Nextjs urql订阅交换导入问题

Question

由于导入问题，我无法让urql订阅使用NextJS。

基本上，我使用的是这个在urql中推荐的graphql-ws库，它需要ws实现库(例如：'ws')。当我import WebSocket from 'ws'时，我得到了一个错误：Module not found: Can't resolve 'net'

import { createClient, defaultExchanges, subscriptionExchange, Client } from 'urql';
import { createClient as createWSClient } from 'graphql-ws';
import WebSocket from 'ws'; // <-- This causes the error

export const createUrqlClient = (): Client => {
  const wsClient = createWSClient({
    url: 'ws://xxx/graphql',
    webSocketImpl: WebSocket,
  });

  const client = createClient({
    url: 'http://xxx/graphql',
    exchanges: [
      ...defaultExchanges,
      subscriptionExchange({
        forwardSubscription: operation => ({
          subscribe: sink => ({
            unsubscribe: wsClient.subscribe(operation, sink),
          }),
        }),
      }),
    ],
  });

  return client;
};

我尝试了nextjs动态导入，但这两种方法都不起作用：

const WebSocket = dynamic(() => import('ws'), { ssr: false });
const WebSocket = dynamic(() => import('ws').then(module => module.default), { ssr: false });

我还试图修改next.config.js中的webpack配置，完全不捆绑这些库：

webpack: (config, { isServer }) => {
  if (!isServer) {
    config.resolve.fallback = {
      child_process: false,
      process: false,
      fs: false,
      util: false,
      http: false,
      https: false,
      tls: false,
      net: false,
      crypto: false,
      path: false,
      os: false,
      stream: false,
      zlib: false,
      querystring: false,
      events: false,
      'utf-8-validate': false,
      bufferutil: false,
    };
  }
  return config;
},

但是我得到了这些错误：

./node_modules/ws/lib/validation.js
Module not found: Can't resolve 'utf-8-validate' in '/home/danko/app/node_modules/ws/lib'
warn  - ./node_modules/ws/lib/buffer-util.js
Module not found: Can't resolve 'bufferutil' in '/home/danko/app/node_modules/ws/lib'

如果我也将'utf-8-validate': false和bufferutil: false添加到cfg中，就会得到以下错误：

TypeError: Class extends value undefined is not a constructor or null

所以从根本上说，就像你看到的那样，没有什么能正常工作.

这有多难，我不能是使用nextjs的urql订阅的唯一人，希望有人能帮助我。谢谢!

Answer 1

基本上就像我想的那样，不需要impl，因为可以使用原生html5 websocket，问题是它的服务器端的垃圾。

当typeof window !== 'undefined' (这是工作代码)时，我几乎不使用该交换：

import { createClient, dedupExchange, cacheExchange, subscriptionExchange, Client, Exchange } from 'urql';
import { multipartFetchExchange } from '@urql/exchange-multipart-fetch';
import { createClient as createWSClient } from 'graphql-ws';

export const createUrqlClient = (): Client => {
  const graphqlEndpoint = process.env!.NEXT_PUBLIC_GRAPHQL_ENDPOINT as string;
  const graphqlWebsocketEndpoint = process.env!.NEXT_PUBLIC_GRAPHQL_WS_ENDPOINT as string;

  let exchanges: Exchange[] | undefined = [dedupExchange, cacheExchange, multipartFetchExchange];

  if (typeof window !== 'undefined') {
    const wsClient = createWSClient({
      url: graphqlWebsocketEndpoint,
    });

    const subExchange = subscriptionExchange({
      forwardSubscription: operation => ({
        subscribe: sink => ({
          unsubscribe: wsClient.subscribe(operation, sink),
        }),
      }),
    });

    exchanges.push(subExchange);
  }

  const client = createClient({
    url: graphqlEndpoint,
    requestPolicy: 'cache-and-network',
    exchanges,
    fetchOptions: () => ({
      credentials: 'include',
    }),
  });

  return client;
};