Enum types in GraphQL - Mini Project: Build & Apply

GraphQL Enum Types for User Roles

📖 Scenario: You are building a user management system where each user has a specific role. Roles can be ADMIN, EDITOR, or VIEWER. You want to use GraphQL enum types to define these roles clearly in your schema.

🎯 Goal: Create a GraphQL schema that defines an enum type called UserRole with the values ADMIN, EDITOR, and VIEWER. Then use this enum type in a User type to specify the user's role.

📋 What You'll Learn

Define an enum type called UserRole with values ADMIN, EDITOR, and VIEWER.

Create a User type with fields id (ID!), name (String!), and role (UserRole!).

Add a query type users that returns a list of User objects.

💡 Why This Matters

🌍 Real World

Enum types in GraphQL help define fixed sets of options, like user roles, status codes, or categories, making APIs clearer and safer.

💼 Career

Understanding enums is essential for backend developers working with GraphQL APIs to enforce valid data and improve API design.

1

Define the UserRole enum type

Create a GraphQL enum type called UserRole with the values ADMIN, EDITOR, and VIEWER.

GraphQL

# Your code here
enum UserRole {
  ADMIN
  EDITOR
  VIEWER
}

Need a hint?

Use the enum keyword followed by the enum name and list the values inside curly braces.

2

Create the User type using UserRole enum

Create a GraphQL type called User with fields id of type ID!, name of type String!, and role of type UserRole!.

GraphQL

enum UserRole {
  ADMIN
  EDITOR
  VIEWER
}

# Your code here
type User {
  id: ID!
  name: String!
  role: UserRole!
}

Need a hint?

Define the User type with the specified fields and use the UserRole enum for the role field.

3

Add a users query returning a list of User

Add a Query type with a field called users that returns a list of User objects. Use the syntax [User!]! to indicate a non-null list of non-null users.

GraphQL

enum UserRole {
  ADMIN
  EDITOR
  VIEWER
}

type User {
  id: ID!
  name: String!
  role: UserRole!
}

# Your code here
type Query {
  users: [User!]!
}

Need a hint?

Define the Query type with a users field that returns a list of User objects.

4

Complete the schema with schema definition

Add the schema definition specifying that the query root type is Query.

GraphQL

enum UserRole {
  ADMIN
  EDITOR
  VIEWER
}

type User {
  id: ID!
  name: String!
  role: UserRole!
}

type Query {
  users: [User!]!
}

# Your code here
schema {
  query: Query
}

Need a hint?

Use the schema keyword to define the root query type.