mirror of
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7699cbe9df
* Using developit/unfetch as the Fetch API polyfill * Added a stateless component with getInitialProps in the readme. * Fixed typo
847 lines
28 KiB
Markdown
847 lines
28 KiB
Markdown
<img width="112" alt="screen shot 2016-10-25 at 2 37 27 pm" src="https://cloud.githubusercontent.com/assets/13041/19686250/971bf7f8-9ac0-11e6-975c-188defd82df1.png">
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[![Build Status](https://travis-ci.org/zeit/next.js.svg?branch=master)](https://travis-ci.org/zeit/next.js)
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[![Coverage Status](https://coveralls.io/repos/zeit/next.js/badge.svg?branch=master)](https://coveralls.io/r/zeit/next.js?branch=master)
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[![Slack Channel](https://zeit-slackin.now.sh/badge.svg)](https://zeit.chat)
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Next.js is a minimalistic framework for server-rendered React applications.
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<!-- START doctoc generated TOC please keep comment here to allow auto update -->
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<!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
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<!-- https://github.com/thlorenz/doctoc -->
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- [How to use](#how-to-use)
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- [Setup](#setup)
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- [Automatic code splitting](#automatic-code-splitting)
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- [CSS](#css)
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- [Built-in CSS support](#built-in-css-support)
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- [CSS-in-JS](#css-in-js)
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- [Static file serving (e.g.: images)](#static-file-serving-eg-images)
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- [Populating `<head>`](#populating-head)
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- [Fetching data and component lifecycle](#fetching-data-and-component-lifecycle)
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- [Routing](#routing)
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- [With `<Link>`](#with-link)
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- [Imperatively](#imperatively)
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- [Router Events](#router-events)
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- [Shallow Routing](#shallow-routing)
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- [Prefetching Pages](#prefetching-pages)
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- [With `<Link>`](#with-link-1)
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- [Imperatively](#imperatively-1)
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- [Custom server and routing](#custom-server-and-routing)
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- [Custom `<Document>`](#custom-document)
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- [Custom error handling](#custom-error-handling)
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- [Custom configuration](#custom-configuration)
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- [Customizing webpack config](#customizing-webpack-config)
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- [Customizing babel config](#customizing-babel-config)
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- [Production deployment](#production-deployment)
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- [FAQ](#faq)
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- [Roadmap](#roadmap)
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- [Contributing](#contributing)
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- [Authors](#authors)
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<!-- END doctoc generated TOC please keep comment here to allow auto update -->
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## How to use
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### Setup
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Install it:
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```bash
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npm install next react react-dom --save
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```
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and add a script to your package.json like this:
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```json
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{
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"scripts": {
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"dev": "next",
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"build": "next build",
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"start": "next start"
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}
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}
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```
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After that, the file-system is the main API. Every `.js` file becomes a route that gets automatically processed and rendered.
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Populate `./pages/index.js` inside your project:
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```jsx
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export default () => (
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<div>Welcome to next.js!</div>
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)
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```
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and then just run `npm run dev` and go to `http://localhost:3000`. To use another port, you can run `npm run dev -- -p <your port here>`.
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So far, we get:
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- Automatic transpilation and bundling (with webpack and babel)
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- Hot code reloading
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- Server rendering and indexing of `./pages`
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- Static file serving. `./static/` is mapped to `/static/`
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To see how simple this is, check out the [sample app - nextgram](https://github.com/zeit/nextgram)
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### Automatic code splitting
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Every `import` you declare gets bundled and served with each page. That means pages never load unnecessary code!
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```jsx
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import cowsay from 'cowsay-browser'
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export default () => (
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<pre>{ cowsay.say({ text: 'hi there!' }) }</pre>
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)
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```
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### CSS
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#### Built-in CSS support
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<p><details>
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<summary><b>Examples</b></summary>
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<ul><li><a href="./examples/basic-css">Basic css</a></li></ul>
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</details></p>
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We bundle [styled-jsx](https://github.com/zeit/styled-jsx) to provide support for isolated scoped CSS. The aim is to support "shadow CSS" resembling of Web Components, which unfortunately [do not support server-rendering and are JS-only](https://github.com/w3c/webcomponents/issues/71).
