { - react: '^19.1.0', - 'react-dom': '^19.1.0', + react: '^19.2.0', + 'react-dom': '^19.2.0', 'react-scripts': '^5.0.0', }, }, diff --git a/src/components/MDX/SandpackWithHTMLOutput.tsx b/src/components/MDX/SandpackWithHTMLOutput.tsx index c5149deb9..49e980d32 100644 --- a/src/components/MDX/SandpackWithHTMLOutput.tsx +++ b/src/components/MDX/SandpackWithHTMLOutput.tsx @@ -56,8 +56,8 @@ export default function formatHTML(markup) { const packageJSON = ` { "dependencies": { - "react": "18.3.0-canary-6db7f4209-20231021", - "react-dom": "18.3.0-canary-6db7f4209-20231021", + "react": "^19.2.0", + "react-dom": "^19.2.0", "react-scripts": "^5.0.0", "html-format": "^1.1.2" }, diff --git a/src/content/blog/2025/04/21/react-compiler-rc.md b/src/content/blog/2025/04/21/react-compiler-rc.md index 2ebbf3bae..ce30a8860 100644 --- a/src/content/blog/2025/04/21/react-compiler-rc.md +++ b/src/content/blog/2025/04/21/react-compiler-rc.md @@ -57,23 +57,23 @@ During the RC period, we encourage all React users to try the compiler and provi As noted in the Beta announcement, React Compiler is compatible with React 17 and up. If you are not yet on React 19, you can use React Compiler by specifying a minimum target in your compiler config, and adding `react-compiler-runtime` as a dependency. You can find docs on this [here](https://react.dev/learn/react-compiler#using-react-compiler-with-react-17-or-18). ## Migrating from eslint-plugin-react-compiler to eslint-plugin-react-hooks {/*migrating-from-eslint-plugin-react-compiler-to-eslint-plugin-react-hooks*/} -If you have already installed eslint-plugin-react-compiler, you can now remove it and use `eslint-plugin-react-hooks@rc`. Many thanks to [@michaelfaith](https://bsky.app/profile/michael.faith) for contributing to this improvement! +If you have already installed eslint-plugin-react-compiler, you can now remove it and use `eslint-plugin-react-hooks@^6.1.1`. Many thanks to [@michaelfaith](https://bsky.app/profile/michael.faith) for contributing to this improvement! To install: npm -{`npm install --save-dev eslint-plugin-react-hooks@rc`} +{`npm install --save-dev eslint-plugin-react-hooks@^6.1.1`} pnpm -{`pnpm add --save-dev eslint-plugin-react-hooks@rc`} +{`pnpm add --save-dev eslint-plugin-react-hooks@^6.1.1`} yarn -{`yarn add --dev eslint-plugin-react-hooks@rc`} +{`yarn add --dev eslint-plugin-react-hooks@^6.1.1`} ```js diff --git a/src/content/blog/2025/04/23/react-labs-view-transitions-activity-and-more.md b/src/content/blog/2025/04/23/react-labs-view-transitions-activity-and-more.md index 5d2c59b76..41c359807 100644 --- a/src/content/blog/2025/04/23/react-labs-view-transitions-activity-and-more.md +++ b/src/content/blog/2025/04/23/react-labs-view-transitions-activity-and-more.md @@ -18,11 +18,9 @@ In React Labs posts, we write about projects in active research and development. -React Conf 2025 is scheduled for October 7–8 in Henderson, Nevada! +React Conf 2025 is scheduled for October 7–8 in Henderson, Nevada! -We're looking for speakers to help us create talks about the features covered in this post. If you're interested in speaking at ReactConf, [please apply here](https://forms.reform.app/react-conf/call-for-speakers/) (no talk proposal required). - -For more info on tickets, free streaming, sponsoring, and more, see [the React Conf website](https://conf.react.dev). +Watch the livestream on [the React Conf website](https://conf.react.dev). @@ -11544,7 +11542,7 @@ Try searching for a video, selecting it, and clicking "back": ```js src/App.js -import { unstable_ViewTransition as ViewTransition, unstable_Activity as Activity } from "react"; import Details from "./Details"; import Home from "./Home"; import { useRouter } from "./router"; +import { unstable_ViewTransition as ViewTransition } from "react"; import Details from "./Details"; import Home from "./Home"; import { useRouter } from "./router"; import { unstable_Activity, Activity as ActivityStable} from 'react'; let Activity = ActivityStable ?? unstable_Activity; export default function App() { const { url } = useRouter(); @@ -12881,7 +12879,7 @@ With this update, if the content on the next page has time to pre-render, it wil ```js src/App.js -import { unstable_ViewTransition as ViewTransition, unstable_Activity as Activity, use } from "react"; import Details from "./Details"; import Home from "./Home"; import { useRouter } from "./router"; import {fetchVideos} from './data' +import { unstable_ViewTransition as ViewTransition, use } from "react"; import Details from "./Details"; import Home from "./Home"; import { useRouter } from "./router"; import {fetchVideos} from './data'; import { unstable_Activity, Activity as ActivityStable} from 'react'; let Activity = ActivityStable ?? unstable_Activity; export default function App() { const { url } = useRouter(); diff --git a/src/content/blog/2025/10/01/react-19-2.md b/src/content/blog/2025/10/01/react-19-2.md new file mode 100644 index 000000000..eae9c8fa7 --- /dev/null +++ b/src/content/blog/2025/10/01/react-19-2.md @@ -0,0 +1,339 @@ +--- +title: "React 19.2" +author: The React Team +date: 2025/10/01 +description: React 19.2 adds new features like Activity, React