Next.js is a minimalistic framework for server-rendered React applications.
The file-system is the main API. Every .js file becomes a route that gets automatically processed and rendered.
Populate ./pages/index.js inside your project:
import React from 'react'
export default () => (
<div>Welcome to next.js!</div>
)and then just run next and go to http://localhost:3000
So far, we get:
- Automatic transpilation and bundling (with webpack and babel)
- Hot code reloading
- Server rendering and indexing of
./pages - Static file serving.
./static/is mapped to/static/
Every import you declare gets bundled and served with each page
import React from 'react'
import cowsay from 'cowsay'
export default () => (
<pre>{ cowsay('hi there!') }</pre>
)That means pages never load unneccessary code!
We use Aphrodite to provide a great built-in solution for CSS modularization
import React from 'react'
import { css, StyleSheet } from 'next/css'
export default () => {
<div className={ css(styles.main) }>
Hello world
</div>
})
const styles = StyleSheet.create({
main: {
background: 'red',
'@media (max-width: 600px)': {
background: 'blue'
}
}
})We expose a built-in component for appending elements to the <head> of the page.
import React from 'react'
import Head from 'next/head'
export default () => (
<Head>
<title>My page title</title>
<meta name="viewport" content="initial-scale=1.0, width=device-width" />
</Head>
<p>Hello world!</p>
)When state, lifecycle hooks or initial data population you can export a React.Component:
import React from 'react'
export default class extends React.Component {
async getInitialProps ({ isServer, req }) {
return isServer
? { userAgent: req.headers.userAgent }
: { userAgent: navigator.userAgent }
}
render () {
return <div>
Hello World {this.props.userAgent}
</div>
}
}Client-side transitions between routes are enabled via a <Link> component
import React from 'react'
import Link from 'next/link'
export default () => (
<div>Click <Link href="/about"><a>here</a></Link> to read more</div>
)import React from 'react'
export default () => (
<p>Welcome to About!</p>
)Client-side routing behaves exactly like the native UA:
- The component is fetched
- If it defines
getInitialProps, data is fetched. If an error occurs,_error.jsis rendered - After 1 and 2 complete,
pushStateis performed and the new component rendered
Each top-level component receives a url property with the following API:
path-Stringof the current path excluding the query stringquery-Objectwith the parsed query string. Defaults to{}push(url)- performs apushStatecall associated with the current componentreplace(url)- performs areplaceStatecall associated with the current componentpushTo(url)- performs apushStatecall that renders the newurl. This is equivalent to following a<Link>replaceTo(url)- performs areplaceStatecall that renders the newurl
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:
import React from 'react'
export default ({ statusCode }) => (
<p>An error { statusCode } occurred</p>
)To deploy, run:
next build
next startFor example, to deploy with now a package.json like follows is recommended:
{
"name": "my-app",
"dependencies": {
"next": "latest"
},
"scripts": {
"dev": "next",
"build": "next build",
"start": "next start"
}
}