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[英]Server-side render a modal in React upon clicking a button for NextJS
[英]Server-side render data when using Apollo Client with NextJS?
我的組件目前在瀏覽器上補水,這是我想避免的。 當您訪問該鏈接時,我希望它與它需要顯示的所有數據一起預先水合,即在服務器上呈現。 目前,該組件如下所示:
import { graphql } from "react-apollo";
import gql from 'graphql-tag';
import withData from "../../apollo/with-data";
import getPostsQuery from '../../apollo/schemas/getPostsQuery.graphql';
const renderers = {
paragraph: (props) => <Typography variant="body2" gutterBottom {...props} />,
};
const GET_POSTS = gql`${getPostsQuery}`;
const PostList = ({data: {error, loading, posts}}) => {
let payload;
if(error) {
payload = (<div>There was an error!</div>);
} else if(loading) {
payload = (<div>Loading...</div>);
} else {
payload = (
<>
{posts.map((post) => (
<div>
<div>{post.title}</div>
<div>{post.body}</div>
</div>
))}
</>
);
}
return payload;
};
export default withData(graphql(GET_POSTS)(PostList));
如您所見,它首先在后台獲取帖子時顯示文本Loading...
我不想要那個。 我希望它已經與獲取的數據預先水合。
作為參考,我的 Apollo 初始化如下所示:
// apollo/with-data.js
import React from "react";
import PropTypes from "prop-types";
import { ApolloProvider, getDataFromTree } from "react-apollo";
import initApollo from "./init-apollo";
export default ComposedComponent => {
return class WithData extends React.Component {
static displayName = `WithData(${ComposedComponent.displayName})`;
static propTypes = {
serverState: PropTypes.object.isRequired
};
static async getInitialProps(ctx) {
const headers = ctx.req ? ctx.req.headers : {};
let serverState = {};
// 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(headers);
// Provide the `url` prop data in case a graphql query uses it
const url = { query: ctx.query, pathname: ctx.pathname };
// Run all graphql queries
const app = (
<ApolloProvider client={apollo}>
<ComposedComponent url={url} {...composedInitialProps} />
</ApolloProvider>
);
await getDataFromTree(app);
// Extract query data from the Apollo's store
const state = apollo.getInitialState();
serverState = {
apollo: {
// Make sure to only include Apollo's data state
data: state.data
}
};
}
return {
serverState,
headers,
...composedInitialProps
};
}
constructor(props) {
super(props);
this.apollo = initApollo(this.props.headers, this.props.serverState);
}
render() {
return (
<ApolloProvider client={this.apollo}>
<ComposedComponent {...this.props} />
</ApolloProvider>
);
}
};
};
// apollo/init-apollo.js
import { InMemoryCache } from 'apollo-cache-inmemory';
import { ApolloClient } from 'apollo-client';
import { ApolloLink } from 'apollo-link';
import { onError } from 'apollo-link-error';
import { HttpLink } from 'apollo-link-http';
import fetch from 'isomorphic-fetch';
let apolloClient = null;
// Polyfill fetch() on the server (used by apollo-client)
if (!process.browser) {
global.fetch = fetch;
}
const create = (headers, initialState) => new ApolloClient({
initialState,
link: ApolloLink.from([
onError(({ graphQLErrors, networkError }) => {
if (graphQLErrors) {
graphQLErrors.forEach(({ message, locations, path }) => console.log(
`[GraphQL error]: Message: ${message}, Location: ${locations}, Path: ${path}`,
));
}
if (networkError) console.log(`[Network error]: ${networkError}`);
}),
new HttpLink({
// uri: 'https://dev.schandillia.com/graphql',
uri: process.env.CMS,
credentials: 'same-origin',
}),
]),
ssrMode: !process.browser, // Disables forceFetch on the server (so queries are only run once)
cache: new InMemoryCache(),
});
export default function initApollo(headers, initialState = {}) {
// Make sure to create a new client for every server-side request so that data
// isn't shared between connections (which would be bad)
if (!process.browser) {
return create(headers, initialState);
}
// Reuse client on the client-side
if (!apolloClient) {
apolloClient = create(headers, initialState);
}
return apolloClient;
}
更新:我嘗試將https://github.com/zeit/next.js/tree/canary/examples/with-apollo的官方 withApollo 示例合並到我的項目中,但它在getDataFromTree()
上引發了一個不變的錯誤:
元素類型無效:應為字符串(用於內置組件)或類/函數(用於復合組件)但得到:未定義。
對於/init/apollo.js
、 /components/blog/PostList.jsx
和/pages/Blog/jsx
文件,我使用了與示例 repo 中完全相同的代碼。 在我的具體情況下,唯一的區別是我有一個明確的_app.jsx
,內容如下:
/* eslint-disable max-len */
import '../static/styles/fonts.scss';
