Pagination metadata in response in Rest API - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this pagination metadata JSON?

Given this API response snippet, what is the value of total_pages?

Rest API

{
  "data": ["item1", "item2"],
  "pagination": {
    "page": 2,
    "per_page": 2,
    "total_items": 5,
    "total_pages": 3
  }
}

A 4

B 2

C 5

D 3

💡 Hint

Total pages is total items divided by items per page, rounded up.

There are 5 total items and 2 items per page, so 5/2 = 2.5, rounded up to 3 total pages.

🧠 Conceptual

intermediate

Which field is essential to indicate the current page in pagination metadata?

In a paginated API response, which metadata field tells the client which page of results is being returned?

A "page"

B "total_items"

C "per_page"

D "total_pages"

💡 Hint

Think about which number tells you where you are in the list of pages.

The "page" field indicates the current page number being returned in the response.

❓ Predict Output

advanced

What is the value of has_next in this pagination metadata?

Given this pagination metadata, what is the value of has_next if it is defined as page < total_pages?

Rest API

{
  "page": 4,
  "per_page": 10,
  "total_items": 45,
  "total_pages": 5
}

A null

B false

C true

D error

💡 Hint

Compare current page number with total pages.

Since page 4 is less than total_pages 5, has_next is true.

🔧 Debug

advanced

What error does this pagination metadata cause?

This API returns pagination metadata with total_pages set to 0 but total_items is 10 and per_page is 5. What problem will this cause?

Rest API

{
  "page": 1,
  "per_page": 5,
  "total_items": 10,
  "total_pages": 0
}

A No error, metadata is valid

B Client thinks there are no pages and shows no results

C Division by zero error on client side

D Infinite loop in pagination navigation

💡 Hint

If total_pages is zero but there are items, what does that mean for pagination?

total_pages should be at least 1 if there are items. Zero misleads client to think no pages exist.

🚀 Application

expert

How to calculate offset for database query from pagination metadata?

Given pagination metadata with page and per_page, which formula correctly calculates the offset to fetch items from a database?

A offset = (page - 1) * per_page

B offset = page * per_page

C offset = per_page - page

D offset = total_items - per_page

💡 Hint

Offset is how many items to skip before starting to fetch the current page.

Offset is zero-based, so for page 1 offset is 0, for page 2 offset is per_page, etc.