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```jsx
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export default () => (
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<div>
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Hello world
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<p>scoped!</p>
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<style jsx>{`
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p {
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color: blue;
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}
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div {
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background: red;
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}
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@media (max-width: 600px) {
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div {
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background: blue;
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}
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}
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`}</style>
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</div>
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)
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```
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#### CSS-in-JS
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<p><details>
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<summary>
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<b>Examples</b>
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</summary>
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<ul><li><a href="./examples/with-styled-components">Styled components</a></li><li><a href="./examples/with-styletron">Styletron</a></li><li><a href="./examples/with-glamor">Glamor</a></li><li><a href="./examples/with-cxs">Cxs</a></li><li><a href="./examples/with-aphrodite">Aphrodite</a></li><li><a href="./examples/with-fela">Fela</a></li></ul>
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</details></p>
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It's possible to use any existing CSS-in-JS solution. The simplest one is inline styles:
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```jsx
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export default () => (
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<p style={{ color: 'red' }}>hi there</p>
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)
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```
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To use more sophisticated CSS-in-JS solutions, you typically have to implement style flushing for server-side rendering. We enable this by allowing you to define your own [custom `<Document>`](#user-content-custom-document) component that wraps each page
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### Static file serving (e.g.: images)
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Create a folder called `static` in your project root directory. From your code you can then reference those files with `/static/` URLs:
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```jsx
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export default () => (
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<img src="/static/my-image.png" />
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)
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```
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### Populating `<head>`
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<p><details>
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<summary><b>Examples</b></summary>
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<ul>
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<li><a href="./examples/head-elements">Head elements</a></li>
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<li><a href="./examples/layout-component">Layout component</a></li>
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</ul>
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</details></p>
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We expose a built-in component for appending elements to the `<head>` of the page.
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```jsx
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import Head from 'next/head'
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export default () => (
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<div>
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<Head>
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<title>My page title</title>
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<meta name="viewport" content="initial-scale=1.0, width=device-width" />
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</Head>
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<p>Hello world!</p>
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</div>
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)
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```
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_Note: The contents of `<head>` get cleared upon unmounting the component, so make sure each page completely defines what it needs in `<head>`, without making assumptions about what other pages added_
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### Fetching data and component lifecycle
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<p><details>
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<summary><b>Examples</b></summary>
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<ul><li><a href="./examples/data-fetch">Data fetch</a></li></ul>
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</details></p>
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When you need state, lifecycle hooks or **initial data population** you can export a `React.Component` (instead of a stateless function, like shown above):
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```jsx
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import React from 'react'
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export default class extends React.Component {
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static async getInitialProps ({ req }) {
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return req
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? { userAgent: req.headers['user-agent'] }
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: { userAgent: navigator.userAgent }
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}
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render () {
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return <div>
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Hello World {this.props.userAgent}
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</div>
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}
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}
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```
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Notice that to load data when the page loads, we use `getInitialProps` which is an [`async`](https://zeit.co/blog/async-and-await) static method. It can asynchronously fetch anything that resolves to a JavaScript plain `Object`, which populates `props`.
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For the initial page load, `getInitialProps` will execute on the server only. `getInitialProps` will only be executed on the client when navigating to a different route via the `Link` component or using the routing APIs.