Performance Tracks, useEffectEvent, and more. +--- + +October 1, 2025 by [The React Team](/community/team) + +--- + + + +React 19.2 is now available on npm! + + + +This is our third release in the last year, following React 19 in December and React 19.1 in June. In this post, we'll give an overview of the new features in React 19.2, and highlight some notable changes. + + + +--- + +## New React Features {/*new-react-features*/} + +### `` {/*activity*/} + +`` lets you break your app into "activities" that can be controlled and prioritized. + +You can use Activity as an alternative to conditionally rendering parts of your app: + +```js +// Before +{isVisible && } + +// After + + + +``` + +In React 19.2, Activity supports two modes: `visible` and `hidden`. + +- `hidden`: hides the children, unmounts effects, and defers all updates until React has nothing left to work on. +- `visible`: shows the children, mounts effects, and allows updates to be processed normally. + +This means you can pre-render and keep rendering hidden parts of the app without impacting the performance of anything visible on screen. + +You can use Activity to render hidden parts of the app that a user is likely to navigate to next, or to save the state of parts the user navigates away from. This helps make navigations quicker by loading data, css, and images in the background, and allows back navigations to maintain state such as input fields. + +In the future, we plan to add more modes to Activity for different use cases. + +For examples on how to use Activity, check out the [Activity docs](/reference/react/Activity). + +--- + +### `useEffectEvent` {/*use-effect-event*/} + +One common pattern with `useEffect` is to notify the app code about some kind of "events" from an external system. For example, when a chat room gets connected, you might want to display a notification: + +```js {5,11} +function ChatRoom({ roomId, theme }) { + useEffect(() => { + const connection = createConnection(serverUrl, roomId); + connection.on('connected', () => { + showNotification('Connected!', theme); + }); + connection.connect(); + return () => { + connection.disconnect() + }; + }, [roomId, theme]); + // ... +``` + +The problem with the code above is that a change to any values used inside such an "event" will cause the surrounding Effect to re-run. For example, changing the `theme` will cause the chat room to reconnect. This makes sense for values related to the Effect logic itself, like `roomId`, but it doesn't make sense for `theme`. + +To solve this, most users just disable the lint rule and exclude the dependency. But that can lead to bugs since the linter can no longer help you keep the dependencies up to date if you need to update the Effect later. + +With `useEffectEvent`, you can split the "event" part of this logic out of the Effect that emits it: + +```js {2,3,4,9} +function ChatRoom({ roomId, theme }) { + const onConnected = useEffectEvent(() => { + showNotification('Connected!', theme); + }); + + useEffect(() => { + const connection = createConnection(serverUrl, roomId); + connection.on('connected', () => { + onConnected(); + }); + connection.connect(); + return () => connection.disconnect(); + }, [roomId]); // ✅ All dependencies declared (Effect Events aren't dependencies) + // ... +``` + +Similar to DOM events, Effect Events always “see” the latest props and state. + +**Effect Events should _not_ be declared in the dependency array**. You'll need to upgrade to `eslint-plugin-react-hooks@6.1.1` so that the linter doesn't try to insert them as dependencies. Note that Effect Events can only be declared in the same component or Hook as "their" Effect. These restrictions are verified by the linter. + + + +#### When to use `useEffectEvent` {/*when-to-use-useeffectevent*/} + +You should use `useEffectEvent` for functions that are conceptually "events" that happen to be fired from an Effect instead of a user event (that's what makes it an "Effect Event"). You don't need to wrap everything in `useEffectEvent`, or to use it just to silence the lint error, as this can lead to bugs. + +For a deep dive on how to think about Event Effects, see: [Separating Events from Effects](/learn/separating-events-from-effects#extracting-non-reactive-logic-out-of-effects). + + + +--- + +### `cacheSignal` {/*cache-signal*/} + + + +`cacheSignal` is only for use with [React Server Components](/reference/rsc/server-components). + + + +`cacheSignal` allows you to know when the [`cache()`](/reference/react/cache) lifetime is over: + +``` +import {cache, cacheSignal} from 'react'; +const dedupedFetch = cache(fetch); + +async function Component() { + await dedupedFetch(url, { signal: cacheSignal() }); +} +``` + +This allows you to clean up or abort work when the result will no longer be used in the cache, such as: + +- React has successfully completed rendering +- The render was aborted +- The render has failed + +For more info, see the [`cacheSignal` docs](/reference/react/cacheSignal). + +--- + +### Performance Tracks {/*performance-tracks*/} + +React 19.2 adds a new set of [custom tracks](https://developer.chrome.com/docs/devtools/performance/extension) to Chrome DevTools performance profiles to provide more information about the performance of your React app: + +
