Setting up and dependencies installation

mkdir graphql-server-express
cd graphql-server-express

npm init -y

npm install express apollo-server-express
npm install --save-dev @babel/core @babel/node @babel/preset-env babel-cli babel-preset-es2015 nodemon

Pretty straight-forward so far, right? Good.

Let's jump into the code

Create a .babelrc file in the root folder

{
  "presets": ["@babel/preset-env"]
}

This file will enable us to use some ES6 capabilities such as the use of import.

Create src folder and the index.js file in it as follows

import express from "express";
import { ApolloServer, gql } from "apollo-server-express";

const typeDefs = gql`
  type Query {
    hello: String
  }
`;

const resolvers = {
  Query: {
    hello: () => "Hello world!",
  },
};

const server = new ApolloServer({ typeDefs, resolvers });

const app = express();
server.applyMiddleware({ app });

app.listen({ port: 4001 }, () =>
  console.log(`Server listening on http://localhost:4001${server.graphqlPath}`)
);

A couple of things about this file:

• This is the entry point of the server
• I use one file for all the code just for simplicity - you can decide to split it into multiple files
• I use the port 4001 but you can use another port if you want

How to start the server with nodemon

Now update the script command in the package.json file as follows

...
  "scripts": {
    "start": "nodemon --exec babel-node src/index.js"
  }
...

Now run npm start in the terminal. The GraphQL Playground will be available at http://localhost:4001/graphql (or any other address/port you used).