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// npm install graphql-ws ws @graphql-tools/schema

import { createServer } from 'http';
import { WebSocketServer } from 'ws';
import { useServer } from 'graphql-ws/lib/use/ws';
import { PubSub } from 'graphql-subscriptions';
import { makeExecutableSchema } from '@graphql-tools/schema';

const pubsub = new PubSub();
const MESSAGE_SENT = 'MESSAGE_SENT';

const typeDefs = `#graphql
  type Message { id: ID!  text: String!  sender: String!  sentAt: String! }
  type Query    { messages: [Message!]! }
  type Mutation { sendMessage(text: String!, sender: String!): Message! }
  type Subscription { messageSent: Message! }
`;