+ + + + + + + + +
+ +The [React Performance Tracks docs](/reference/dev-tools/react-performance-tracks) explain everything included in the tracks, but here is a high-level overview. + +#### Scheduler ⚛ {/*scheduler-*/} + +The Scheduler track shows what React is working on for different priorities such as "blocking" for user interactions, or "transition" for updates inside startTransition. Inside each track, you will see the type of work being performed such as the event that scheduled an update, and when the render for that update happened. + +We also show information such as when an update is blocked waiting for a different priority, or when React is waiting for paint before continuing. The Scheduler track helps you understand how React splits your code into different priorities, and the order it completed the work. + +See the [Scheduler track](/reference/dev-tools/react-performance-tracks#scheduler) docs to see everything included. + +#### Components ⚛ {/*components-*/} + +The Components track shows the tree of components that React is working on either to render or run effects. Inside you'll see labels such as "Mount" for when children mount or effects are mounted, or "Blocked" for when rendering is blocked due to yielding to work outside React. + +The Component track helps you understand when components are rendered or run effects, and the time it takes to complete that work to help identify performance problems. + +See the [Component track docs](/reference/dev-tools/react-performance-tracks#components) for see everything included. + +--- + +## New React DOM Features {/*new-react-dom-features*/} + +### Partial Pre-rendering {/*partial-pre-rendering*/} + +In 19.2 we're adding a new capability to pre-render part of the app ahead of time, and resume rendering it later. + +This feature is called "Partial Pre-rendering", and allows you to pre-render the static parts of your app and serve it from a CDN, and then resume rendering the shell to fill it in with dynamic content later. + +To pre-render an app to resume later, first call `prerender` with an `AbortController`: + +``` +const {prelude, postponed} = await prerender(, { + signal: controller.signal, +}); + +// Save the postponed state for later +await savePostponedState(postponed); + +// Send prelude to client or CDN. +``` + +Then, you can return the `prelude` shell to the client, and later call `resume` to "resume" to a SSR stream: + +``` +const postponed = await getPostponedState(request); +const resumeStream = await resume(, postponed); + +// Send stream to client. +``` + +Or you can call `resumeAndPrerender` to resume to get static HTML for SSG: + +``` +const postponedState = await getPostponedState(request); +const { prelude } = await resumeAndPrerender(, postponedState); + +// Send complete HTML prelude to CDN. +``` + +For more info, see the docs for the new APIs: +- `react-dom/server` + - [`resume`](/reference/react-dom/server/resume): for Web Streams. + - [`resumeToPipeableStream`](/reference/react-dom/server/resumeToPipeableStream) for Node Streams. +- `react-dom/static` + - [`resumeAndPrerender`](/reference/react-dom/static/resumeAndPrerender) for Web Streams. + - [`resumeAndPrerenderToNodeStream`](/reference/react-dom/static/resumeAndPrerenderToNodeStream) for Node Streams. + +Additionally, the prerender apis now return a `postpone` state to pass to the `resume` apis. + +--- + +## Notable Changes {/*notable-changes*/} + +### Batching Suspense Boundaries for SSR {/*batching-suspense-boundaries-for-ssr*/} + +We fixed a behavioral bug where Suspense boundaries would reveal differently depending on if they were rendered on the client or when streaming from server-side rendering. + +Starting in 19.2, React will batch reveals of server-rendered Suspense boundaries for a short time, to allow more content to be revealed together and align with the client-rendered behavior. + + + +Previously, during streaming server-side rendering, suspense content would immediately replace fallbacks. + + + + + +In React 19.2, suspense boundaries are batched for a small amount of time, to allow revealing more content together. + + + +This fix also prepares apps for supporting `` for Suspense during SSR. By revealing more content together, animations can run in larger batches of content, and avoid chaining animations of content that stream in close together. + + + +React uses heuristics to ensure throttling does not impact core web vitals and search ranking. + +For example, if the total page load time is approaching 2.5s (which is the time considered "good" for [LCP](https://web.dev/articles/lcp)), React will stop batching and reveal content immediately so that the throttling is not the reason to miss the metric. + + + +--- + +### SSR: Web Streams support for Node {/*ssr-web-streams-support-for-node*/} + +React 19.2 adds support for Web Streams for streaming SSR in Node.js: +- [`renderToReadableStream`](/reference/react-dom/server/renderToReadableStream) is now available for Node.js +- [`prerender`](/reference/react-dom/static/prerender) is now available for