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_Note: `getInitialProps` can **not** be used in children components. Only in `pages`._
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You can also define the `getInitialProps` lifecycle method for stateless components:
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```jsx
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const Page = ({ stars }) => <div>Next stars: {stars}</div>
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Page.getInitialProps = async ({ req }) => {
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const res = await fetch('https://api.github.com/repos/zeit/next.js')
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const json = await res.json()
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return { stars: json.stargazers_count }
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}
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export default Page
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```
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`getInitialProps` receives a context object with the following properties:
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- `pathname` - path section of URL
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- `query` - query string section of URL parsed as an object
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- `req` - HTTP request object (server only)
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- `res` - HTTP response object (server only)
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- `jsonPageRes` - [Fetch Response](https://developer.mozilla.org/en-US/docs/Web/API/Response) object (client only)
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- `err` - Error object if any error is encountered during the rendering
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### Routing
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#### With `<Link>`
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<p><details>
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<summary><b>Examples</b></summary>
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<ul>
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<li><a href="./examples/hello-world">Hello World</a></li>
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</ul>
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</details></p>
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Client-side transitions between routes can be enabled via a `<Link>` component. Consider these two pages:
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```jsx
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// pages/index.js
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import Link from 'next/link'
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export default () => (
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<div>Click <Link href="/about"><a>here</a></Link> to read more</div>
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)
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```
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```jsx
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// pages/about.js
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export default () => (
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<p>Welcome to About!</p>
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)
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```
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__Note: use [`<Link prefetch>`](#prefetching-pages) for maximum performance, to link and prefetch in the background at the same time__
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Client-side routing behaves exactly like the browser:
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1. The component is fetched
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2. If it defines `getInitialProps`, data is fetched. If an error occurs, `_error.js` is rendered
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3. After 1 and 2 complete, `pushState` is performed and the new component rendered
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Each top-level component receives a `url` property with the following API:
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- `pathname` - `String` of the current path excluding the query string
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- `query` - `Object` with the parsed query string. Defaults to `{}`
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- `push(url, as=url)` - performs a `pushState` call with the given url
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- `replace(url, as=url)` - performs a `replaceState` call with the given url
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The second `as` parameter for `push` and `replace` is an optional _decoration_ of the URL. Useful if you configured custom routes on the server.
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##### With URL object
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<p><details>
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<summary><b>Examples</b></summary>
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<ul>
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<li><a href="./examples/with-url-object-routing">With URL Object Routing</a></li>
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</ul>
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</details></p>
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The component `<Link>` can also receive an URL object and it will automatically format it to create the URL string.
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```jsx
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// pages/index.js
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import Link from 'next/link'
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export default () => (
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<div>Click <Link href={{ pathname: 'about', query: { name: 'Zeit' }}}<a>here</a></Link> to read more</div>
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)
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```
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That will generate the URL string `/about?name=Zeit`, you can use every property as defined in the [Node.js URL module documentation](https://nodejs.org/api/url.html#url_url_strings_and_url_objects).
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The default behaviour for the `<Link>` component is to `push` a new url into the stack. You can use the `replace` prop to prevent adding a new entry.
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```jsx
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// pages/index.js
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import Link from 'next/link'
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export default () => (
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<div>Click <Link href='/about' replace><a>here</a></Link> to read more</div>
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)
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```
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#### Imperatively
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<p><details>
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<summary><b>Examples</b></summary>
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<ul>
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<li><a href="./examples/using-router">Basic routing</a></li>
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<li><a href="./examples/with-loading">With a page loading indicator</a></li>
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</ul>
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</details></p>
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You can also do client-side page transitions using the `next/router`
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```jsx
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import Router from 'next/router'
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export default () => (
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<div>Click <span onClick={() => Router.push('/about')}>here</span> to read more</div>
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)
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```
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Above `Router` object comes with the following API:
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- `route` - `String` of the current route
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- `pathname` - `String` of the current path excluding the query string
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- `query` - `Object` with the parsed query string. Defaults to `{}`
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- `push(url, as=url)` - performs a `pushState` call with the given url
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- `replace(url, as=url)` - performs a `replaceState` call with the given url
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The second `as` parameter for `push` and `replace` is an optional _decoration_ of the URL. Useful if you configured custom routes on the server.
