在node.js中使用ApolloClient。"在全局范围内没有找到fetch，也没有通过fetcher"[英] Using ApolloClient with node.js. "fetch is not found globally and no fetcher passed"

问题描述

I am attempting to use an Apollo Client on a node.js server to interface with another GraphQL API using the following code:

import fetch from 'node-fetch'
import { createHttpLink } from 'apollo-link-http'

import ApolloClient from 'apollo-boost'
import { API_URL } from '...'

const client = new ApolloClient({
  link: createHttpLink({
    uri: API_URL,
    fetch: fetch,
  }),
})

Which yields the following error:

module initialization error: Error
fetch is not found globally and no fetcher passed, to fix pass a fetch for
your environment like https://www.npmjs.com/package/node-fetch.

For example:
import fetch from 'node-fetch';
import { createHttpLink } from 'apollo-link-http';

const link = createHttpLink({ uri: '/graphql', fetch: fetch });
at Object.checkFetcher (/var/task/node_modules/apollo-link-http-common/lib/bundle.umd.js:78:19)
at createHttpLink (/var/task/node_modules/apollo-link-http/lib/bundle.umd.js:32:30)
at new HttpLink (/var/task/node_modules/apollo-link-http/lib/bundle.umd.js:203:38)
at new DefaultClient (/var/task/node_modules/apollo-boost/lib/index.js:80:24)

I understand that the Apollo Client by default is expecting to be run in a browser context where a fetch method will be available, and that in a node.js I need to polyfill or otherwise provide a fetch method, but I having trouble figuring out exactly how to do this.

Following the example code at https://www.apollographql.com/docs/link/#apollo-client it appears that I should be able to pass this information in using the link option, and reading the apollo-boost source code seems to suggest that you can pass this information in using fetcherOptions, but neither of these solutions seem to work.

Can anyone provide some example code for initializing an Apollo Client in node.js with a fetcher?

For reference here is my package.json

{
  "name": "API-Service",
  "version": "1.0.0",
  "description": "",
  "private": true,
  "scripts": {},
  "dependencies": {
    "apollo-boost": "^0.1.6",
    "apollo-link-http": "^1.5.4",
    "graphql": "^0.13.2",
    "babel-polyfill": "^6.26.0",
    "json-rules-engine": "^2.1.0",
    "node-fetch": "^2.1.2",
    "mysql": "^2.15.0"
  }
}

推荐答案

It turns out that the ApolloClient provided by the apollo-boost library does not accept a link option. Switching to use the vanilla apollo-client allows you to specify your fetching mechanism.

Although apollo-boost and apollo-client both export an ApolloClient in the docs, they take wildly different options.

import fetch from 'node-fetch'
import { createHttpLink } from 'apollo-link-http'
import { InMemoryCache } from 'apollo-cache-inmemory'

import ApolloClient from 'apollo-client'
import { API_URL } from '...'

const client = new ApolloClient({
  link: createHttpLink({
    uri: API_URL,
    fetch: fetch,
  }),
  cache: new InMemoryCache(),
})

其他推荐答案

If you still want to use Apollo Boost in Node.js but need to polyfill the native fetch API of the browser, try out cross-fetch. I used it for my minimal example over here. And that's how it can be used after installing it:

import 'cross-fetch/polyfill';
import ApolloClient from 'apollo-boost';

const client = new ApolloClient({
  uri: 'https://api.domain.com/graphql',
});

其他推荐答案

You can add fetch option directly to the ApolloClient from apollo-boost. Here is the example code

Ref. https://www.apollographql.com/docs/react/essentials/get-started/#configuration-options

import ApolloClient from 'apollo-boost';
import fetch from 'node-fetch';

const client = new ApolloClient({
    fetch: fetch
});

Tested with apollo-boost version 0.4.3