import '../static/styles/style.scss';
import '../static/styles/some.css';
import CssBaseline from '@material-ui/core/CssBaseline';
import { ThemeProvider } from '@material-ui/styles';
import jwt from 'jsonwebtoken';
import withRedux from 'next-redux-wrapper';
import App, {
Container,
} from 'next/app';
import Head from 'next/head';
import React from 'react';
import { Provider } from 'react-redux';
import makeStore from '../reducers';
import mainTheme from '../themes/main-theme';
import getSessIDFromCookies from '../utils/get-sessid-from-cookies';
import getLanguageFromCookies from '../utils/get-language-from-cookies';
import getUserTokenFromCookies from '../utils/get-user-token-from-cookies';
import removeFbHash from '../utils/remove-fb-hash';
class MyApp extends App {
static async getInitialProps({ Component, ctx }) {
let userToken;
let sessID;
let language;
if (ctx.isServer) {
ctx.store.dispatch({ type: 'UPDATEIP', payload: ctx.req.headers['x-real-ip'] });
userToken = getUserTokenFromCookies(ctx.req);
sessID = getSessIDFromCookies(ctx.req);
language = getLanguageFromCookies(ctx.req);
const dictionary = require(`../dictionaries/${language}`);
ctx.store.dispatch({ type: 'SETLANGUAGE', payload: dictionary });
if(ctx.res) {
if(ctx.res.locals) {
if(!ctx.res.locals.authenticated) {
userToken = null;
sessID = null;
}
}
}
if (userToken && sessID) { // TBD: validate integrity of sessID
const userInfo = jwt.verify(userToken, process.env.JWT_SECRET);
ctx.store.dispatch({ type: 'ADDUSERINFO', payload: userInfo });
}
ctx.store.dispatch({ type: 'ADDSESSION', payload: sessID }); // component will be able to read from store's state when rendered
}
const pageProps = Component.getInitialProps ? await Component.getInitialProps(ctx) : {};
return { pageProps };
}
componentDidMount() {
// Remove the server-side injected CSS.
const jssStyles = document.querySelector('#jss-server-side');
if (jssStyles) {
jssStyles.parentNode.removeChild(jssStyles);
}
// Register serviceWorker
if ('serviceWorker' in navigator) { navigator.serviceWorker.register('/serviceWorker.js'); }
// Handle FB's ugly redirect URL hash
removeFbHash(window, document);
}
render() {
const { Component, pageProps, store } = this.props;
return (
<Container>
<Head>
<meta name="viewport" content="user-scalable=0, initial-scale=1, minimum-scale=1, width=device-width, height=device-height, shrink-to-fit=no" />
<meta httpEquiv="X-UA-Compatible" content="IE=edge,chrome=1" />
<link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png" />
<link rel="icon" type="image/png" sizes="32x32" href="/favicon-32x32.png" />
<link rel="icon" type="image/png" sizes="194x194" href="/favicon-194x194.png" />
<link rel="icon" type="image/png" sizes="192x192" href="/android-chrome-192x192.png" />
<link rel="icon" type="image/png" sizes="16x16" href="/favicon-16x16.png" />
<link rel="manifest" href="/site.webmanifest" />
<link rel="mask-icon" href="/safari-pinned-tab.svg" color="#663300" />
<meta name="msapplication-TileColor" content="#da532c" />
<meta name="msapplication-TileImage" content="/mstile-144x144.png" />
</Head>
<ThemeProvider theme={mainTheme}>
{/* CssBaseline kickstart an elegant, consistent, and simple baseline to build upon. */}
<CssBaseline />
<Provider store={store}>
<Component {...pageProps} />
</Provider>
</ThemeProvider>
</Container>
);
}
}
export default withRedux(makeStore)(MyApp);
擺脫這個文件不是一個選項,因為這是我處理一些預加載 cookie 邏輯的地方。
供參考的 repo 位於https://github.com/amitschandillia/proost/tree/master/web
使用 Next.js 和 Apollo 時,您需要實現 2 個關鍵目標:SSR 和緩存網絡數據。 兩者兼顧是一個艱難的平衡。 但這是可能的。
這樣做的方法是:
現在,如果您有一些頁面數據需要編輯、添加或刪除,並且您希望在更改后更新頁面而不刷新頁面,那么以上是不夠的。 因為例如,如果您編輯數據,典型/推薦的 Apollo 方法是不做任何事情。 阿波羅為您神奇地處理這一切。 除了初始數據必須來自 apollo 緩存並且它必須有一個 Id 字段。 現在,由於您直接從服務器加載了初始數據,很可能您沒有從先前緩存的數據中讀取數據。
因此,需要下面的第 2 步來啟用數據更改時數據的自動刷新。
這樣,您就可以毫不費力地繼續使用所有您喜歡的最新工具,例如 useQuery 和 getDataFromTree。
一些幫助研究:
我相信你應該使用getMarkupFromTree
如本期建議的https://github.com/apollographql/react-apollo/issues/3251以及如何實現https://github.com/trojanowski/react-a鈎子/問題/52 。
看來,如果你想使用鈎子,你需要 @trojanowski 的react-apollo-hooks
package。
有人說這個解決方案不起作用。 一些人認為它有一些低效率,例如,它將整個標記呈現兩次,一次由下一個,一次是為了獲取阿波羅查詢。 作為回應,他們建議做一些事情,比如直接在 get initial props 中調用查詢,這只是比應該做的更多的工作,因為 ssr 功能應該是開箱即用的。
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