Implement a basic graphql server api using node js.

Q: Implement a basic graphql server api using node js.

import { ApolloServer } from "@apollo/server"; import { startStandaloneServer } from "@apollo/server/standalone"; // Fake database const users = [ { id: "1", name: "Alice", email: "alice@example.com" }, { id: "2", name: "Bob", email: "bob@example.com" }, ]; // 1. Schema const typeDefs = `#graphql type User { id: ID! name: String! email: String! } type Query { user(id: ID!): User } `; // 2. Resolvers const resolvers = { Query: { user: async (_, args) => { const userId = args.id; // Simulate DB fetch const userData = users.find((user) => user.id === userId); return userData || null; }, }, }; // 3. Create server const server = new ApolloServer({ typeDefs, resolvers, }); // 4. Start server const { url } = await startStandaloneServer(server, { listen: { port: 4000 }, }); console.log(`Server ready at ${url}`);

Difficulty: 5/10

schema definition, resolver implementation, server setup

We can use ApolloServer to implement a graphql server

javascript

Scenario Questions

0-2 years experience

1How would you set up a simple GraphQL endpoint in Node.js that returns a list of books with title and author?
2If a client queries a field that you haven't defined in your schema, what response does GraphQL give?
3What steps would you take to add a new resolver for an 'addBook' mutation?

Follow-up Questions

Can you walk me through the code you’d write for a resolver that fetches data from a database?
What metrics would you monitor in production to ensure the GraphQL API stays healthy?
How would you handle errors so that clients receive useful GraphQL error responses?