Testing

Reference

Functional testing framework for Falcon apps and Falcon itself.

Falcon’s testing module contains various test classes and utility functions to support functional testing for both Falcon-based apps and the Falcon framework itself.

The testing framework supports both unittest and pytest:

# -----------------------------------------------------------------
# unittest
# -----------------------------------------------------------------

from falcon import testing
import myapp


class MyTestCase(testing.TestCase):
    def setUp(self):
        super(MyTestCase, self).setUp()

        # Assume the hypothetical `myapp` package has a
        # function called `create()` to initialize and
        # return a `falcon.API` instance.
        self.app = myapp.create()


class TestMyApp(MyTestCase):
    def test_get_message(self):
        doc = {u'message': u'Hello world!'}

        result = self.simulate_get('/messages/42')
        self.assertEqual(result.json, doc)


# -----------------------------------------------------------------
# pytest
# -----------------------------------------------------------------

from falcon import testing
import pytest

import myapp


# Depending on your testing strategy and how your application
# manages state, you may be able to broaden the fixture scope
# beyond the default 'function' scope used in this example.

@pytest.fixture()
def client():
    # Assume the hypothetical `myapp` package has a function called
    # `create()` to initialize and return a `falcon.API` instance.
    return testing.TestClient(myapp.create())


def test_get_message(client):
    doc = {u'message': u'Hello world!'}

    result = client.simulate_get('/messages/42')
    assert result.json == doc
class falcon.testing.Result(iterable, status, headers) [source]

Encapsulates the result of a simulated WSGI request.

Parameters:
  • iterable (iterable) – An iterable that yields zero or more bytestrings, per PEP-3333
  • status (str) – An HTTP status string, including status code and reason string
  • headers (list) – A list of (header_name, header_value) tuples, per PEP-3333
status

HTTP status string given in the response

Type: str
status_code

The code portion of the HTTP status string

Type: int
headers

A case-insensitive dictionary containing all the headers in the response, except for cookies, which may be accessed via the cookies attribute.

Note

Multiple instances of a header in the response are currently not supported; it is unspecified which value will “win” and be represented in headers.

Type: CaseInsensitiveDict
cookies

A dictionary of falcon.testing.Cookie values parsed from the response, by name.

Type: dict
encoding

Text encoding of the response body, or None if the encoding can not be determined.

Type: str
content

Raw response body, or bytes if the response body was empty.

Type: bytes
text

Decoded response body of type unicode under Python 2.7, and of type str otherwise. If the content type does not specify an encoding, UTF-8 is assumed.

Type: str
json

Deserialized JSON body. Will be None if the body has no content to deserialize. Otherwise, raises an error if the response is not valid JSON.

Type: JSON serializable
class falcon.testing.Cookie(morsel) [source]

Represents a cookie returned by a simulated request.

Parameters: morsel – A Morsel object from which to derive the cookie data.
name

The cookie’s name.

Type: str
value

The value of the cookie.

Type: str
expires

Expiration timestamp for the cookie, or None if not specified.

Type: datetime.datetime
path

The path prefix to which this cookie is restricted, or None if not specified.

Type: str
domain

The domain to which this cookie is restricted, or None if not specified.

Type: str
max_age

The lifetime of the cookie in seconds, or None if not specified.

Type: int
secure

Whether or not the cookie may only only be transmitted from the client via HTTPS.

Type: bool
http_only

Whether or not the cookie may only be included in unscripted requests from the client.

Type: bool
falcon.testing.simulate_request(app, method='GET', path='/', query_string=None, headers=None, body=None, json=None, file_wrapper=None, wsgierrors=None, params=None, params_csv=True, protocol='http', host='falconframework.org', remote_addr=None, extras=None) [source]

Simulates a request to a WSGI application.

Performs a request against a WSGI application. Uses wsgiref.validate to ensure the response is valid WSGI.

Keyword Arguments:
  • app (callable) – The WSGI application to call
  • method (str) – An HTTP method to use in the request (default: ‘GET’)
  • path (str) –

    The URL path to request (default: ‘/’).

