JUHE API Marketplace

Pagination, Filtering & Sorting

3 min read
By Olivia Bennett

Introduction: Why API efficiency matters

In a data-driven world, slow or bloated APIs hurt user experience. Whether you’re powering dashboards, search tools, or mobile feeds, sending too much data—or the wrong data—wastes bandwidth and server resources.

The good news: implementing pagination, filtering, and sorting makes REST APIs faster, easier to consume, and more scalable.

The Three Pillars of Data Handling

Pagination

Break large datasets into manageable chunks.

Filtering

Return only the records relevant to the client’s query.

Sorting

Ensure results are in a meaningful order for your use case.

Pagination: Breaking Down Large Datasets

When your dataset grows, loading everything at once isn’t viable.

Common strategies

  • Offset/limit: Use query params like ?offset=0&limit=20.
  • Cursor-based: Use a cursor token that marks a place in the data, e.g., ?cursor=eyJpZCI6MTIzfQ==&limit=20.

Pros and cons

Offset/limit

  • Easy to implement
  • Slower for huge datasets due to large scans and unstable pages when rows are inserted or deleted

Cursor-based

  • More consistent performance and stable pagination
  • More complex state handling and requires deterministic sort keys

Implementation tips

  • Set a max limit to avoid abuse (e.g., cap at 100 or 1000 depending on use case).
  • Return metadata like total_count (if affordable) and/or next_cursor.
  • Use stable, indexed sort keys (e.g., (created_at, id)).

Filtering: Getting Only What You Need

Filtering helps your API return only relevant data.

Query parameters approach

Example: GET /articles?author_id=42&status=published

Complex filters

  • Combine filters with AND/OR.
  • Use ranges: ?price_min=10&price_max=50.
  • Support in-array matches: ?tags=api,design.
  • Consider reserved operators for inequality and ranges, e.g., ?created_at[gte]=2024-01-01&created_at[lte]=2024-12-31.

Security considerations

  • Whitelist allowed filter fields and operators.
  • Validate types (e.g., integers, enums, ISO dates) and reject unknown fields.
  • Avoid exposing internal column names or unbounded regex.
  • Rate-limit and consider caching popular filtered queries.

Sorting: Controlling The Order of Results

Sorting ensures clients receive results in a meaningful order.

Common sort patterns

  • GET /products?sort=price_asc
  • GET /products?sort=-created_at (leading minus for descending)

Multi-field sort

  • Allow chaining: ?sort=category_asc,price_desc
  • Ensure all sort fields are indexed or covered by composite indexes where practical.

Performance tradeoffs

  • Sorting on non-indexed or computed fields can be expensive.
  • Consider secondary sorts (e.g., append ,id_asc) to ensure deterministic ordering.

Bringing It All Together

A real-world-style example on https://hub.juheapi.com/:

GET /v1/items?category=api&sort=-popularity&limit=10&offset=20

This request:

  • Filters by category (api)
  • Sorts by popularity (descending)
  • Paginates with limit 10, offset 20

The response can include JSON like: { "items": [...], "pagination": { "total_count": 124, "limit": 10, "offset": 20, "next_offset": 30 } } For cursor-based pagination, a similar response might include: { "items": [...], "page": { "next_cursor": "eyJpZCI6MTIzfQ==", "limit": 10 } }

Best Practices Checklist

  • Limit maximum limit value and validate inputs
  • Return pagination metadata (next_cursor or next_offset)
  • Document all filterable and sortable fields with types and operators
  • Use stable, indexed sort keys; add tie-breakers
  • Combine pagination, filtering, and sorting for flexibility
  • Consider ETags and If-None-Match for caching
  • Provide examples in your API docs and enforce consistent error formats

Conclusion: Efficient APIs = Happy Users

Efficient APIs translate to faster responses, lower costs, and happier customers. By implementing pagination, filtering, and sorting as first-class features, you give consumers control and keep your backend healthy. It’s a small investment in design that pays off with every request.