Cursor-based pagination in GraphQL - Mini Project: Build & Apply

Cursor-based Pagination in GraphQL

📖 Scenario: You are building a GraphQL API for a blog platform. The blog has many posts, and you want to show posts to users in small chunks (pages) instead of all at once. This helps the app load faster and makes it easier for users to browse posts.

🎯 Goal: Create a GraphQL query that implements cursor-based pagination to fetch blog posts in pages. You will set up the data structure, add a pagination configuration, write the main query logic using cursors, and complete the pagination response structure.

📋 What You'll Learn

Create a list of posts with exact titles and IDs

Add a variable for the page size limit

Write a GraphQL query that fetches posts after a given cursor

Complete the pagination response with edges, nodes, and pageInfo

💡 Why This Matters

🌍 Real World

Cursor-based pagination is used in many apps to efficiently load data in chunks, improving user experience and reducing server load.

💼 Career

Understanding cursor-based pagination is important for backend developers working with APIs, especially GraphQL, to build scalable and performant data fetching.

1

Create the posts data list

Create a list called posts with these exact entries: { id: "1", title: "GraphQL Basics" }, { id: "2", title: "Advanced GraphQL" }, { id: "3", title: "GraphQL Pagination" }, { id: "4", title: "GraphQL Subscriptions" }, { id: "5", title: "GraphQL Security" }.

GraphQL

# Your code here

Hint

Use a list of objects with id and title keys exactly as shown.

2

Add the page size limit variable

Add a variable called pageSize and set it to 2 to limit the number of posts returned per page.

GraphQL

posts = [
  { id: "1", title: "GraphQL Basics" },
  { id: "2", title: "Advanced GraphQL" },
  { id: "3", title: "GraphQL Pagination" },
  { id: "4", title: "GraphQL Subscriptions" },
  { id: "5", title: "GraphQL Security" }
]
# Your code here

Hint

Set pageSize to 2 to fetch two posts per page.

3

Write the GraphQL query with cursor logic

Write a GraphQL query called getPosts that takes an optional after cursor argument of type ID. Use posts and pageSize to return posts after the cursor, limited by pageSize. Use edges with cursor and node fields.

GraphQL

posts = [
  { id: "1", title: "GraphQL Basics" },
  { id: "2", title: "Advanced GraphQL" },
  { id: "3", title: "GraphQL Pagination" },
  { id: "4", title: "GraphQL Subscriptions" },
  { id: "5", title: "GraphQL Security" }
]

pageSize = 2

# Your code here

Hint

Use edges with cursor and node fields inside the query.

4

Complete the pagination response with pageInfo

Add the pageInfo field inside the posts query response. Include hasNextPage and endCursor fields to complete the cursor-based pagination structure.

GraphQL

posts = [
  { id: "1", title: "GraphQL Basics" },
  { id: "2", title: "Advanced GraphQL" },
  { id: "3", title: "GraphQL Pagination" },
  { id: "4", title: "GraphQL Subscriptions" },
  { id: "5", title: "GraphQL Security" }
]

pageSize = 2

query getPosts($after: ID) {
  posts(after: $after, first: pageSize) {
    edges {
      cursor
      node {
        id
        title
      }
    }
    # Your code here
  }
}

Hint

Include pageInfo with hasNextPage and endCursor inside the posts field.