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_Note: in order to programmatically change the route without triggering navigation and component-fetching, use `props.url.push` and `props.url.replace` within a component_
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##### With URL object
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You can use an URL object the same way you use it in a `<Link>` component to `push` and `replace` an url.
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```jsx
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import Router from 'next/router'
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const handler = () => Router.push({
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pathname: 'about',
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query: { name: 'Zeit' }
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})
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export default () => (
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<div>Click <span onClick={handler}>here</span> to read more</div>
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)
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```
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This uses of the same exact parameters as in the `<Link>` component.
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##### Router Events
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You can also listen to different events happening inside the Router.
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Here's a list of supported events:
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- `routeChangeStart(url)` - Fires when a route starts to change
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- `routeChangeComplete(url)` - Fires when a route changed completely
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- `routeChangeError(err, url)` - Fires when there's an error when changing routes
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- `beforeHistoryChange(url)` - Fires just before changing the browser's history
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- `appUpdated(nextRoute)` - Fires when switching pages and there's a new version of the app
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> Here `url` is the URL shown in the browser. If you call `Router.push(url, as)` (or similar), then the value of `url` will be `as`.
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Here's how to properly listen to the router event `routeChangeStart`:
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```js
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Router.onRouteChangeStart = (url) => {
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console.log('App is changing to: ', url)
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}
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```
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If you are no longer want to listen to that event, you can simply unset the event listener like this:
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```js
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Router.onRouteChangeStart = null
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```
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If a route load is cancelled (for example by clicking two links rapidly in succession), `routeChangeError` will fire. The passed `err` will contained a `cancelled` property set to `true`.
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```js
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Router.onRouteChangeError = (err, url) => {
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if (err.cancelled) {
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console.log(`Route to ${url} was cancelled!`)
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}
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}
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```
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If you change a route while in between a new deployment, we can't navigate the app via client side. We need to do a full browser navigation. We do it automatically for you.
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But you can customize that via `Route.onAppUpdated` event like this:
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```js
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Router.onAppUpdated = (nextUrl) => {
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// persist the local state
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location.href = nextUrl
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}
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```
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##### Shallow Routing
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<p><details>
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<summary><b>Examples</b></summary>
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<ul>
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<li><a href="./examples/with-shallow-routing">Shallow Routing</a></li>
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</ul>
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</details></p>
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Shallow routing allows you to change the URL without running `getInitialProps`. You'll receive the updated `pathname` and the `query` via the `url` prop of the same page that's loaded, without losing state.
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You can do this by invoking the eith `Router.push` or `Router.replace` with `shallow: true` option. Here's an example:
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|
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```jsx
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// Current URL is "/"
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const href = '/?counter=10'
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const as = href
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Router.push(href, as, { shallow: true })
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```
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Now, the URL is updated to `/?counter=10`. You can see the updated URL with `this.props.url` inside the `Component`.
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You can watch for URL changes via [`componentWillReceiveProps`](https://facebook.github.io/react/docs/react-component.html#componentwillreceiveprops) hook as shown below:
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```jsx
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componentWillReceiveProps(nextProps) {
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const { pathname, query } = nextProps.url
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// fetch data based on the new query
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}
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```
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> NOTES:
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>
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> Shallow routing works **only** for same page URL changes. For an example, let's assume we've another page called `about`, and you run this:
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> ```js
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> Router.push('/about?counter=10', '/about?counter=10', { shallow: true })
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> ```
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> Since that's a new page, it'll unload the current page, load the new one and call `getInitialProps` even we asked to do shallow routing.
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### Prefetching Pages
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(This is a production only feature)
|
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|
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<p><details>
|
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<summary><b>Examples</b></summary>
|
||
<ul><li><a href="./examples/with-prefetching">Prefetching</a></li></ul>
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</details></p>
|
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|
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Next.js has an API which allows you to prefetch pages.
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Since Next.js server-renders your pages, this allows all the future interaction paths of your app to be instant. Effectively Next.js gives you the great initial download performance of a _website_, with the ahead-of-time download capabilities of an _app_. [Read more](https://zeit.co/blog/next#anticipation-is-the-key-to-performance).
