create-graphql-node

const typeDefs = `
    type Mutation {
        createUser(name: String!, email: String!): User
    }
`;

const resolvers = {
    Mutation: {
        createUser: (parent, args) => {
            const newUser = Object.assign({id: users.length + 1}, args);
            users.push(newUser);
            return newUser;
        }
    }
};