Backend API

RESTful API design uses resource-based URLs with appropriate HTTP methods: GET to retrieve data, POST to create resources, PUT or PATCH to update, and DELETE to remove. Each method maps to a specific action on your resource, ensuring consistent and predictable endpoint behavior.

API versioning manages evolution by allowing clients to specify which version they need. Common strategies include URL path versioning (e.g., `/v1/products`), header-based versioning, or query parameters. Versioning prevents breaking changes for existing integrators while you develop new features.

Query parameters enable filtering, sorting, and pagination without changing your URL structure. Use parameters like `?category=electronics&sort=price&page=2&limit=10` to let clients request exactly the data they need, reducing bandwidth and improving response times.

Rate limiting headers communicate usage quotas and remaining requests to clients, preventing abuse and managing server load. Headers like `X-RateLimit-Limit`, `X-RateLimit-Remaining`, and `X-RateLimit-Reset` inform clients when they're approaching thresholds and when limits refresh.

HTTP status codes signal operation outcomes: 200 OK for successful retrieval, 201 Created for successful resource creation, 400 Bad Request for invalid input, 404 Not Found for missing resources, and 500 Internal Server Error for server failures. Consistent codes enable predictable client error handling.

Nested resource URLs reflect hierarchical relationships: `/users/{id}/orders` retrieves orders for a specific user, `/users/{id}/orders/{orderId}` accesses a particular order. This structure clarifies resource relationships and maintains consistency across your API design.