Node.js + +As well as the new `resume` APIs: +- [`resume`](/reference/react-dom/server/resume) is available for Node.js. +- [`resumeAndPrerender`](/reference/react-dom/static/resumeAndPrerender) is available for Node.js. + + + + +#### Prefer Node Streams for server-side rendering in Node.js {/*prefer-node-streams-for-server-side-rendering-in-nodejs*/} + +In Node.js environments, we still highly recommend using the Node Streams APIs: + +- [`renderToPipeableStream`](/reference/react-dom/server/renderToPipeableStream) +- [`resumeToPipeableStream`](/reference/react-dom/server/resumeToPipeableStream) +- [`prerenderToNodeStream`](/reference/react-dom/static/prerenderToNodeStream) +- [`resumeAndPrerenderToNodeStream`](/reference/react-dom/static/resumeAndPrerenderToNodeStream) + +This is because Node Streams are much faster than Web Streams in Node, and Web Streams do not support compression by default, leading to users accidentally missing the benefits of streaming. + + + +--- + +### `eslint-plugin-react-hooks` v6 {/*eslint-plugin-react-hooks*/} + +We also published `eslint-plugin-react-hooks@6.1.1` with flat config by default in the `recommended` preset, and opt-in for new React Compiler powered rules. + +To continue using the legacy config, you can change to `recommended-legacy`: + +```diff +- extends: ['plugin:react-hooks/recommended'] ++ extends: ['plugin:react-hooks/recommended-legacy'] +``` + +For a full list of compiler enabled rules, [check out the linter docs](/reference/eslint-plugin-react-hooks#additional-rules). + +Check out the `eslint-plugin-react-hooks` [changelog for a full list of changes](https://github.com/facebook/react/blob/main/packages/eslint-plugin-react-hooks/CHANGELOG.md#610). + +--- + +### Update the default `useId` prefix {/*update-the-default-useid-prefix*/} + +In 19.2, we're updating the default `useId` prefix from `:r:` (19.0.0) or `«r»` (19.1.0) to `_r_`. + +The original intent of using a special character that was not valid for CSS selectors was that it would be unlikely to collide with IDs written by users. However, to support View Transitions, we need to ensure that IDs generated by `useId` are valid for `view-transition-name` and XML 1.0 names. + +--- + +## Changelog {/*changelog*/} + +Other notable changes +- `react-dom`: Allow nonce to be used on hoistable styles [#32461](https://github.com/facebook/react/pull/32461) +- `react-dom`: Warn for using a React owned node as a Container if it also has text content [#32774](https://github.com/facebook/react/pull/32774) + +Notable bug fixes +- `react`: Stringify context as "SomeContext" instead of "SomeContext.Provider" [#33507](https://github.com/facebook/react/pull/33507) +- `react`: Fix infinite useDeferredValue loop in popstate event [#32821](https://github.com/facebook/react/pull/32821) +- `react`: Fix a bug when an initial value was passed to useDeferredValue [#34376](https://github.com/facebook/react/pull/34376) +- `react`: Fix a crash when submitting forms with Client Actions [#33055](https://github.com/facebook/react/pull/33055) +- `react`: Hide/unhide the content of dehydrated suspense boundaries if they resuspend [#32900](https://github.com/facebook/react/pull/32900) +- `react`: Avoid stack overflow on wide trees during Hot Reload [#34145](https://github.com/facebook/react/pull/34145) +- `react`: Improve component stacks in various places [#33629](https://github.com/facebook/react/pull/33629), [#33724](https://github.com/facebook/react/pull/33724), [#32735](https://github.com/facebook/react/pull/32735), [#33723](https://github.com/facebook/react/pull/33723) +- `react`: Fix a bug with React.use inside React.lazy-ed Component [#33941](https://github.com/facebook/react/pull/33941) +- `react-dom`: Stop warning when ARIA 1.3 attributes are used [#34264](https://github.com/facebook/react/pull/34264) +- `react-dom`: Fix a bug with deeply nested Suspense inside Suspense fallbacks [#33467](https://github.com/facebook/react/pull/33467) +- `react-dom`: Avoid hanging when suspending after aborting while rendering [#34192](https://github.com/facebook/react/pull/34192) + +For a full list of changes, please see the [Changelog](https://github.com/facebook/react/blob/main/CHANGELOG.md). + + +--- + +_Thanks to [Ricky Hanlon](https://bsky.app/profile/ricky.fm) for [writing this post](https://www.youtube.com/shorts/T9X3YkgZRG0), [Dan Abramov](https://bsky.app/profile/danabra.mov), [Matt Carroll](https://twitter.com/mattcarrollcode), [Jack Pope](https://jackpope.me), and [Joe Savona](https://x.com/en_JS) for reviewing this post._ diff --git a/src/content/blog/index.md b/src/content/blog/index.md index a7a897634..0477bb0cc 100644 --- a/src/content/blog/index.md +++ b/src/content/blog/index.md @@ -12,6 +12,12 @@ You can also follow the [@react.dev](https://bsky.app/profile/react.dev) account
