Intercept function and method calls
Intercepts allows you to intercept any function call in Python and handle it in any manner you choose. For example, you can pre-process the inputs to a function, or apply post-processing on its output. Intercepts also allows you to completely replace a function with a custom implementation.
>>> increment(41) 42 >>> intercepts.register(increment, handler) >>> increment(41) 40 >>> intercepts.unregister(increment) >>> intercepts.register(increment, handler2) >>> increment(41) 'The answer is: 42' >>> intercepts.unregister_all()
Handler functions receive the intercepted function as their first argument, as well as all of the arguments to the intercepted function.
>>> def handler(func, num): ... result = func(num) ... return num - (result - num) >>> def handler2(func, *args, **kwargs): ... return "The answer is: %s" % func(*args, **kwargs)
The intercepts module also allows intercepting python built-in functions, such as
sorted. For best results, the intercepts module should be the first module imported.
>>> def print_handler(print_func, message): ... return print_func(''.join(reversed(message))) >>> print("Hello world") Hello world >>> intercepts.register(print, print_handler) >>> print("Hello world") dlrow olleH
Intercepts requires python 3.5+. There are currently no additional dependencies.
Intercepts can be installed using
$ pip install intercepts
pip to install the latest version from the github source.
$ pip install -U git+https://github.com/dlshriver/intercepts.git@master
Some documentation is available here.
This software is in early stages of development and may be unstable.
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