Implementing Pagination, Filtering, and Sorting in REST APIs
🔍 Filtering — Filtering in REST APIs allows clients to retrieve only the data they need by specifying criteria. Common methods include using query parameters, path parameters, and request bodies. For example, using query parameters like GET /products?price_gt=50 filters products with a price greater than $50.
🔄 Sorting — Sorting enables clients to request data in a specific order, either ascending or descending, based on one or more fields. For instance, GET /products?sort=price&order=asc sorts products by price in ascending order.
📄 Pagination — Pagination is crucial for handling large datasets by breaking down responses into smaller, manageable portions. Techniques include offset-based pagination ( GET /items?limit=20&offset=100) and cursor-based pagination, which is more efficient for large datasets.
Filtering Techniques
🔗 Query Parameters — The most common method for filtering, allowing multiple conditions to be specified in a URL. For example, GET /products?category=Electronics&price=gt:50 filters products by category and price.
🛣️ Path Parameters — Useful for predefined filtering conditions, such as filtering by category in a URL path like GET /products/category/Electronics.
📦 Request Body — Allows complex filtering conditions to be sent as JSON or XML payloads, useful for multi-condition filters that can’t be easily represented in URLs.
🔄 Comparison Operators — Include operators like equal to (=), not equal to (!=), greater than (>), and less than (<) to refine filtering conditions.
🔗 Conjunction Operators — Use & (and) and | (or) to combine multiple filtering conditions, enabling complex queries.
Sorting Methods
⬆️ Ascending Sorting — Arranges data from lowest to highest value based on a specified field, such as GET /products?sort=price&order=asc for sorting by price.
⬇️ Descending Sorting — Arranges data from highest to lowest value, useful for fields like ratings or dates.
🔢 Multiple Column Sorting — Allows sorting by more than one field, providing a more nuanced order of results.
🔄 Sorting Algorithms — The choice of algorithm can affect performance, especially with large datasets. Common algorithms include quicksort and mergesort.
🔗 Query Parameters for Sorting — Typically involves parameters like sort and order to specify the field and direction of sorting.
Pagination Strategies
🔢 Offset Pagination — Uses limit and offset parameters to specify the number of items per page and the starting point, e.g., GET /items?limit=20&offset=100.
🔄 Cursor-based Pagination — More efficient for large datasets, using a cursor to mark the last item of the previous page.
📄 Page Number Pagination — Requests a specific page number, with the API calculating the offset, e.g., GET /items?page=2.
🔗 Keyset Pagination — Uses a key to determine the starting point for the next page, often more performant than offset pagination.
🔄 Seek Pagination — Similar to keyset, but uses a combination of keys and conditions to fetch the next set of results.
Originally published at https://dev.to on December 11, 2024.