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> With prefetching Next.js only download JS code. When the page is getting rendered, you may need to wait for the data.
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#### With `<Link>`
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You can add `prefetch` prop to any `<Link>` and Next.js will prefetch those pages in the background.
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```jsx
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import Link from 'next/link'
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|
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// example header component
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export default () => (
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<nav>
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<ul>
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<li><Link prefetch href='/'><a>Home</a></Link></li>
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<li><Link prefetch href='/about'><a>About</a></Link></li>
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<li><Link prefetch href='/contact'><a>Contact</a></Link></li>
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</ul>
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</nav>
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)
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```
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|
||
#### Imperatively
|
||
|
||
Most prefetching needs are addressed by `<Link />`, but we also expose an imperative API for advanced usage:
|
||
|
||
```jsx
|
||
import Router from 'next/router'
|
||
export default ({ url }) => (
|
||
<div>
|
||
<a onClick={ () => setTimeout(() => url.pushTo('/dynamic'), 100) }>
|
||
A route transition will happen after 100ms
|
||
</a>
|
||
{
|
||
// but we can prefetch it!
|
||
Router.prefetch('/dynamic')
|
||
}
|
||
</div>
|
||
)
|
||
```
|
||
|
||
### Custom server and routing
|
||
|
||
<p><details>
|
||
<summary><b>Examples</b></summary>
|
||
<ul>
|
||
<li><a href="./examples/custom-server">Basic custom server</a></li>
|
||
<li><a href="./examples/custom-server-express">Express integration</a></li>
|
||
<li><a href="./examples/custom-server-hapi">Hapi integration</a></li>
|
||
<li><a href="./examples/custom-server-koa">Koa integration</a></li>
|
||
<li><a href="./examples/parameterized-routing">Parameterized routing</a></li>
|
||
<li><a href="./examples/ssr-caching">SSR caching</a></li>
|
||
</ul>
|
||
</details></p>
|
||
|
||
Typically you start your next server with `next start`. It's possible, however, to start a server 100% programmatically in order to customize routes, use route patterns, etc
|
||
|
||
This example makes `/a` resolve to `./pages/b`, and `/b` resolve to `./pages/a`:
|
||
|
||
```js
|
||
const { createServer } = require('http')
|
||
const { parse } = require('url')
|
||
const next = require('next')
|
||
|
||
const dev = process.env.NODE_ENV !== 'production'
|
||
const app = next({ dev })
|
||
const handle = app.getRequestHandler()
|
||
|
||
app.prepare().then(() => {
|
||
createServer((req, res) => {
|
||
// Be sure to pass `true` as the second argument to `url.parse`.
|
||
// This tells it to parse the query portion of the URL.
|
||
const parsedUrl = parse(req.url, true)
|
||
const { pathname, query } = parsedUrl
|
||
|
||
if (pathname === '/a') {
|
||
app.render(req, res, '/b', query)
|
||
} else if (pathname === '/b') {
|
||
app.render(req, res, '/a', query)
|
||
} else {
|
||
handle(req, res, parsedUrl)
|
||
}
|
||
})
|
||
.listen(3000, (err) => {
|
||
if (err) throw err
|
||
console.log('> Ready on http://localhost:3000')
|
||
})
|
||
})
|
||
```
|
||
|
||
The `next` API is as follows:
|
||
- `next(path: string, opts: object)` - `path` is where the Next project is located
|
||
- `next(opts: object)`
|
||
|
||
Supported options:
|
||
- `dev` (`bool`) whether to launch Next.js in dev mode - default `false`
|
||
- `dir` (`string`) where the Next project is located - default `'.'`
|
||
- `quiet` (`bool`) Hide error messages containing server information - default `false`
|
||
|
||
Then, change your `start` script to `NODE_ENV=production node server.js`.
