Minimal GraphQL Example

index.js

const { ApolloServer } = require('apollo-server');
const { GraphQLSchema, GraphQLObjectType, GraphQLString } = require('graphql');

const Query = new GraphQLObjectType({
  name: 'Query',
  description: 'The query operation entry type.',
  fields: {
    hello: {
      type: GraphQLString,
      description: 'Our first query field, how exciting!',
      resolve: () => "world!",
    },
  },
});

const schema = new GraphQLSchema({ query: Query });

const server = new ApolloServer({ schema });

server.listen();