app.js

const express = require('express');
const bodyParser = require('body-parser');
const graphqlHttp = require('express-graphql').graphqlHTTP;
const { buildSchema } = require('graphql');
const mongoose = require('mongoose');

const Event = require('./models/event');

const app = express();

app.use(bodyParser.json());

app.use(
  '/graphql',
  graphqlHttp({
    schema: buildSchema(`
        type Event {
          _id: ID!
          title: String!
          description: String!
          price: Float!
          date: String!
        }
        input EventInput {
          title: String!
          description: String!
          price: Float!
          date: String!
        }
        type RootQuery {
            events: [Event!]!
        }
        type RootMutation {
            createEvent(eventInput: EventInput): Event
        }
        schema {
            query: RootQuery
            mutation: RootMutation
        }
    `),
    rootValue: {
      events: () => {
        return Event.find()
          .then(events => {
            return events.map(event => {
              return { ...event._doc, _id: event.id };
              // OR { ...event._doc, _id: event._doc._id.toString() }
              // event.id is an easy way offered to us by mongoose
            });
          })
          .catch(err => {
            throw err;
          });
      },
      createEvent: args => {
        const event = new Event({
          title: args.eventInput.title,
          description: args.eventInput.description,
          price: +args.eventInput.price,
          date: new Date(args.eventInput.date)
        });
        return event
          .save()
          .then(result => {
            console.log(result);
            return { ...result._doc, _id: result._doc._id.toString() };
          })
          .catch(err => {
            console.log(err);
            throw err;
          });
      }
    },
    graphiql: true
  })
);

mongoose
  .connect(
    `mongodb+srv://${process.env.MONGO_USER}:${
        process.env.MONGO_PASSWORD
      }@cluster0.4wcip.mongodb.net/${process.env.MONGO_DB}?retryWrites=true&w=majority`,
      {useNewUrlParser: true,
      useCreateIndex: true,
      useUnifiedTopology: true}
  )
  .then(() => {
    app.listen(3000, console.log("Your server is up dude!"));
  })
  .catch(err => {
    console.log(err);
  });