+ + +React 19.2 adds new features like Activity, React Performance Tracks, useEffectEvent, and more. In this post ... + + + In React Labs posts, we write about projects in active research and development. In this post, we're sharing two new experimental features that are ready to try today, and sharing other areas we're working on now ... diff --git a/src/content/learn/escape-hatches.md b/src/content/learn/escape-hatches.md index e6b050e0e..ab5f666ad 100644 --- a/src/content/learn/escape-hatches.md +++ b/src/content/learn/escape-hatches.md @@ -312,12 +312,6 @@ Read **[Lifecycle of Reactive Events](/learn/lifecycle-of-reactive-effects)** to ## Separating events from Effects {/*separating-events-from-effects*/} - - -This section describes an **experimental API that has not yet been released** in a stable version of React. - - - Event handlers only re-run when you perform the same interaction again. Unlike event handlers, Effects re-synchronize if any of the values they read, like props or state, are different than during last render. Sometimes, you want a mix of both behaviors: an Effect that re-runs in response to some values but not others. All code inside Effects is *reactive.* It will run again if some reactive value it reads has changed due to a re-render. For example, this Effect will re-connect to the chat if either `roomId` or `theme` have changed: @@ -455,8 +449,8 @@ This is not ideal. You want to re-connect to the chat only if the `roomId` has c ```json package.json hidden { "dependencies": { - "react": "canary", - "react-dom": "canary", + "react": "latest", + "react-dom": "latest", "react-scripts": "latest", "toastify-js": "1.12.0" }, diff --git a/src/content/learn/react-compiler/installation.md b/src/content/learn/react-compiler/installation.md index a40b1f5af..7987e1264 100644 --- a/src/content/learn/react-compiler/installation.md +++ b/src/content/learn/react-compiler/installation.md @@ -173,10 +173,10 @@ React Compiler includes an ESLint rule that helps identify code that can't be op Install the ESLint plugin: -npm install -D eslint-plugin-react-hooks@rc +npm install -D eslint-plugin-react-hooks@^6.1.1 -If you haven't already configured eslint-plugin-react-hooks, follow the [installation instructions in the readme](https://github.com/facebook/react/blob/main/packages/eslint-plugin-react-hooks/README.md#installation). The compiler rule is enabled by default in the latest RC, so no additional configuration is needed. +If you haven't already configured eslint-plugin-react-hooks, follow the [installation instructions in the readme](https://github.com/facebook/react/blob/main/packages/eslint-plugin-react-hooks/README.md#installation). The compiler rules are available in the `recommended-latest` preset. The ESLint rule will: - Identify violations of the [Rules of React](/reference/rules) @@ -246,4 +246,4 @@ Now that you have React Compiler installed, learn more about: - [Configuration options](/reference/react-compiler/configuration) to customize the compiler - [Incremental adoption strategies](/learn/react-compiler/incremental-adoption) for existing codebases - [Debugging techniques](/learn/react-compiler/debugging) for troubleshooting issues -- [Compiling Libraries guide](/reference/react-compiler/compiling-libraries) for compiling your React library \ No newline at end of file +- [Compiling Libraries guide](/reference/react-compiler/compiling-libraries) for compiling your React library diff --git a/src/content/learn/removing-effect-dependencies.md b/src/content/learn/removing-effect-dependencies.md index fb98a0cd1..61eb2e8d6 100644 --- a/src/content/learn/removing-effect-dependencies.md +++ b/src/content/learn/removing-effect-dependencies.md @@ -609,14 +609,6 @@ function ChatRoom({ roomId }) { ### Do you want to read a value without "reacting" to its changes? {/*do-you-want-to-read-a-value-without-reacting-to-its-changes*/} - - -**The `useEffectEvent` API is currently only available in React’s Canary and Experimental channels.** - -[Learn more about React’s release channels here.](/community/versioning-policy#all-release-channels) - - - Suppose that you want to play a sound when the user receives a new message unless `isMuted` is `true`: ```js {3,10-12} @@ -1261,22 +1253,6 @@ Is there a line of code inside the Effect that should not be reactive? How can y -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useState, useEffect, useRef } from 'react'; import { useEffectEvent } from 'react'; @@ -1388,22 +1364,6 @@ Your Effect needs to read the latest value of `duration`, but you don't want it -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useState, useEffect, useRef } from 'react'; import { FadeInAnimation } from './animation.js'; @@ -1827,8 +1787,8 @@ Another of these functions only exists to pass some state to an imported API met ```json package.json hidden { "dependencies": { - "react": "canary", - "react-dom": "canary", + "react": "latest", + "react-dom": "latest", "react-scripts": "latest", "toastify-js": "1.12.0" }, @@ -2122,8 +2082,8 @@ As a result, the chat re-connects only when something meaningful (`roomId` or `i ```json package.json hidden { "dependencies": { - "react": "canary", - "react-dom": "canary", + "react": "latest", + "react-dom": "latest", "react-scripts": "latest", "toastify-js": "1.12.0" }, diff --git a/src/content/learn/reusing-logic-with-custom-hooks.md b/src/content/learn/reusing-logic-with-custom-hooks.md index 2038e59e1..47a4cf52a 100644 --- a/src/content/learn/reusing-logic-with-custom-hooks.md +++ b/src/content/learn/reusing-logic-with-custom-hooks.md @@ -837,14 +837,6 @@ Every time your `ChatRoom` component re-renders, it passes the latest `roomId` a ### Passing event handlers to custom Hooks {/*passing-event-handlers-to-custom-hooks*/} - - -**The `useEffectEvent` API is currently only available in React’s Canary and Experimental channels.