A pytest plugin that records network interactions in your tests via VCR.py.
- Straightforward
pytest.mark.vcr, that reflectsVCR.use_cassettesAPI; - Combining multiple VCR cassettes;
- Network access blocking;
- The
rewriterecording mode that rewrites cassettes from scratch.
This project can be installed via pip:
pip install pytest-recordingimport pytest
import requests
# cassettes/{module_name}/test_single.yaml will be used
@pytest.mark.vcr
def test_single():
assert requests.get("http://httpbin.org/get").text == '{"get": true}'
# cassettes/{module_name}/example.yaml will be used
@pytest.mark.default_cassette("example.yaml")
@pytest.mark.vcr
def test_default():
assert requests.get("http://httpbin.org/get").text == '{"get": true}'
# these cassettes will be used in addition to the default one
@pytest.mark.vcr("/path/to/ip.yaml", "/path/to/get.yaml")
def test_multiple():
assert requests.get("http://httpbin.org/get").text == '{"get": true}'
assert requests.get("http://httpbin.org/ip").text == '{"ip": true}'
# Make assertions based on the cassette calls/responses:
@pytest.mark.vcr
def test_call_count(vcr):
assert requests.get("http://httpbin.org/get").text == '{"get": true}'
assert requests.get("http://httpbin.org/ip").text == '{"ip": true}'
# See https://vcrpy.readthedocs.io/en/latest/advanced.html for more info
# about the Cassette object:
assert vcr.play_count == 2Run your tests:
pytest --record-mode=once test_network.pypytest-recording uses the none VCR recording mode by default to prevent unintentional network requests.
To allow them you need to pass a different recording mode (e.g. once) via the --record-mode CLI option to your test command.
See more information about available recording modes in the official VCR documentation
You can provide the recording configuration with the vcr_config fixture, which could be any scope - session,
package, module, or function. It should return a dictionary that will be passed directly to VCR.use_cassettes
under the hood.
import pytest
@pytest.fixture(scope="module")
def vcr_config():
return {"filter_headers": ["authorization"]}For more granular control you need to pass these keyword arguments to individual pytest.mark.vcr marks, and in this case
all arguments will be merged into a single dictionary with the following priority (low -> high):
vcr_configfixture- all marks from the most broad scope ("session") to the most narrow one ("function")
Example:
import pytest
pytestmark = [pytest.mark.vcr(ignore_localhost=True)]
@pytest.fixture(scope="module")
def vcr_config():
return {"filter_headers": ["authorization"]}
@pytest.mark.vcr(filter_headers=[])
def test_one():
...
@pytest.mark.vcr(filter_query_parameters=["api_key"])
def test_two():
...Resulting VCR configs for each test:
test_one-{"ignore_localhost": True, "filter_headers": []}test_two-{"ignore_localhost": True, "filter_headers": ["authorization"], "filter_query_parameters": ["api_key"]}
You can get access to the used VCR instance via pytest_recording_configure hook. It might be useful for registering
custom matchers, persisters, etc.:
# conftest.py
def jurassic_matcher(r1, r2):
assert r1.uri == r2.uri and "JURASSIC PARK" in r1.body, \
"required string (JURASSIC PARK) not found in request body"
def pytest_recording_configure(config, vcr):
vcr.register_matcher("jurassic", jurassic_matcher)You can disable the VCR.py integration entirely by passing the --disable-recording CLI option.
It is possible to rewrite a cassette from scratch and not extend it with new entries as it works now with the all record mode from VCR.py.
However, it will rewrite only the default cassette and won't touch extra cassettes.
import pytest
@pytest.fixture(scope="module")
def vcr_config():
return {"record_mode": "rewrite"}Or via command-line option:
$ pytest --record-mode=rewrite tests/To have more confidence that your tests will not go over the wire, you can block it with pytest.mark.block_network mark:
import pytest
import requests
@pytest.mark.block_network
def test_multiple():
assert requests.get("http://httpbin.org/get").text == '{"get": true}'
...
# in case of access
RuntimeError: Network is disabledBesides marks, the network access could be blocked globally with --block-network command-line option.
However, if VCR.py recording is enabled, the network is not blocked for tests with pytest.mark.vcr.
Example:
import pytest
import requests
@pytest.mark.vcr
def test_multiple():
assert requests.get("http://httpbin.org/get").text == '{"get": true}'Run pytest:
$ pytest --record-mode=once --block-network tests/The network blocking feature supports socket-based transports and pycurl.
It is possible to allow access to specified hosts during network blocking:
import pytest
import requests
@pytest.mark.block_network(allowed_hosts=["httpbin.*"])
def test_access():
assert requests.get("http://httpbin.org/get").text == '{"get": true}'
with pytest.raises(RuntimeError, match=r"^Network is disabled$"):
requests.get("http://example.com")Or via command-line option:
$ pytest --record-mode=once --block-network --allowed-hosts=httpbin.*,localhost tests/Or via vcr_config fixture:
import pytest
@pytest.fixture(autouse=True)
def vcr_config():
return {"allowed_hosts": ["httpbin.*"]}Looking for more examples? Check out this article about pytest-recording.
To run the tests:
$ tox -p allFor more information, take a look at our contributing guide
Pytest-recording supports:
- CPython 3.7, 3.8, 3.9, 3.10, 3.11, and 3.12
- PyPy 7 (3.6)
The code in this project is licensed under MIT license. By contributing to pytest-recording, you agree that your contributions will be licensed under its MIT license.