Filtering, Sorting, and Search

An API receives:

GET /orders?statsu=confirmed

The caller misspelled status.

If the server ignores the unknown parameter, it returns an unfiltered list with 200 OK. The client may then use the wrong data without noticing the typo. Rejecting the unsupported parameter makes the mistake visible.

This lesson designs how callers narrow, order, and search a collection. Every query you publish is a promise about performance as well as syntax.

1. A Filter Narrows One Collection

A filter is a query parameter that removes items without changing which collection is addressed. In