Testing¶
Quart’s usage of global variables (request etc) makes testing any
code that uses these variables more difficult. To combat this it is
best practice to only use these variables in the code directly called
by Quart e.g. route functions or before request functions. Thereafter
Quart provides a testing framework to control these globals.
Primarily testing should be done using a test client bound to the
Quart app being tested. As this is so common there is a helper method
test_client() which returns a bound client,
e.g.
@pytest.mark.asyncio
async def test_app(app):
client = app.test_client()
response = await client.get('/')
assert response.status_code == 200
Event loops¶
To test with quart you will need to have an event loop in order to call the async functions. This is possible to do manually, for example
def aiotest(func):
loop = asyncio.get_event_loop()
loop.run_until_complete(func())
@aiotest
async def test_app(app)
...
However it is much easier to use pytest-asyncio and the
@pytest.mark.asyncio decorator to do this for you. Note that
pytest is the recommended test runner and the examples throughout
assume pytest is used with pytest-asyncio.
Calling routes¶
The test client has helper methods for all the HTTP verbs
e.g. post(). These are helper methods
for open(), as such all the methods at
a minimum expect a path and optionally can have query parameters, json
or form data. A standard Response class is
returned. An example:
@pytest.mark.asyncio
async def test_create(app):
test_client = app.test_client()
data = {'name': 'foo'}
response = await test_client.post('/resource/', json=data)
assert response.status_code == 201
result = await response.get_json()
assert result == data
Context testing¶
It is often necessary to test something within the app or request contexts. This is simple enough for the app context,
@pytest.mark.asyncio
async def test_app_context(app):
async with app.app_context():
current_app.[use]
for the request context however the request context has to be faked, at a minimum this means the method and path must be supplied, e.g.
@pytest.mark.asyncio
async def test_app_context(app):
async with app.test_request_context("/", method="GET"):
request.[use]
Note
Any before_request or after_request functions are not
called when using the test_request_context. You can add
await app.preprocess_request() to ensure the
before_request functions are called.
@pytest.mark.asyncio
async def test_app_context(app):
async with app.test_request_context("/", method="GET"):
await app.preprocess_request()
# The before_request functions have now been called
request.[use]