graphql-implementation

# GraphQL Implementation Build GraphQL APIs with proper schema design, resolvers, and performance optimization. ## Schema Definition ```graphql type User { id: ID! name: String! email: String! posts(limit: Int = 10): [Post!]! } type Post { id: ID! title: String! content: String! author: User! createdAt: DateTime! } type Query { user(id: ID!): User users(limit: Int, offset: Int): [User!]! post(id: ID!): Post } type Mutation { createUser(input: CreateUserInput!): User! createPost(input: CreatePostInput!): Post! } input CreateUserInput { name: String! email: String! } ``` ## Apollo Server Setup ```javascript const { ApolloServer } = require('@apollo/server'); const { startStandaloneServer } = require('@apollo/server/standalone'); const resolvers = { Query: { user: (_, { id }, { dataSources }) => dataSources.userAPI.getUser(id), users: (_, { limit, offset }, { dataSources }) => dataSources.userAPI.getUsers({ limit, offset }) }, User: { posts: (user, { limit }, { dataSources }) => dataSources.postAPI.getPostsByUser(user.id, limit) }, Mutation: { createUser: (_, { input }, { dataSources }) => dataSources.userAPI.createUser(input) } }; const server = new ApolloServer({ typeDefs, resolvers }); ``` ## DataLoader for N+1 Prevention ```javascript const DataLoader = require('dataloader'); const userLoader = new DataLoader(async (ids) => { const users = await User.find({ _id: { $in: ids } }...