Designing RESTful endpoints for a complex inventory system at scale means following REST conventions consistently while explicitly planning for statelessness, versioning, caching, and controlled data payloads from the outset.
Key Points: • Use stateless request handling and correct HTTP methods, GET for reads, POST for creation, PUT/PATCH for updates, and DELETE for removal, so behavior is predictable. • Design meaningful, resource-oriented URI structures, such as /products/{id}/inventory, instead of action-oriented endpoints. • Version the API, for example via a /v1/ path prefix, so future breaking changes don't disrupt existing consumers. • Apply HTTP caching headers and server-side caching for frequently read, infrequently changed inventory data. • Support partial responses or pagination so clients aren't forced to pull the entire dataset for large inventories.
Example: Instead of an endpoint like /getProductStock, the API exposes GET /v1/products/{id}/stock, returns paginated results for /v1/products, and sets Cache-Control headers so clients and CDNs can cache stable catalog data.
Interview Tip: A concise interview answer is:
"I'd stick to resource-oriented, versioned URIs and correct HTTP methods, keep the API stateless, add pagination so large inventory listings don't overwhelm clients, and layer in caching for read-heavy, rarely-changing data. Versioning from day one also means I can evolve the API later without breaking existing consumers."