** - -[Learn more about React’s release channels here.](/community/versioning-policy#all-release-channels) - - - As you start using `useChatRoom` in more components, you might want to let components customize its behavior. For example, currently, the logic for what to do when a message arrives is hardcoded inside the Hook: ```js {9-11} @@ -1072,8 +1064,8 @@ export function showNotification(message, theme = 'dark') { ```json package.json hidden { "dependencies": { - "react": "canary", - "react-dom": "canary", + "react": "latest", + "react-dom": "latest", "react-scripts": "latest", "toastify-js": "1.12.0" }, @@ -1718,22 +1710,6 @@ html, body { min-height: 300px; } } ``` -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - However, you didn't *have to* do that. As with regular functions, ultimately you decide where to draw the boundaries between different parts of your code. You could also take a very different approach. Instead of keeping the logic in the Effect, you could move most of the imperative logic inside a JavaScript [class:](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes) @@ -2207,22 +2183,6 @@ It looks like your `useInterval` Hook accepts an event listener as an argument. -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useCounter } from './useCounter.js'; import { useInterval } from './useInterval.js'; @@ -2278,22 +2238,6 @@ With this change, both intervals work as expected and don't interfere with each -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useCounter } from './useCounter.js'; diff --git a/src/content/learn/separating-events-from-effects.md b/src/content/learn/separating-events-from-effects.md index 2a19e0f13..7903cb363 100644 --- a/src/content/learn/separating-events-from-effects.md +++ b/src/content/learn/separating-events-from-effects.md @@ -400,14 +400,6 @@ You need a way to separate this non-reactive logic from the reactive Effect arou ### Declaring an Effect Event {/*declaring-an-effect-event*/} - - -**The `useEffectEvent` API is currently only available in React’s Canary and Experimental channels.** - -[Learn more about React’s release channels here.](/community/versioning-policy#all-release-channels) - - - Use a special Hook called [`useEffectEvent`](/reference/react/useEffectEvent) to extract this non-reactive logic out of your Effect: ```js {1,4-6} @@ -450,8 +442,8 @@ Verify that the new behavior works as you would expect: ```json package.json hidden { "dependencies": { - "react": "canary", - "react-dom": "canary", + "react": "latest", + "react-dom": "latest", "react-scripts": "latest", "toastify-js": "1.12.0" }, @@ -580,14 +572,6 @@ You can think of Effect Events as being very similar to event handlers. The main ### Reading latest props and state with Effect Events {/*reading-latest-props-and-state-with-effect-events*/} - - -**The `useEffectEvent` API is currently only available in React’s Canary and Experimental channels.** - -[Learn more about React’s release channels here.](/community/versioning-policy#all-release-channels) - - - Effect Events let you fix many patterns where you might be tempted to suppress the dependency linter. For example, say you have an Effect to log the page visits: @@ -729,7 +713,7 @@ function Page({ url }) { } ``` -After `useEffectEvent` becomes a stable part of React, we recommend **never suppressing the linter**. +We recommend **never suppressing the linter**. The first downside of suppressing the rule is that React will no longer warn you when your Effect needs to "react" to a new reactive dependency you've introduced to your code. In the earlier example, you added `url` to the dependencies *because* React reminded you to do it. You will no longer get such reminders for any future edits to that Effect if you disable the linter. This leads to bugs. @@ -804,22 +788,6 @@ With `useEffectEvent`, there is no need to "lie" to the linter, and the code wor -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useState, useEffect } from 'react'; import { useEffectEvent } from 'react'; @@ -882,14 +850,6 @@ Read [Removing Effect Dependencies](/learn/removing-effect-dependencies) for oth ### Limitations of Effect Events {/*limitations-of-effect-events*/} - - -**The `useEffectEvent` API is currently only available in React’s Canary and Experimental channels.** - -[Learn more about React’s release channels here.](/community/versioning-policy#all-release-channels) - - - Effect Events are very limited in how you can use them: * **Only call them from inside Effects.