import Document, { Head, Main, NextScript } from 'next/document'
import Helmet from 'react-helmet'
export default class extends Document {
static async getInitialProps (...args) {
const documentProps = await super.getInitialProps(...args)
// see https://github.com/nfl/react-helmet#server-usage for more information
// 'head' was occupied by 'renderPage().head', we cannot use it
return { ...documentProps, helmet: Helmet.renderStatic() }
}
// should render on
get helmetHtmlAttrComponents () {
return this.props.helmet.htmlAttributes.toComponent()
}
// should render on
get helmetBodyAttrComponents () {
return this.props.helmet.bodyAttributes.toComponent()
}
// should render on
get helmetHeadComponents () {
return Object.keys(this.props.helmet)
.filter(el => el !== 'htmlAttributes' && el !== 'bodyAttributes')
.map(el => this.props.helmet[el].toComponent())
}
get helmetJsx () {
return ()
}
render () {
return (
{ this.helmetJsx }
{ this.helmetHeadComponents }
)
}
}