import React from 'react' import PropTypes from 'prop-types' import { ApolloProvider, getDataFromTree } from 'react-apollo' import Head from 'next/head' import initApollo from './initApollo' // Gets the display name of a JSX component for dev tools function getComponentDisplayName (Component) { return Component.displayName || Component.name || 'Unknown' } export default ComposedComponent => { return class WithData extends React.Component { static displayName = `WithData(${getComponentDisplayName(ComposedComponent)})` static propTypes = { serverState: PropTypes.object.isRequired } static async getInitialProps (ctx) { // Initial serverState with apollo (empty) let serverState = { apollo: { data: { } } } // Evaluate the composed component's getInitialProps() let composedInitialProps = {} if (ComposedComponent.getInitialProps) { composedInitialProps = await ComposedComponent.getInitialProps(ctx) } // Run all GraphQL queries in the component tree // and extract the resulting data if (!process.browser) { const apollo = initApollo() // Provide the `url` prop data in case a GraphQL query uses it const url = {query: ctx.query, pathname: ctx.pathname} try { // Run all GraphQL queries await getDataFromTree( ) } catch (error) { // Prevent Apollo Client GraphQL errors from crashing SSR. // Handle them in components via the data.error prop: // http://dev.apollodata.com/react/api-queries.html#graphql-query-data-error } // getDataFromTree does not call componentWillUnmount // head side effect therefore need to be cleared manually Head.rewind() // Extract query data from the Apollo store serverState = { apollo: { data: apollo.cache.extract() } } } return { serverState, ...composedInitialProps } } constructor (props) { super(props) this.apollo = initApollo(this.props.serverState.apollo.data) } render () { return ( ) } } }