    Note

    The path may contain a query string. However, neither query_string nor params may be specified in this case.

  • protocol – The protocol to use for the URL scheme (default: ‘http’)
  • params (dict) – A dictionary of query string parameters, where each key is a parameter name, and each value is either a str or something that can be converted into a str, or a list of such values. If a list, the value will be converted to a comma-delimited string of values (e.g., ‘thing=1,2,3’).
  • params_csv (bool) – Set to False to encode list values in query string params by specifying multiple instances of the parameter (e.g., ‘thing=1&thing=2&thing=3’). Otherwise, parameters will be encoded as comma-separated values (e.g., ‘thing=1,2,3’). Defaults to True.
  • query_string (str) – A raw query string to include in the request (default: None). If specified, overrides params.
  • headers (dict) – Additional headers to include in the request (default: None)
  • body (str) – A string to send as the body of the request. Accepts both byte strings and Unicode strings (default: None). If a Unicode string is provided, it will be encoded as UTF-8 in the request.
  • json (JSON serializable) – A JSON document to serialize as the body of the request (default: None). If specified, overrides body and the Content-Type header in headers.
  • file_wrapper (callable) – Callable that returns an iterable, to be used as the value for wsgi.file_wrapper in the environ (default: None). This can be used to test high-performance file transmission when resp.stream is set to a file-like object.
  • host (str) – A string to use for the hostname part of the fully qualified request URL (default: ‘falconframework.org’)
  • remote_addr (str) – A string to use as the remote IP address for the request (default: ‘127.0.0.1’)
  • wsgierrors (io) – The stream to use as wsgierrors (default sys.stderr)
  • extras (dict) – Additional CGI variables to add to the WSGI environ dictionary for the request (default: None)
Returns:

The result of the request

Return type:

Result

falcon.testing.simulate_get(app, path, **kwargs) [source]

Simulates a GET request to a WSGI application.

Equivalent to:

simulate_request(app, 'GET', path, **kwargs)
Parameters:
  • app (callable) – The WSGI application to call
  • path (str) –

    The URL path to request.

    Note

    The path may contain a query string. However, neither query_string nor params may be specified in this case.

Keyword Arguments:
  • params (dict) – A dictionary of query string parameters, where each key is a parameter name, and each value is either a str or something that can be converted into a str, or a list of such values. If a list, the value will be converted to a comma-delimited string of values (e.g., ‘thing=1,2,3’).
  • params_csv (bool) – Set to False to encode list values in query string params by specifying multiple instances of the parameter (e.g., ‘thing=1&thing=2&thing=3’). Otherwise, parameters will be encoded as comma-separated values (e.g., ‘thing=1,2,3’). Defaults to True.
  • query_string (str) – A raw query string to include in the request (default: None). If specified, overrides params.
  • headers (dict) – Additional headers to include in the request (default: None)
  • file_wrapper (callable) – Callable that returns an iterable, to be used as the value for wsgi.file_wrapper in the environ (default: None). This can be used to test high-performance file transmission when resp.stream is set to a file-like object.
  • protocol – The protocol to use for the URL scheme (default: ‘http’)
  • host (str) – A string to use for the hostname part of the fully qualified request URL (default: ‘falconframework.org’)
  • remote_addr (str) – A string to use as the remote IP address for the request (default: ‘127.0.0.1’)
  • extras (dict) – Additional CGI variables to add to the WSGI environ dictionary for the request (default: None)
falcon.testing.simulate_head(app, path, **kwargs) [source]

Simulates a HEAD request to a WSGI application.

Equivalent to:

simulate_request(app, 'HEAD', path, **kwargs)
Parameters:
  • app (callable) – The WSGI application to call
  • path (str) –

    The URL path to request.

    Note

    The path may contain a query string. However, neither query_string nor params may be specified in this case.

