HTTP replay engine

Record and replay the HTTP interactions by setting the HTTP engine to HTTPEngineReplay. This is useful for fast and deterministic tests.

Inspired by VCR for Ruby and the similar projects for Python.


This feature is experimental, and the format in which records are saved on disk is subject to change in future versions.

Engine parameters


An iterable of Paths to specify the record stores. If a request matches a record from several paths, the last one will be used.

recording (optional)

A bool telling wether real HTTP requests will be send (and saved) instead of loaded from an existing record. Otherwise, no HTTP requests will be sent at all, and exceptions will be raised if no matching requests are found in the record store.

replay_request_modifier (optional)

Allow to modify the request before looking it up in the record store.

replay_response_modifier (optional)

Allow to modify the response after retrieving it from the record store.

recording_request_modifier (optional)

Allow to modify the request before sending the HTTP interaction for real. Only used in recording mode. Note that the argument has not been modified by replay_request_modifier.

recording_response_modifier (optional)

Allow to modify the response received from a real HTTP interaction before saving it to the record store. Only used in recording mode. Note that after being saved, the returned value will then pass through replay_response_modifier before being sent to the caller.

recording_compute_basename (optional)

Allow to compute the base name of the record file to be saved. A .json extension will be appended to the returned value. Only used in recording mode.


>>> from sdkite import Client
>>> from sdkite.http import HTTPAdapterSpec
>>> from sdkite.http.engine_replay import HTTPEngineReplay

>>> class TableTennis(Client):
...     _http = HTTPAdapterSpec("")
...     def ping(self):
...         return self._http.get("ping").data_str

>>> TableTennis._http.set_engine(HTTPEngineReplay, [Path("replay")])

>>> table_tennis = TableTennis()