GraphQL live example

index.js

const express = require('express');
const graphqlHTTP = require('express-graphql');
const { makeExecutableSchema } = require('graphql-tools');

const events = [{
  id: 1,
  name: 'APIs and IPAs',
  description: 'Cool event',
  startTime: 'evening',
  endTime: 'late evening'
},{
  id: 2,
  name: 'Seattle JS Hackers',
  description: 'Chill event',
  startTime: 'evening',
  endTime: 'somewhat later'
}];

const typeDefs = `
  type Event {
    id: ID
    name: String!
    description: String
    startTime: String
    endTime: String
  }

  type Query {
    listEvents(name: String!): [Event]
  }

  input EventInput {
    id: ID
    name: String!
    description: String
    startTime: String
    endTime: String
  }

  type Mutation {
    saveEvent(event: EventInput): Event
  }
`;

const resolvers = {
  Query: {
    listEvents: (root, { name }, context, ast) => {
      if (name) {
        const re = new RegExp(name, 'i');
        return events.filter(e => e.name.match(re))
      }
      return events;
    }
  },
  Mutation: {
    saveEvent: (root, { event }, context, ast) => {
      if (event.id) {
        const existingEvent = events.find(e => e.id == event.id);
        if (!existingEvent) {
          throw new Error('Event not found');
        }
        for (const key in event) {
          existingEvent[key] = event[key]; 
        }
        return existingEvent;
      } else {
        event.id = events.length + 1;
        events.push(event);
        return event;
      }
    }
  }
}

const schema = makeExecutableSchema({
  typeDefs,
  resolvers
})

express()
  .use('/graphql', graphqlHTTP({ 
    graphiql: true,
    schema
  }))
  .listen(8080, ()=>console.log('runnin\''));