Bidirectional relationships in GraphQL - Mini Project: Build & Apply

Bidirectional Relationships in GraphQL

📖 Scenario: You are building a simple social network database where users can follow each other. Each user should know who they follow and who follows them.

🎯 Goal: Create a GraphQL schema that models users with bidirectional relationships: each user has a list of users they follow and a list of users who follow them.

📋 What You'll Learn

Define a User type with id and name fields

Add a follows field to User that lists users this user follows

Add a followers field to User that lists users who follow this user

Create a root Query type to fetch all users

💡 Why This Matters

🌍 Real World

Social networks and apps often need to model relationships where users follow each other, requiring bidirectional links.

💼 Career

Understanding bidirectional relationships in GraphQL is important for backend developers building APIs for social platforms and connected data.

1

Define the User type with basic fields

Define a GraphQL User type with fields id of type ID! and name of type String!.

GraphQL

# Define the User type with id and name fields

Need a hint?

Start by defining a type User with id and name fields.

2

Add the follows field to User

Add a field called follows to the User type. It should be a list of User objects, non-nullable, and the list itself should be non-nullable (use [User!]!).

GraphQL

type User {
  id: ID!
  name: String!
  # Add follows field here
}

Need a hint?

The follows field should be a list of users this user follows.

3

Add the followers field to User

Add a field called followers to the User type. It should be a list of User objects, non-nullable, and the list itself should be non-nullable (use [User!]!).

GraphQL

type User {
  id: ID!
  name: String!
  follows: [User!]!
  # Add followers field here
}

Need a hint?

The followers field should be a list of users who follow this user.

4

Create the Query type to fetch all users

Define a root Query type with a field called users that returns a non-nullable list of non-nullable User objects (use [User!]!).

GraphQL

type User {
  id: ID!
  name: String!
  follows: [User!]!
  followers: [User!]!
}

# Define Query type here

Need a hint?

The Query type should allow fetching all users with the users field.