mitmocker

Mock server for MITM proxy Developed with a focus on two main points:

1. Automatic recording API response for the first request.
2. Support scripting in JSON templates.

Requirements

Mitmocker is a mock server for MITM. Installation of MITM seems to be a good starting point.

brew install mitmproxy

Instalation

pip install git+https://github.com/pykaso/mitmocker

Usage

1. Create a python script with mock server using MITM scripting API.

    from mitmocker import mock, MitmMockServer
    import os
   
    class MinimalMockServer(MitmMockServer): 
   
        def __init__(self):
            super().__init__(os.path.dirname(os.path.realpath(__file__)))
   
        @mock('/api/v1/')
        def mock_all(self, flow):
            return self.get_template()
   
    addons = [
        MinimalMockServer()
    ]
   

2. Run MITM in reverse mode with a created script. This starts the proxy on localhost and default port 8080.

    mitmproxy -s ./mobilemock.py --mode reverse:http://api.servi.ce
   

In this minimal configuration, every first response of request starting with '/api/v1/' is recorded to single file in 'data' subdirectory in the current working directory. When same request is fired and coresponding file exists, the mock server responds with stored file. Point your application to running proxy and start using automagic mocks.

Response modification

Response could be modified in many ways. For example by direct modification of object returned from get_template() function. If conditional response is needed, it's also possible to use a build-in property prevRequestPath or create a custom one.

@mock('/mobile/v1/marketplace/loans/([0-9]+)')
def loan(self, flow):
    loan = self.get_template()

    # test for previous request path
    if self.prevRequestPath == '/mobile/v1/marketplace/reservations/my-reservations':
        # direct template modification
        loan['my-reservations'] = {
            'custom': 'value'
        }
    return loan

Another way is defining variable right in pjson file by closing the name beginning with the $ character between brackets. For example: {{$customVariable}}. The value for the variable defined like this is searched first in the mock server instance variable or in global variables.

In the brackets can be also used python expression like: {{random(1, 100)}}

Result of expression in pjson file could be stored to variable by this simple syntax: {{random(1, 100)||localVariable}}.

In this example, the expression is evaluated and the result is stored to a global variable named localVariable which is used later on the next line.

{
    "balance": {{round(uniform(100, 10000), 2)||localVariable}},
    "balanceRounded": {{round($localVariable)}}
}