Keyword Arguments:
  • params (dict) – A dictionary of query string parameters, where each key is a parameter name, and each value is either a str or something that can be converted into a str, or a list of such values. If a list, the value will be converted to a comma-delimited string of values (e.g., ‘thing=1,2,3’).
  • params_csv (bool) – Set to False to encode list values in query string params by specifying multiple instances of the parameter (e.g., ‘thing=1&thing=2&thing=3’). Otherwise, parameters will be encoded as comma-separated values (e.g., ‘thing=1,2,3’). Defaults to True.
  • query_string (str) – A raw query string to include in the request (default: None). If specified, overrides params.
  • headers (dict) – Additional headers to include in the request (default: None)
  • protocol – The protocol to use for the URL scheme (default: ‘http’)
  • host (str) – A string to use for the hostname part of the fully qualified request URL (default: ‘falconframework.org’)
  • remote_addr (str) – A string to use as the remote IP address for the request (default: ‘127.0.0.1’)
  • extras (dict) – Additional CGI variables to add to the WSGI environ dictionary for the request (default: None)
falcon.testing.simulate_post(app, path, **kwargs) [source]

Simulates a POST request to a WSGI application.

Equivalent to:

simulate_request(app, 'POST', path, **kwargs)
Parameters:
  • app (callable) – The WSGI application to call
  • path (str) – The URL path to request
Keyword Arguments:
  • params (dict) – A dictionary of query string parameters, where each key is a parameter name, and each value is either a str or something that can be converted into a str, or a list of such values. If a list, the value will be converted to a comma-delimited string of values (e.g., ‘thing=1,2,3’).
  • params_csv (bool) – Set to False to encode list values in query string params by specifying multiple instances of the parameter (e.g., ‘thing=1&thing=2&thing=3’). Otherwise, parameters will be encoded as comma-separated values (e.g., ‘thing=1,2,3’). Defaults to True.
  • headers (dict) – Additional headers to include in the request (default: None)
  • body (str) – A string to send as the body of the request. Accepts both byte strings and Unicode strings (default: None). If a Unicode string is provided, it will be encoded as UTF-8 in the request.
  • json (JSON serializable) – A JSON document to serialize as the body of the request (default: None). If specified, overrides body and the Content-Type header in headers.
  • protocol – The protocol to use for the URL scheme (default: ‘http’)
  • host (str) – A string to use for the hostname part of the fully qualified request URL (default: ‘falconframework.org’)
  • remote_addr (str) – A string to use as the remote IP address for the request (default: ‘127.0.0.1’)
  • extras (dict) – Additional CGI variables to add to the WSGI environ dictionary for the request (default: None)
falcon.testing.simulate_put(app, path, **kwargs) [source]

Simulates a PUT request to a WSGI application.

Equivalent to:

simulate_request(app, 'PUT', path, **kwargs)
Parameters:
  • app (callable) – The WSGI application to call
  • path (str) – The URL path to request
Keyword Arguments:
  • params (dict) – A dictionary of query string parameters, where each key is a parameter name, and each value is either a str or something that can be converted into a str, or a list of such values. If a list, the value will be converted to a comma-delimited string of values (e.g., ‘thing=1,2,3’).
  • params_csv (bool) – Set to False to encode list values in query string params by specifying multiple instances of the parameter (e.g., ‘thing=1&thing=2&thing=3’). Otherwise, parameters will be encoded as comma-separated values (e.g., ‘thing=1,2,3’). Defaults to True.
  • headers (dict) – Additional headers to include in the request (default: None)
  • body (str) – A string to send as the body of the request. Accepts both byte strings and Unicode strings (default: None). If a Unicode string is provided, it will be encoded as UTF-8 in the request.
  • json (JSON serializable) – A JSON document to serialize as the body of the request (default: None). If specified, overrides body and the Content-Type header in headers.
  • protocol – The protocol to use for the URL scheme (default: ‘http’)
  • host (str) – A string to use for the hostname part of the fully qualified request URL (default: ‘falconframework.org’)
  • remote_addr (str) – A string to use as the remote IP address for the request (default: ‘127.0.0.1’)
  • extras (dict) – Additional CGI variables to add to the WSGI environ dictionary for the request (default: None)
falcon.testing.simulate_options(app, path, **kwargs) [source]

Simulates an OPTIONS request to a WSGI application.