** @@ -979,23 +939,6 @@ To fix this code, it's enough to follow the rules. -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - - ```js {expectedErrors: {'react-compiler': [14]}} import { useState, useEffect } from 'react'; @@ -1049,22 +992,6 @@ If you remove the suppression comment, React will tell you that this Effect's co -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useState, useEffect } from 'react'; @@ -1127,22 +1054,6 @@ It seems like the Effect which sets up the timer "reacts" to the `increment` val -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useState, useEffect } from 'react'; import { useEffectEvent } from 'react'; @@ -1196,22 +1107,6 @@ To solve the issue, extract an `onTick` Effect Event from the Effect: -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useState, useEffect } from 'react'; import { useEffectEvent } from 'react'; @@ -1278,22 +1173,6 @@ Code inside Effect Events is not reactive. Are there cases in which you would _w -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useState, useEffect } from 'react'; import { useEffectEvent } from 'react'; @@ -1365,22 +1244,6 @@ The problem with the above example is that it extracted an Effect Event called ` -```json package.json hidden -{ - "dependencies": { - "react": "canary", - "react-dom": "canary", - "react-scripts": "latest" - }, - "scripts": { - "start": "react-scripts start", - "build": "react-scripts build", - "test": "react-scripts test --env=jsdom", - "eject": "react-scripts eject" - } -} -``` - ```js import { useState, useEffect } from 'react'; import { useEffectEvent } from 'react'; @@ -1464,8 +1327,8 @@ Your Effect knows which room it connected to. Is there any information that you ```json package.json hidden { "dependencies": { - "react": "canary", - "react-dom": "canary", + "react": "latest", + "react-dom": "latest", "react-scripts": "latest", "toastify-js": "1.12.0" }, @@ -1605,8 +1468,8 @@ To fix the issue, instead of reading the *latest* `roomId` inside the Effect Eve ```json package.json hidden { "dependencies": { - "react": "canary", - "react-dom": "canary", + "react": "latest", + "react-dom": "latest", "react-scripts": "latest", "toastify-js": "1.12.0" }, @@ -1742,8 +1605,8 @@ To solve the additional challenge, save the notification timeout ID and clear it ```json package.json hidden { "dependencies": { - "react": "canary", - "react-dom": "canary", + "react": "latest", + "react-dom": "latest", "react-scripts": "latest", "toastify-js": "1.12.0" }, diff --git a/src/content/learn/tutorial-tic-tac-toe.md b/src/content/learn/tutorial-tic-tac-toe.md index f25754bee..98fd132e2 100644 --- a/src/content/learn/tutorial-tic-tac-toe.md +++ b/src/content/learn/tutorial-tic-tac-toe.md @@ -283,15 +283,17 @@ Katika CodeSandbox utaona sehemu tatu kuu: ![CodeSandbox na msimbo wa mwanzo](../images/tutorial/react-starter-code-codesandbox.png) +<<<<<<< HEAD <<<<<<< HEAD 1. Sehemu ya _Files_ na orodha ya mafaili kama `App.js`, `index.js`, `styles.css` na folda inayoitwa `public` 1. _Kihariri cha msimbo_ ambapo utaona msimbo wa chanzo wa faili uliyouchagua 1. Sehemu ya _kivinjari_ ambapo utaona jinsi msimbo ulioandika utakavyonyeshwa ======= +======= 1. The _Files_ section with a list of files like `App.js`, `index.js`, `styles.css` in `src` folder and a folder called `public` 1. The _code editor_ where you'll see the source code of your selected file 1. The _browser_ section where you'll see how the code you've written will be displayed ->>>>>>> 49c2d26722fb1b5865ce0221a4cadc71b615e4cf +>>>>>>> 11cb6b591571caf5fa2a192117b6a6445c3f2027 Faili ya `App.js` inapaswa kuchaguliwa katika sehemu ya _Files_. Maudhui ya faili hiyo katika _mhariri wa msimbo_ yanapaswa kuwa: @@ -2253,11 +2255,13 @@ body { +<<<<<<< HEAD <<<<<<< HEAD Unapozunguka kupitia orodha ya `history` ndani ya function unayopitisha kwa `map`, hoja ya `squares` inapitia kila kipengele cha `history`, na hoja ya `move` inapitia kila kiashiria cha orodha: `0`, `1`, `2`, …. (Katika hali nyingi, ungehitaji vipengele halisi vya orodha, lakini ili kuonyesha orodha ya harakati utahitaji tu viashiria.) ======= +======= As you iterate through the `history` array inside the function you passed to `map`, the `squares` argument goes through each element of `history`, and the `move` argument goes through each array index: `0`, `1`, `2`, …. (In most cases, you'd need the actual array elements, but to render a list of moves you will only need indexes.) ->>>>>>> 49c2d26722fb1b5865ce0221a4cadc71b615e4cf +>>>>>>> 11cb6b591571caf5fa2a192117b6a6445c3f2027 Kwa kila harakati katika historia ya mchezo wa tic-tac-toe, unaunda kipengele cha orodha `
  • ` kinachojumuisha kitufe ` + + ); +} + +function Shell({ children }) { + // In a real app, this is where you would put your html and body. + // We're just using tags here we can include in an existing body for demonstration purposes + return ( + + {children} + + ); +} + +function App() { + return ( + + +
    + + +
