schema.js

const axios = require('axios');

const {
	GraphQLObjectType,
	GraphQLString,
	GraphQLInt,
	GraphQLSchema,
	GraphQLList,
	GraphQLNonNull
} = require('graphql');
	
// // Hardcoded data
// const customers = [
// 	{id: '1', name: "Nikhil Arora", email: 'nikhil@gmail.com', age: 20},
// 	{id: '2', name: "Saumya Tiwari", email: 'saumya@gmail.com', age: 21},
// 	{id: '3', name: "Dalip Thakkar", email: 'dalip@gmail.com', age: 20}
// ];



// Customer Type
const CustomerType = new GraphQLObjectType({
	name: 'Customer',
	fields: () => ({
		id: {
			type: GraphQLString
		},
		name: {
			type: GraphQLString
		},
		email: {
			type: GraphQLString
		},
		age: {
			type: GraphQLInt
		}
	})
})


// Root Query
const RootQuery = new GraphQLObjectType({
	name: 'RootQueryType',
	fields: {
		customer: {
			type: CustomerType,
			args: {
				id: {
					type: GraphQLString
				}
			},
			resolve(parentValue, args) {
				// for (let i = 0; i < customers.length; i++) {
				// 	if (customers[i].id == args.id) {
				// 		return customers[i];
				// 	}
				// }
				
				return axios.get('http://localhost:3000/customers/' + args.id)
						.then(res => res.data);
			}
		},
		customers: {
			type: new GraphQLList(CustomerType),
			resolve(parentValue, args) {
				// return customers;

				return axios.get('http://localhost:3000/customers')
						.then(res => res.data);
			}
		}
	}
})


// Mutation
const mutation = new GraphQLObjectType({
	name: 'Mutation',
	fields: {
		addCustomer: {
			type: CustomerType,
			args: {
				name: {
					type: new GraphQLNonNull(GraphQLString)
				},
				email: {
					type: new GraphQLNonNull(GraphQLString)	
				},
				age: {
					type: new GraphQLNonNull(GraphQLInt)
				}
			},
			resolve(parentValue, args) {
				return axios.post('http://localhost:3000/customers', {
					name: args.name,
					email: args.email,
					age: args.age
				})
				.then(res => res.data);
			}
		},
		deleteCustomer: {
			type: CustomerType,
			args: {
				id: {
					type: new GraphQLNonNull(GraphQLString)
				}
			},
			resolve(parentValue, args) {
				return axios.delete('http://localhost:3000/customers/' + args.id)
				.then(res => res.data);
			}
		},
		updateCustomer: {
			type: CustomerType,
			args: {
				id: {
					type: GraphQLString
				},
				name: {
					type: GraphQLString
				},
				email: {
					type: GraphQLString	
				},
				age: {
					type: GraphQLInt
				}
			},
			resolve(parentValue, args) {
				return axios.patch('http://localhost:3000/customers/' + args.id, {
					name: args.name,
					email: args.email,
					age: args.age
				})
				.then(res => res.data);
			}
		},
	}
})


module.exports = new GraphQLSchema({
	query: RootQuery,
	mutation: mutation
});