Equivalent to:

simulate_request(app, 'OPTIONS', path, **kwargs)
Parameters:
  • app (callable) – The WSGI application to call
  • path (str) – The URL path to request
Keyword Arguments:
  • params (dict) – A dictionary of query string parameters, where each key is a parameter name, and each value is either a str or something that can be converted into a str, or a list of such values. If a list, the value will be converted to a comma-delimited string of values (e.g., ‘thing=1,2,3’).
  • params_csv (bool) – Set to False to encode list values in query string params by specifying multiple instances of the parameter (e.g., ‘thing=1&thing=2&thing=3’). Otherwise, parameters will be encoded as comma-separated values (e.g., ‘thing=1,2,3’). Defaults to True.
  • headers (dict) – Additional headers to include in the request (default: None)
  • protocol – The protocol to use for the URL scheme (default: ‘http’)
  • host (str) – A string to use for the hostname part of the fully qualified request URL (default: ‘falconframework.org’)
  • remote_addr (str) – A string to use as the remote IP address for the request (default: ‘127.0.0.1’)
  • extras (dict) – Additional CGI variables to add to the WSGI environ dictionary for the request (default: None)
falcon.testing.simulate_patch(app, path, **kwargs) [source]

Simulates a PATCH request to a WSGI application.

Equivalent to:

simulate_request(app, 'PATCH', path, **kwargs)
Parameters:
  • app (callable) – The WSGI application to call
  • path (str) – The URL path to request
Keyword Arguments:
  • params (dict) – A dictionary of query string parameters, where each key is a parameter name, and each value is either a str or something that can be converted into a str, or a list of such values. If a list, the value will be converted to a comma-delimited string of values (e.g., ‘thing=1,2,3’).
  • params_csv (bool) – Set to False to encode list values in query string params by specifying multiple instances of the parameter (e.g., ‘thing=1&thing=2&thing=3’). Otherwise, parameters will be encoded as comma-separated values (e.g., ‘thing=1,2,3’). Defaults to True.
  • headers (dict) – Additional headers to include in the request (default: None)
  • body (str) – A string to send as the body of the request. Accepts both byte strings and Unicode strings (default: None). If a Unicode string is provided, it will be encoded as UTF-8 in the request.
  • json (JSON serializable) – A JSON document to serialize as the body of the request (default: None). If specified, overrides body and the Content-Type header in headers.
  • protocol – The protocol to use for the URL scheme (default: ‘http’)
  • host (str) – A string to use for the hostname part of the fully qualified request URL (default: ‘falconframework.org’)
  • remote_addr (str) – A string to use as the remote IP address for the request (default: ‘127.0.0.1’)
  • extras (dict) – Additional CGI variables to add to the WSGI environ dictionary for the request (default: None)
falcon.testing.simulate_delete(app, path, **kwargs) [source]

Simulates a DELETE request to a WSGI application.

Equivalent to:

simulate_request(app, 'DELETE', path, **kwargs)
Parameters:
  • app (callable) – The WSGI application to call
  • path (str) – The URL path to request
Keyword Arguments:
  • params (dict) – A dictionary of query string parameters, where each key is a parameter name, and each value is either a str or something that can be converted into a str, or a list of such values. If a list, the value will be converted to a comma-delimited string of values (e.g., ‘thing=1,2,3’).
  • params_csv (bool) – Set to False to encode list values in query string params by specifying multiple instances of the parameter (e.g., ‘thing=1&thing=2&thing=3’). Otherwise, parameters will be encoded as comma-separated values (e.g., ‘thing=1,2,3’). Defaults to True.
  • headers (dict) – Additional headers to include in the request (default: None)
  • protocol – The protocol to use for the URL scheme (default: ‘http’)
  • host (str) – A string to use for the hostname part of the fully qualified request URL (default: ‘falconframework.org’)
  • remote_addr (str) – A string to use as the remote IP address for the request (default: ‘127.0.0.1’)
  • extras (dict) – Additional CGI variables to add to the WSGI environ dictionary for the request (default: None)
class falcon.testing.TestClient(app, headers=None) [source]

Simulates requests to a WSGI application.