    + + + ); +} + +async function main(frame) { + // Layer 1 + const controller = new AbortController(); + const prerenderedApp = prerender(, { + signal: controller.signal, + onError(error) { + if (error instanceof Postponed) { + } else { + console.error(error); + } + }, + }); + // We're immediately aborting in a macrotask. + // Any data fetching that's not available synchronously, or in a microtask, will not have finished. + setTimeout(() => { + controller.abort(new Postponed()); + }); + + const { prelude, postponed } = await prerenderedApp; + await flushReadableStreamToFrame(prelude, frame); + + // Layer 2 + // Just waiting here for demonstration purposes. + // In a real app, the prelude and postponed state would've been serialized in Layer 1 and Layer would deserialize them. + // The prelude content could be flushed immediated as plain HTML while + // React is continuing to render from where the prerender left off. + await sleep(2000); + + // You would get the cookies from the incoming HTTP request + resolveCookies({ sessionID: "abc" }); + + const stream = await resume(, postponed); + + await flushReadableStreamToFrame(stream, frame); + + // Layer 3 + // Just waiting here for demonstration purposes. + await sleep(2000); + + hydrateRoot(frame.contentWindow.document, ); +} + +main(document.getElementById("container")); + +``` + +```js src/demo-helpers.js +export async function flushReadableStreamToFrame(readable, frame) { + const document = frame.contentWindow.document; + const decoder = new TextDecoder(); + for await (const chunk of readable) { + const partialHTML = decoder.decode(chunk); + document.write(partialHTML); + } +} + +// This doesn't need to be an error. +// You can use any other means to check if an error during prerender was +// from an intentional abort or a real error. +export class Postponed extends Error {} + +// We're just hardcoding a session here. +export function getUser(sessionID) { + return { + name: "Alice", + }; +} + +export function sleep(timeoutMS) { + return new Promise((resolve) => { + setTimeout(() => { + resolve(); + }, timeoutMS); + }); +} +``` + + + +### Further reading {/*further-reading*/} + +Resuming behaves like `renderToReadableStream`. For more examples, check out the [usage section of `renderToReadableStream`](/reference/react-dom/server/renderToReadableStream#usage). +The [usage section of `prerender`](/reference/react-dom/static/prerender#usage) includes examples of how to use `prerender` specifically. \ No newline at end of file diff --git a/src/content/reference/react-dom/server/resumeToPipeableStream.md b/src/content/reference/react-dom/server/resumeToPipeableStream.md new file mode 100644 index 000000000..48caa3be6 --- /dev/null +++ b/src/content/reference/react-dom/server/resumeToPipeableStream.md @@ -0,0 +1,78 @@ +--- +title: resumeToPipeableStream +--- + + + +`resumeToPipeableStream` streams a pre-rendered React tree to a pipeable [Node.js Stream.](https://nodejs.org/api/stream.html) + +```js +const {pipe, abort} = await resumeToPipeableStream(reactNode, postponedState, options?) +``` + + + + + + + +This API is specific to Node.js. Environments with [Web Streams,](https://developer.mozilla.org/en-US/docs/Web/API/Streams_API) like Deno and modern edge runtimes, should use [`resume`](/reference/react-dom/server/renderToReadableStream) instead. + + + +--- + +## Reference {/*reference*/} + +### `resumeToPipeableStream(node, postponed, options?)` {/*resume-to-pipeable-stream*/} + +Call `resume` to resume rendering a pre-rendered React tree as HTML into a [Node.js Stream.](https://nodejs.org/api/stream.html#writable-streams) + +```js +import { resume } from 'react-dom/server'; +import {getPostponedState} from './storage'; + +async function handler(request, response) { + const postponed = await getPostponedState(request); + const {pipe} = resumeToPipeableStream(, postponed, { + onShellReady: () => { + pipe(response); + } + }); +} +``` + +[See more examples below.](#usage) + +#### Parameters {/*parameters*/} + +* `reactNode`: The React node you called `prerender` with. For example, a JSX element like ``. It is expected to represent the entire document, so the `App` component should render the `` tag. +* `postponedState`: The opaque `postpone` object returned from a [prerender API](/reference/react-dom/static/index), loaded from wherever you stored it (e.g. redis, a file, or S3). +* **optional** `options`: An object with streaming options. + * **optional** `nonce`: A [`nonce`](http://developer.mozilla.org/en-US/docs/Web/HTML/Element/script#nonce) string to allow scripts for [`script-src` Content-Security-Policy](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/script-src). + * **optional** `signal`: An [abort signal](https://developer.mozilla.org/en-US/docs/Web/API/AbortSignal) that lets you [abort server rendering](#aborting-server-rendering) and render the rest on the client. + * **optional** `onError`: A callback that fires whenever there is a server error, whether [recoverable](/reference/react-dom/server/renderToReadableStream#recovering-from-errors-outside-the-shell) or [not.](/reference/react-dom/server/renderToReadableStream#recovering-from-errors-inside-the-shell) By default, this only calls `console.error`. If you override it to [log crash reports,](/reference/react-dom/server/renderToReadableStream#logging-crashes-on-the-server) make sure that you still call `console.error`. + * **optional** `onShellReady`: A callback that fires right after the [shell](#specifying-what-goes-into-the-shell) has finished. You can call `pipe` here to start streaming. React will [stream the additional content](#streaming-more-content-as-it-loads) after the shell along with the inline `