|
||
|
||
### Custom `<Document>`
|
||
|
||
<p><details>
|
||
<summary><b>Examples</b></summary>
|
||
<ul><li><a href="./examples/with-styled-components">Styled components custom document</a></li></ul>
|
||
<ul><li><a href="./examples/with-amp">Google AMP</a></li></ul>
|
||
</details></p>
|
||
|
||
Pages in `Next.js` skip the definition of the surrounding document's markup. For example, you never include `<html>`, `<body>`, etc. To override that default behavior, you must create a file at `./pages/_document.js`, where you can extend the `Document` class:
|
||
|
||
```jsx
|
||
// ./pages/_document.js
|
||
import Document, { Head, Main, NextScript } from 'next/document'
|
||
import flush from 'styled-jsx/server'
|
||
|
||
export default class MyDocument extends Document {
|
||
static getInitialProps ({ renderPage }) {
|
||
const {html, head} = renderPage()
|
||
const styles = flush()
|
||
return { html, head, styles }
|
||
}
|
||
|
||
render () {
|
||
return (
|
||
<html>
|
||
<Head>
|
||
<style>{`body { margin: 0 } /* custom! */`}</style>
|
||
</Head>
|
||
<body className="custom_class">
|
||
{this.props.customValue}
|
||
<Main />
|
||
<NextScript />
|
||
</body>
|
||
</html>
|
||
)
|
||
}
|
||
}
|
||
```
|
||
|
||
The `ctx` object is equivalent to the one received in all [`getInitialProps`](#fetching-data-and-component-lifecycle) hooks, with one addition:
|
||
|
||
- `renderPage` (`Function`) a callback that executes the actual React rendering logic (synchronously). It's useful to decorate this function in order to support server-rendering wrappers like Aphrodite's [`renderStatic`](https://github.com/Khan/aphrodite#server-side-rendering)
|
||
|
||
### Custom error handling
|
||
|
||
404 or 500 errors are handled both client and server side by a default component `error.js`. If you wish to override it, define a `_error.js`:
|
||
|
||
```jsx
|
||
import React from 'react'
|
||
export default class Error extends React.Component {
|
||
static getInitialProps ({ res, jsonPageRes }) {
|
||
const statusCode = res ? res.statusCode : (jsonPageRes ? jsonPageRes.status : null)
|
||
return { statusCode }
|
||
}
|
||
|
||
render () {
|
||
return (
|
||
<p>{
|
||
this.props.statusCode
|
||
? `An error ${this.props.statusCode} occurred on server`
|
||
: 'An error occurred on client'
|
||
}</p>
|
||
)
|
||
}
|
||
}
|
||
```
|
||
|
||
### Custom configuration
|
||
|
||
For custom advanced behavior of Next.js, you can create a `next.config.js` in the root of your project directory (next to `pages/` and `package.json`).
|
||
|
||
Note: `next.config.js` is a regular Node.js module, not a JSON file. It gets used by the Next server and build phases, and not included in the browser build.
|
||
|
||
```javascript
|
||
// next.config.js
|
||
module.exports = {
|
||
/* config options here */
|
||
}
|
||
```
|
||
|
||
### Customizing webpack config
|
||
|
||
In order to extend our usage of `webpack`, you can define a function that extends its config via `next.config.js`.
|
||
|
||
```js
|
||
// This file is not going through babel transformation.
|
||
// So, we write it in vanilla JS
|
||
// (But you could use ES2015 features supported by your Node.js version)
|
||
|
||
module.exports = {
|
||
webpack: (config, { dev }) => {
|
||
// Perform customizations to config
|
||
|
||
// Important: return the modified config
|
||
return config
|
||
}
|
||
}
|
||
```
|
||
|
||
*Warning: Adding loaders to support new file types (css, less, svg, etc.) is __not__ recommended because only the client code gets bundled via webpack and thus it won't work on the initial server rendering. Babel plugins are a good alternative because they're applied consistently between server/client rendering (e.g. [babel-plugin-inline-react-svg](https://github.com/kesne/babel-plugin-inline-react-svg)).*
|
||
|
||
### Customizing babel config
|
||
|
||
<p><details>
|
||
<summary><b>Examples</b></summary>
|
||
<ul><li><a href="./examples/with-custom-babel-config">Custom babel configuration</a></li></ul>
|
||
</details></p>
|
||
|
||
In order to extend our usage of `babel`, you can simply define a `.babelrc` file at the root of your app. This file is optional.