This class provides a contextual wrapper for Falcon’s simulate_* test functions. It lets you replace this:

simulate_get(app, '/messages')
simulate_head(app, '/messages')

with this:

client = TestClient(app)
client.simulate_get('/messages')
client.simulate_head('/messages')

Note

The methods all call self.simulate_request() for convenient overriding of request preparation by child classes.

Parameters: app (callable) – A WSGI application to target when simulating requests
Keyword Arguments:
headers (dict) – Default headers to set on every request (default None). These defaults may be overridden by passing values for the same headers to one of the simulate_*() methods.
simulate_delete(path='/', **kwargs) [source]

Simulates a DELETE request to a WSGI application.

(See also: falcon.testing.simulate_delete())

simulate_get(path='/', **kwargs) [source]

Simulates a GET request to a WSGI application.

(See also: falcon.testing.simulate_get())

simulate_head(path='/', **kwargs) [source]

Simulates a HEAD request to a WSGI application.

(See also: falcon.testing.simulate_head())

simulate_options(path='/', **kwargs) [source]

Simulates an OPTIONS request to a WSGI application.

(See also: falcon.testing.simulate_options())

simulate_patch(path='/', **kwargs) [source]

Simulates a PATCH request to a WSGI application.

(See also: falcon.testing.simulate_patch())

simulate_post(path='/', **kwargs) [source]

Simulates a POST request to a WSGI application.

(See also: falcon.testing.simulate_post())

simulate_put(path='/', **kwargs) [source]

Simulates a PUT request to a WSGI application.

(See also: falcon.testing.simulate_put())

simulate_request(*args, **kwargs) [source]

Simulates a request to a WSGI application.

Wraps falcon.testing.simulate_request() to perform a WSGI request directly against self.app. Equivalent to:

falcon.testing.simulate_request(self.app, *args, **kwargs)
class falcon.testing.TestCase(methodName='runTest') [source]

Extends unittest to support WSGI functional testing.

Note

If available, uses testtools in lieu of unittest.

This base class provides some extra plumbing for unittest-style test cases, to help simulate WSGI calls without having to spin up an actual web server. Various simulation methods are derived from falcon.testing.TestClient.

Simply inherit from this class in your test case classes instead of unittest.TestCase or testtools.TestCase.

app

A WSGI application to target when simulating requests (default: falcon.API()). When testing your application, you will need to set this to your own instance of falcon.API. For example:

from falcon import testing
import myapp


class MyTestCase(testing.TestCase):
    def setUp(self):
        super(MyTestCase, self).setUp()

        # Assume the hypothetical `myapp` package has a
        # function called `create()` to initialize and
        # return a `falcon.API` instance.
        self.app = myapp.create()


class TestMyApp(MyTestCase):
    def test_get_message(self):
        doc = {u'message': u'Hello world!'}

        result = self.simulate_get('/messages/42')
        self.assertEqual(result.json, doc)
Type: object
setUp() [source]

Hook method for setting up the test fixture before exercising it.

class falcon.testing.SimpleTestResource(status=None, body=None, json=None, headers=None) [source]

Mock resource for functional testing of framework components.

This class implements a simple test resource that can be extended as needed to test middleware, hooks, and the Falcon framework itself.

Only noop on_get() and on_post() responders are implemented; when overriding these, or adding additional responders in child classes, they can be decorated with the falcon.testing.capture_responder_args() hook in order to capture the req, resp, and params arguments that are passed to the responder. Responders may also be decorated with the falcon.testing.set_resp_defaults() hook in order to set resp properties to default status, body, and header values.

Keyword Arguments:
  • status (str) – Default status string to use in responses
  • body (str) – Default body string to use in responses
  • json (JSON serializable) – Default JSON document to use in responses. Will be serialized to a string and encoded as UTF-8. Either json or body may be specified, but not both.
  • headers (dict) – Default set of additional headers to include in responses
called

Whether or not a req/resp was captured.

Type: bool
captured_req

The last Request object passed into any one of the responder methods.

