import crypto from 'crypto'
import Document, { Head, Main, NextScript } from 'next/document'
const cspHashOf = (text) => {
const hash = crypto.createHash('sha256')
hash.update(text)
return `'sha256-${hash.digest('base64')}'`
}
export default class MyDocument extends Document {
static async getInitialProps (ctx) {
let options
const enhanceComponent = Component => (props) => RENDERED
const enhanceApp = Component => (props) => RENDERED
if (ctx.query.withEnhancer) {
options = enhanceComponent
} else if (ctx.query.withEnhanceComponent || ctx.query.withEnhanceApp) {
options = {}
if (ctx.query.withEnhanceComponent) {
options.enhanceComponent = enhanceComponent
}
if (ctx.query.withEnhanceApp) {
options.enhanceApp = enhanceApp
}
}
const result = ctx.renderPage(options)
return { ...result, customProperty: 'Hello Document', withCSP: ctx.query.withCSP }
}
render () {
let csp
switch (this.props.withCSP) {
case 'hash':
csp = `default-src 'self'; script-src 'self' ${cspHashOf(NextScript.getInlineScriptSource(this.props))}; style-src 'self' 'unsafe-inline'`
break
case 'nonce':
csp = `default-src 'self'; script-src 'self' 'nonce-test-nonce'; style-src 'self' 'unsafe-inline'`
break
}
return (
{csp ? : null}
{this.props.customProperty}
Hello Document HMR
)
}
}