|
||
|
||
If found, we're going to consider it the *source of truth*, therefore it needs to define what next needs as well, which is the `next/babel` preset.
|
||
|
||
This is designed so that you are not surprised by modifications we could make to the babel configurations.
|
||
|
||
Here's an example `.babelrc` file:
|
||
|
||
```js
|
||
{
|
||
"presets": [
|
||
"next/babel",
|
||
"stage-0"
|
||
],
|
||
}
|
||
```
|
||
|
||
## Production deployment
|
||
|
||
To deploy, instead of running `next`, you want to build for production usage ahead of time. Therefore, building and starting are separate commands:
|
||
|
||
```bash
|
||
next build
|
||
next start
|
||
```
|
||
|
||
For example, to deploy with [`now`](https://zeit.co/now) a `package.json` like follows is recommended:
|
||
|
||
```json
|
||
{
|
||
"name": "my-app",
|
||
"dependencies": {
|
||
"next": "latest"
|
||
},
|
||
"scripts": {
|
||
"dev": "next",
|
||
"build": "next build",
|
||
"start": "next start"
|
||
}
|
||
}
|
||
```
|
||
|
||
Then run `now` and enjoy!
|
||
|
||
Next.js can be deployed to other hosting solutions too. Please have a look at the ['Deployment'](https://github.com/zeit/next.js/wiki/Deployment) section of the wiki.
|
||
|
||
Note: we recommend putting `.next` in `.npmignore` or `.gitignore`. Otherwise, use `files` or `now.files` to opt-into a whitelist of files you want to deploy (and obviously exclude `.next`)
|
||
|
||
## FAQ
|
||
|
||
<details>
|
||
<summary>Is this production ready?</summary>
|
||
Next.js has been powering https://zeit.co since its inception.
|
||
|
||
We’re ecstatic about both the developer experience and end-user performance, so we decided to share it with the community.
|
||
</details>
|
||
|
||
<details>
|
||
<summary>How big is it?</summary>
|
||
|
||
The client side bundle size should be measured in a per-app basis.
|
||
A small Next main bundle is around 65kb gzipped.
|
||
|
||
</details>
|
||
|
||
<details>
|
||
<summary>Is this like `create-react-app`?</summary>
|
||
|
||
Yes and No.
|
||
|
||
Yes in that both make your life easier.
|
||
|
||
No in that it enforces a _structure_ so that we can do more advanced things like:
|
||
- Server side rendering
|
||
- Automatic code splitting
|
||
|
||
In addition, Next.js provides two built-in features that are critical for every single website:
|
||
- Routing with lazy component loading: `<Link>` (by importing `next/link`)
|
||
- A way for components to alter `<head>`: `<Head>` (by importing `next/head`)
|
||
|
||
If you want to create re-usable React components that you can embed in your Next.js app or other React applications, using `create-react-app` is a great idea. You can later `import` it and keep your codebase clean!
|
||
|
||
</details>
|
||
|
||
<details>
|
||
<summary>How do I use CSS-in-JS solutions?</summary>
|
||
|
||
Next.js bundles [styled-jsx](https://github.com/zeit/styled-jsx) supporting scoped css. However you can use a CSS-in-JS solution in your Next app by just including your favorite library [as mentioned before](#css-in-js) in the document.
|
||
</details>
|
||
|
||
<details>
|
||
<summary>What syntactic features are transpiled? How do I change them?</summary>
|
||
|
||
We track V8. Since V8 has wide support for ES6 and `async` and `await`, we transpile those. Since V8 doesn’t support class decorators, we don’t transpile those.