Type: falcon.Request
captured_resp

The last Response object passed into any one of the responder methods.

Type: falcon.Response
captured_kwargs

The last dictionary of kwargs, beyond req and resp, that were passed into any one of the responder methods.

Type: dict
class falcon.testing.StartResponseMock [source]

Mock object representing a WSGI start_response callable.

call_count

Number of times start_response was called.

Type: int
status

HTTP status line, e.g. ‘785 TPS Cover Sheet not attached’.

Type: str
headers

Raw headers list passed to start_response, per PEP-333.

Type: list
headers_dict

Headers as a case-insensitive dict-like object, instead of a list.

Type: dict
falcon.testing.capture_responder_args(req, resp, resource, params) [source]

Before hook for capturing responder arguments.

Adds the following attributes to the hooked responder’s resource class:

  • captured_req
  • captured_resp
  • captured_kwargs
falcon.testing.rand_string(min, max) [source]

Returns a randomly-generated string, of a random length.

Parameters:
  • min (int) – Minimum string length to return, inclusive
  • max (int) – Maximum string length to return, inclusive
falcon.testing.create_environ(path='/', query_string='', protocol='HTTP/1.1', scheme='http', host='falconframework.org', port=None, headers=None, app='', body='', method='GET', wsgierrors=None, file_wrapper=None, remote_addr=None) [source]

Creates a mock PEP-3333 environ dict for simulating WSGI requests.

Keyword Arguments:
  • path (str) – The path for the request (default ‘/’)
  • query_string (str) – The query string to simulate, without a leading ‘?’ (default ‘’)
  • protocol (str) – The HTTP protocol to simulate (default ‘HTTP/1.1’). If set to ‘HTTP/1.0’, the Host header will not be added to the environment.
  • scheme (str) – URL scheme, either ‘http’ or ‘https’ (default ‘http’)
  • host (str) – Hostname for the request (default ‘falconframework.org’)
  • port (str) – The TCP port to simulate. Defaults to the standard port used by the given scheme (i.e., 80 for ‘http’ and 443 for ‘https’).
  • headers (dict) – Headers as a dict or an iterable yielding (key, value) tuple’s
  • app (str) – Value for the SCRIPT_NAME environ variable, described in PEP-333: ‘The initial portion of the request URL’s “path” that corresponds to the application object, so that the application knows its virtual “location”. This may be an empty string, if the application corresponds to the “root” of the server.’ (default ‘’)
  • body (str) – The body of the request (default ‘’). Accepts both byte strings and Unicode strings. Unicode strings are encoded as UTF-8 in the request.
  • method (str) – The HTTP method to use (default ‘GET’)
  • wsgierrors (io) – The stream to use as wsgierrors (default sys.stderr)
  • file_wrapper – Callable that returns an iterable, to be used as the value for wsgi.file_wrapper in the environ.
  • remote_addr (str) – Remote address for the request (default ‘127.0.0.1’)
falcon.testing.redirected(stdout=<_io.TextIOWrapper name='<stdout>' mode='w' encoding='UTF-8'>, stderr=<_io.TextIOWrapper name='<stderr>' mode='w' encoding='UTF-8'>) [source]

A context manager to temporarily redirect stdout or stderr

e.g.:

with redirected(stderr=os.devnull):
falcon.testing.closed_wsgi_iterable(iterable) [source]

Wraps an iterable to ensure its close() method is called.

Wraps the given iterable in an iterator utilizing a for loop as illustrated in the PEP-3333 server/gateway side example. Finally, if the iterable has a close() method, it is called upon exception or exausting iteration.

Furthermore, the first bytestring yielded from iteration, if any, is prefetched before returning the wrapped iterator in order to ensure the WSGI start_response function is called even if the WSGI application is a generator.

Parameters: iterable (iterable) – An iterable that yields zero or more bytestrings, per PEP-3333
Returns: An iterator yielding the same bytestrings as iterable
Return type: iterator

© 2019 by Falcon contributors
Licensed under the Apache License, Version 2.0.
https://falcon.readthedocs.io/en/2.0.0/api/testing.html