Filtering & Searching
A professional API shouldn't just return 10,000 items. It must allow clients to drill down into exactly what they need using Query Parameters.
1. Basic Filtering
Use simple key-value pairs in the query string for exact matches.
GET /products?category=electronics&status=active
2. Advanced Filter Patterns
For more than just equality, use brackets to define operators in the URI.
# Price greater than or equal to 500
GET /products?price[gte]=500
# Created after a certain date
GET /users?createdAt[gt]=2023-01-01
3. Full-Text Searching
Provide a dedicated q or search parameter for keyword-based searching across multiple fields.
GET /articles?search=javascript+best+practices
4. Field Selection (Sparse Fieldsets)
Allow clients to request only the fields they need to save bandwidth and improve performance.
GET /users/123?fields=name,email,avatar
Backend Tip: Don't just pipe the query string directly into your database. Always Parse and Sanitize the filters to prevent NoSQL injection or performance-killing "heavy" queries.
