Nock

Nock intercepts requests based on hostname, path, method, query strings, headers, and body using strings, regex, or functions, as detailed in the 'Specifying hostname' and 'Specifying path' sections.

It can reply with static data, JSON, files, streams, or dynamic callbacks, including custom status codes and headers, enabling realistic mock setups without network calls.

Methods like .isDone() and .pendingMocks() help ensure all mocked requests are made, preventing false positives in tests, as explained in the 'Expectations' section.

The Nock Back feature records real HTTP interactions to generate fixtures for playback, simplifying test maintenance and setup, covered in the 'Recording' and 'Nock Back' sections.