(only in development) if (process.env.NODE_ENV !== 'production') { children = React.Children.map(children, (child) => { if (child && child.type === 'title') { console.warn("Warning: <title> should not be used in _document.js's <Head>. https://err.sh/next.js/no-document-title") } return child }) } return <head {...this.props}> {(head || []).map((h, i) => React.cloneElement(h, { key: h.key || i }))} {page !== '/_error' && <link rel='preload' href={`${assetPrefix}/_next/static/${buildId}/pages${pagePathname}`} as='script' nonce={this.props.nonce} />} <link rel='preload' href={`${assetPrefix}/_next/static/${buildId}/pages/_app.js`} as='script' nonce={this.props.nonce} /> <link rel='preload' href={`${assetPrefix}/_next/static/${buildId}/pages/_error.js`} as='script' nonce={this.props.nonce} /> {this.getPreloadDynamicChunks()} {this.getPreloadMainLinks()} {this.getCssLinks()} {styles || null} {children} </head> } } export class Main extends Component { static contextTypes = { _documentProps: PropTypes.any } render () { const { html } = this.context._documentProps return ( <div id='__next' dangerouslySetInnerHTML={{ __html: html }} /> ) } } export class NextScript extends Component { static contextTypes = { _documentProps: PropTypes.any } static propTypes = { nonce: PropTypes.string } getDynamicChunks () { const { dynamicImports, assetPrefix } = this.context._documentProps return dynamicImports.map((bundle) => { return <script async key={bundle.file} src={`${assetPrefix}/_next/${bundle.file}`} nonce={this.props.nonce} /> }) } getScripts () { const { assetPrefix, files } = this.context._documentProps if(!files || files.length === 0) { return null } return files.map((file) => { // Only render .js files here if(!/\.js$/.exec(file)) { return null } return <script key={file} src={`${assetPrefix}/_next/${file}`} nonce={this.props.nonce} async /> }) } static getInlineScriptSource (documentProps) { const { __NEXT_DATA__ } = documentProps const { page, pathname } = __NEXT_DATA__ return `__NEXT_DATA__ = ${htmlescape(__NEXT_DATA__)};__NEXT_LOADED_PAGES__=[];__NEXT_REGISTER_PAGE=function(r,f){__NEXT_LOADED_PAGES__.push([r, f])}${page === '/_error' ? `;__NEXT_REGISTER_PAGE(${htmlescape(pathname)},function(){var e = new Error('Page does not exist: ${htmlescape(pathname)}');e.statusCode=404;return {error:e}})`:''}` } render () { const { staticMarkup, assetPrefix, devFiles, __NEXT_DATA__ } = this.context._documentProps const { page, pathname, buildId } = __NEXT_DATA__ const pagePathname = getPagePathname(pathname) return <Fragment> {devFiles ? devFiles.map((file) => <script key={file} src={`${assetPrefix}/_next/${file}`} nonce={this.props.nonce} />) : null} {staticMarkup ? null : <script nonce={this.props.nonce} dangerouslySetInnerHTML={{ __html: NextScript.getInlineScriptSource(this.context._documentProps) }} />} {page !== '/_error' && <script async id={`__NEXT_PAGE__${pathname}`} src={`${assetPrefix}/_next/static/${buildId}/pages${pagePathname}`} nonce={this.props.nonce} />} <script async id={`__NEXT_PAGE__/_app`} src={`${assetPrefix}/_next/static/${buildId}/pages/_app.js`} nonce={this.props.nonce} /> <script async id={`__NEXT_PAGE__/_error`} src={`${assetPrefix}/_next/static/${buildId}/pages/_error.js`} nonce={this.props.nonce} /> {staticMarkup ? null : this.getDynamicChunks()} {staticMarkup ? null : this.getScripts()} </Fragment> } } function getPagePathname (pathname) { if (pathname === '/') { return '/index.js' } return `${pathname}.js` }