Apollo-client: How to properly shutdown/close apollo-client?

[matyashlavacek]

Intended outcome:

I am able to close apollo-client gracefully.
Here is a sample of a code I'm using:

// Running under nodejs (not a browser)
require('isomorphic-fetch');
global.WebSocket = require('ws');

import gql from 'graphql-tag';
import ApolloClient from 'apollo-client';
import { InMemoryCache, NormalizedCacheObject } from 'apollo-cache-inmemory';
import { split } from 'apollo-link';
import { HttpLink } from 'apollo-link-http';
import { WebSocketLink } from 'apollo-link-ws';
import { getMainDefinition } from 'apollo-utilities';

const httpLink = new HttpLink({
  uri: 'http://localhost:4000/',
});

const wsLink = new WebSocketLink({
  uri: 'ws://localhost:4000/graphql',
  options: {
    reconnect: true,
  },
});

const link = split(
  ({ query }) => {
    const definition = getMainDefinition(query);
    return (
      definition.kind === 'OperationDefinition' &&
      definition.operation === 'subscription'
    );
  },
  wsLink,
  httpLink,
);

let client!: ApolloClient<NormalizedCacheObject>;

const booksQuery = gql`
  query books {
    books {
      title
      author
    }
  }
`;

beforeAll(() => {
  client = new ApolloClient({
    link,
    cache: new InMemoryCache(),
  });
});

afterAll(async () => {
  await client.clearStore();
  client.stop();
});

test('books', async () => {
  const resp = await client.query({
    query: booksQuery,
  });
  console.log(resp.data.books);
});

Actual outcome:

When using apollo-client with jest as per example above I get the following warning:

Jest did not exit one second after the test run has completed.

This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with `--detectOpenHandles` to troubleshoot this issue.

How to reproduce the issue:

Run the code above.

Versions

$ npx envinfo@latest --preset apollo --clipboard
npx: installed 1 in 0.873s

  System:
    OS: macOS 10.15.3
  Binaries:
    Node: 12.16.2 - /opt/local/bin/node
    npm: 6.14.4 - /opt/local/bin/npm
  Browsers:
    Chrome: 81.0.4044.122
    Firefox: 74.0.1
    Safari: 13.0.5
  npmPackages:
    apollo-boost: ^0.4.7 => 0.4.7 
    apollo-link-ws: ^1.0.20 => 1.0.20 
  npmGlobalPackages:
    apollo: 2.27.3

Does anybody know how to properly close apollo client so I don't get this warning?

[matyashlavacek]

For those who hit the same issue

(wsLink as any).subscriptionClient.close();

[guiquintelas]

For those using NestJs make sure to close the app last, only then the msg will disappear

afterAll(async () => {
  await apolloClient.clearStore();
  apolloClient.stop();
  (wsLink as any).subscriptionClient.close();
  await app.close(); // <---
});