requests-mock/docs/adapter.rst

Adapter Usage

Creating an Adapter

The standard requests means of using an adapter is to :pyrequests.Session.mount it on a created session. This is not the only way to load the adapter, however the same interactions will be used.

>>> import requests
>>> import requests_mock

>>> session = requests.Session()
>>> adapter = requests_mock.Adapter()
>>> session.mount('mock', adapter)

At this point any requests made by the session to a URI starting with mock:// will be sent to our adapter.

Registering Responses

Responses are registered with the :pyrequests_mock.Adapter.register_uri function on the adapter.

>>> adapter.register_uri('GET', 'mock://test.com', text='Success')
>>> resp = session.get('mock://test.com')
>>> resp.text
'Success'

:pyrequests_mock.Adapter.register_uri takes the HTTP method, the URI and then information that is used to build the response. This information includes:

status_code

The HTTP status response to return. Defaults to 200.

reason

The reason text that accompanies the Status (e.g. 'OK' in '200 OK')

headers

A dictionary of headers to be included in the response.

To specify the body of the response there are a number of options that depend on the format that you wish to return.

json

A python object that will be converted to a JSON string.

text

A unicode string. This is typically what you will want to use for regular textual content.

content

A byte string. This should be used for including binary data in responses.

body

A file like object that contains a .read() function.

raw

A prepopulated :pyurllib3.response.HTTPResponse to be returned.

These options are named to coincide with the parameters on a :pyrequests.Response object. For example:

>>> adapter.register_uri('GET', 'mock://test.com/1', json={'a': 'b'}, status_code=200)
>>> resp = session.get('mock://test.com/1')
>>> resp.json()
{'a': 'b'}

>>> adapter.register_uri('GET', 'mock://test.com/2', text='Not Found', status_code=404)
>>> resp = session.get('mock://test.com/2')
>>> resp.text
'Not Found'
>>> resp.status_code
404

It only makes sense to provide at most one body element per response.

Dynamic Response

A callback can be provided in place of any of the body elements. Callbacks must be a function in the form of

def callback(request, context):

and return a value suitable to the body element that was specified. The elements provided are:

request

The :pyrequests.Request object that was provided.

context

An object containing the collected known data about this response.

The available properties on the context are:

headers

The dictionary of headers that are to be returned in the response.

status_code

The status code that is to be returned in the response.

reason

The string HTTP status code reason that is to be returned in the response.

These parameters are populated initially from the variables provided to the :pyrequests_mock.Adapter.register_uri function and if they are modified on the context object then those changes will be reflected in the response.

>>> def text_callback(request, context):
...     context.status_code = 200
...     context.headers['Test1'] = 'value1'
...     return 'response'
...
>>> adapter.register_uri('GET',
...                      'mock://test.com/3',
...                      text=text_callback,
...                      headers={'Test2': 'value2'},
...                      status_code=400)
>>> resp = session.get('mock://test.com/3')
>>> resp.status_code, resp.headers, resp.text
(200, {'Test1': 'value1', 'Test2': 'value2'}, 'response')

Response Lists

Multiple responses can be provided to be returned in order by specifying the keyword parameters in a list. If the list is exhausted then the last response will continue to be returned.

>>> adapter.register_uri('GET', 'mock://test.com/4', [{'text': 'resp1', 'status_code': 300},
...                                                   {'text': 'resp2', 'status_code': 200}])
>>> resp = session.get('mock://test.com/4')
>>> (resp.status_code, resp.text)
(300, 'resp1')
>>> resp = session.get('mock://test.com/4')
>>> (resp.status_code, resp.text)
(200, 'resp2')
>>> resp = session.get('mock://test.com/4')
>>> (resp.status_code, resp.text)
(200, 'resp2')