|
||
|
||
See [this](https://github.com/zeit/next.js/blob/master/server/build/webpack.js#L79) and [this](https://github.com/zeit/next.js/issues/26)
|
||
|
||
</details>
|
||
|
||
<details>
|
||
<summary>Why a new Router?</summary>
|
||
|
||
Next.js is special in that:
|
||
|
||
- Routes don’t need to be known ahead of time
|
||
- Routes are always lazy-loadable
|
||
- Top-level components can define `getInitialProps` that should _block_ the loading of the route (either when server-rendering or lazy-loading)
|
||
|
||
As a result, we were able to introduce a very simple approach to routing that consists of two pieces:
|
||
|
||
- Every top level component receives a `url` object to inspect the url or perform modifications to the history
|
||
- A `<Link />` component is used to wrap elements like anchors (`<a/>`) to perform client-side transitions
|
||
|
||
We tested the flexibility of the routing with some interesting scenarios. For an example, check out [nextgram](https://github.com/zeit/nextgram).
|
||
|
||
</details>
|
||
|
||
<details>
|
||
<summary>How do I define a custom fancy route?</summary>
|
||
|
||
We [added](#custom-server-and-routing) the ability to map between an arbitrary URL and any component by supplying a request handler.
|
||
|
||
On the client side, we have a parameter call `as` on `<Link>` that _decorates_ the URL differently from the URL it _fetches_.
|
||
</details>
|
||
|
||
<details>
|
||
<summary>How do I fetch data?</summary>
|
||
|
||
It’s up to you. `getInitialProps` is an `async` function (or a regular function that returns a `Promise`). It can retrieve data from anywhere.
|
||
</details>
|
||
|
||
<details>
|
||
<summary>Can I use it with GraphQL?</summary>
|
||
|
||
Yes! Here's an example with [Apollo](./examples/with-apollo).
|
||
|
||
</details>
|
||
|
||
<details>
|
||
<summary>Can I use it with Redux?</summary>
|
||
|
||
Yes! Here's an [example](./examples/with-redux)
|
||
</details>
|
||
|
||
<details>
|
||
<summary>What is this inspired by?</summary>
|
||
|
||
Many of the goals we set out to accomplish were the ones listed in [The 7 principles of Rich Web Applications](http://rauchg.com/2014/7-principles-of-rich-web-applications/) by Guillermo Rauch.
|
||
|
||
The ease-of-use of PHP is a great inspiration. We feel Next.js is a suitable replacement for many scenarios where you otherwise would use PHP to output HTML.
|
||
|
||
Unlike PHP, we benefit from the ES6 module system and every file exports a **component or function** that can be easily imported for lazy evaluation or testing.
|
||
|
||
As we were researching options for server-rendering React that didn’t involve a large number of steps, we came across [react-page](https://github.com/facebookarchive/react-page) (now deprecated), a similar approach to Next.js by the creator of React Jordan Walke.
|
||
|
||
</details>
|
||
|
||
## Roadmap
|
||
|
||
Our Roadmap towards 2.0.0 [is public](https://github.com/zeit/next.js/wiki/Roadmap#nextjs-200).
|
||
|
||
## Contributing
|
||
|
||
Please see our [contributing.md](./contributing.md)
|
||
|
||
## Authors
|
||
|
||
- Naoyuki Kanezawa ([@nkzawa](https://twitter.com/nkzawa)) – ▲ZEIT
|
||
- Tony Kovanen ([@tonykovanen](https://twitter.com/tonykovanen)) – ▲ZEIT
|
||
- Guillermo Rauch ([@rauchg](https://twitter.com/rauchg)) – ▲ZEIT
|
||
- Dan Zajdband ([@impronunciable](https://twitter.com/impronunciable)) – Knight-Mozilla / Coral Project
|
||
- Tim Neutkens ([@timneutkens](https://github.com/timneutkens))
|