apollo-split.js

import ApolloClient from 'apollo-client';
import { getOperationAST } from 'graphql';
import { ApolloLink } from 'apollo-link';
import { HttpLink } from 'apollo-link-http';
import { WebSocketLink } from 'apollo-link-ws';
import { InMemoryCache } from 'apollo-cache-inmemory';

const httpLink = new HttpLink({
  uri: 'http://localhost:8080/graphql',
});

const wsLink = new WebSocketLink({
  uri: 'ws://localhost:8080/subscriptions',
  options: {
    reconnect: true,
  },
});

const link = ApolloLink.split(
  (operation) => {
    const operationAST = getOperationAST(operation.query, operation.operationName);
    return !!operationAST && operationAST.operation === 'subscription';
  },
  wsLink,
  httpLink,
);

new ApolloClient({
  link,
  cache: new InMemoryCache(),
});