GraphQL Modules Example

app.ts

import { GraphQLModule } from '@graphql-modules/core';
import { UserModule } from './user-module';
import { ChatModule } from './chat-module';

export const appModule = new GraphQLModule({
  imports: [
    UserModule,
    ChatModule,
  ],
});

chat-module.ts

import { GraphQLModule } from '@graphql-modules/core';
import gql from 'graphql-tag';

export const ChatModule = new GraphQLModule({
  typeDefs: gql`
    # Query declared again, adding only the part of the schema that relevant
    type Query {
      myChats: [Chat]
    }

    # User declared again- extends any other `User` type that loaded into the appModule
    type User {
      chats: [Chat]
    }

    type Chat {
      id: ID!
      users: [User]
      messages: [ChatMessage]
    }

    type ChatMessage {
      id: ID!
      content: String!
      user: User!
    }
  `,
  resolvers: {
    Query: {
       myChats: (root, args, { getChats, currentUser }) => getChats(currentUser),  
    },
    User: {
      // This module implements only the part of `User` it adds
      chats: (user, args, { getChats }) => getChats(user), 
    },
  },
});

main.ts

import { appModule } from './modules/app';
import { ApolloServer } from 'apollo-server';

const { schema, context } = appModule;

const server = new ApolloServer({ 
  schema,
  context,
  introspection: true,
});

server.listen();

user-module.ts

import { GraphQLModule } from '@graphql-modules/core';
import gql from 'graphql-tag';

export const UserModule = new GraphQLModule({
  typeDefs: gql`
    type Query {
      me: User
    }

    # This is a basic User, with just the basics of a user object
    type User {
      id: ID!
      username: String!
      email: String!
    }
  `,
  resolvers: {
    Query: {
       me: (root, args, { currentUser ) => currentUser,  
    },
    User: {
      id: user => user._id,
      username: user => user.username,
      email: user => user.email.address, 
    }, 
  },
});