Object types in GraphQL - Mini Project: Build & Apply

Building a GraphQL Object Type for a Bookstore

📖 Scenario: You are creating a simple GraphQL API for a bookstore. You want to define the structure of the data for books so that clients can query book details easily.

🎯 Goal: Build a GraphQL Book object type with specific fields to represent books in the bookstore.

📋 What You'll Learn

Create a GraphQL object type named Book

Add fields id, title, author, and publishedYear with correct types

Use ID! type for id to uniquely identify each book

Use String! type for title and author

Use Int type for publishedYear which can be null if unknown

💡 Why This Matters

🌍 Real World

GraphQL object types define the shape of data clients can request from APIs, making data fetching clear and efficient.

💼 Career

Understanding GraphQL schemas is essential for backend developers and API designers working with modern web applications.

1

Define the Book object type

Create a GraphQL object type called Book with no fields yet.

GraphQL

type Book {
  # Your code here
}

Need a hint?

Start by writing type Book { } to define the object type.

2

Add the id field

Inside the Book type, add a field called id with type ID!.

GraphQL

type Book {
  # Add the id field here
}

Need a hint?

The id field should be non-nullable and use the ID! type.

3

Add title and author fields

Add two more fields inside Book: title and author, both with type String!.

GraphQL

type Book {
  id: ID!
  # Add title and author fields here
}

Need a hint?

Both title and author are required strings, so use String!.

4

Add optional publishedYear field

Add a field called publishedYear with type Int (nullable) inside the Book type.

GraphQL

type Book {
  id: ID!
  title: String!
  author: String!
  # Add publishedYear field here
}

Need a hint?

The publishedYear can be missing, so do not add an exclamation mark.