Apollo server + express , GraphQL sample

index.js

// Apollo server + express , GraphQL sample
const express = require('express');
const { ApolloServer, gql } = require('apollo-server-express');

const typeDefs = gql`
  type Todo {
    id: Int!
    title: String
  }
  type Query {
    hello: String
    todo(id: Int): Todo
    todos: [Todo]    
  }
`;
// Provide resolver functions for your schema fields
const todos = [
  {
      id: 1,
      title: 'task-test-1',
  },
  {
      id: 2,
      title: 'task-test-2',
  },
  {
      id: 3,
      title: 'task-test-3',
  },
  {
      id: 4,
      title: 'task-test-4',
  }
]
const resolvers = {
  Query: {
    hello: () => 'Hello world!',
    todo(parent, args, context, info){
      return todos.find(todo => todo.id === args.id);
    },
    todos: () => {
        return todos
    },    
  },
};

const server = new ApolloServer({ typeDefs, resolvers });
const app = express();
server.applyMiddleware({ app });

app.listen({ port: 4000 }, () => {
    console.log(`🚀 Server ready at http://localhost:4000${server.graphqlPath}`);
});