List types in GraphQL - Mini Project: Build & Apply

GraphQL List Types Practice

📖 Scenario: You are building a simple GraphQL schema for a bookstore. You want to store a list of book titles available in the store.

🎯 Goal: Create a GraphQL schema that defines a Bookstore type with a field books that is a list of strings representing book titles.

📋 What You'll Learn

Define a GraphQL type called Bookstore

Add a field called books to Bookstore

The books field must be a list of strings

Use proper GraphQL list syntax for the books field

💡 Why This Matters

🌍 Real World

GraphQL schemas often need to represent collections of items, like lists of books, users, or products.

💼 Career

Understanding list types and nullability in GraphQL is essential for backend developers working with APIs.

1

Define the Bookstore type

Create a GraphQL type called Bookstore with no fields yet.

GraphQL

# Your code here
type Bookstore {
  # Add fields here
}

Need a hint?

Start by writing type Bookstore { } to define the type.

2

Add the books field

Inside the Bookstore type, add a field called books with type [String] to represent a list of book titles.

GraphQL

type Bookstore {
  # Add the books field as a list of strings
}

Need a hint?

Use square brackets [] around String to make it a list type.

3

Make the books list non-nullable

Modify the books field so that the list itself cannot be null by adding an exclamation mark ! after the list type.

GraphQL

type Bookstore {
  # Make the books list non-nullable
}

Need a hint?

Add ! after the list type to make the list non-nullable.

4

Make the book titles non-nullable

Modify the books field so that each book title inside the list is also non-nullable by adding an exclamation mark ! after String inside the list.

GraphQL

type Bookstore {
  # Make each book title non-nullable
}

Need a hint?

Add ! after String inside the brackets to make each item non-nullable.