Apollo GraphQL client

Based upon our previous implementation(s) of a server it’s now time to write some client code.

  • yarn add apollo-client
  • yarn add apollo-cache-inmemory
  • yarn add apollo-link-http
  • yarn add graphql-tag
  • yarn add isomorphic-fetch
  • yarn add -D @types/isomorphic-fetch

Now let’s create a simple script entry (this extends the previous post’s scripts section)

"scripts": {
  "build": "tsc",
  "client": "node client.js"
}

Now let’s create the file client.ts which should look like this

import ApolloClient from 'apollo-client';
import { InMemoryCache } from 'apollo-cache-inmemory';
import { HttpLink } from 'apollo-link-http';
import gql from 'graphql-tag';
import fetch from 'isomorphic-fetch';

const cache = new InMemoryCache();
const link = new HttpLink({
  uri: 'http://localhost:4000/',
  fetch: fetch
})

const client = new ApolloClient({
  cache,
  link,
});

client.query({
  query: gql`
    {
    users {
      firstName
      lastName
    }
  }`
  })
  .then((response: any) => console.log(response.data.users));

The response.data.users should now output the array of User objects.

Here’s an example of a mutation

client.mutate({
  mutation: gql`
    mutation {
      create(user: {
        firstName: "Miner",
        lastName: "FortyNiner"
      }) {
        firstName
        lastName
      }
    }
  `
}).then((response: any) => console.log(response.data.create));

Note: I had lots of issues around the fetch code, with errors such as Invariant Violation:
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.
. The addition of the isomorphic-fetch solved this problem.