Created
April 24, 2019 13:14
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Cache function results on the instance.
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| """ | |
| @author: arkanister; | |
| """ | |
| def cache_it(method=None, name=None): | |
| """ | |
| Decorator to cache a function result in the class. | |
| Using this is expected that the function can only be called once by instance, | |
| which means that the second time the function is called, the cached result | |
| will be displayed instead process the content again. | |
| IMPORTANT: It must be only used in class methods. | |
| Args: | |
| method (required) - Method to be decorated. | |
| name (string, optional) - Property name to store the cached value on | |
| the class, the prefix _cached_ will be added to this name. In case None | |
| value the name of the function will be considered. | |
| Returns: | |
| decorated function. | |
| Usage: | |
| >>> @cache_it(name='name') | |
| >>> def get_name(self): | |
| >>> ... | |
| or | |
| >>> @cache_it | |
| >>> def get_name(self): | |
| >>> ... | |
| """ | |
| def wrapper(func): | |
| # get the property name to store the | |
| # function result. | |
| prop = name or func.__name__ | |
| prop = '_cached_%s' % prop | |
| def wrap(self, *args, **kwargs): | |
| if not hasattr(self, prop): | |
| # if the property does not exists yet, | |
| # call the function to get the result and store, | |
| # it result in the property. | |
| setattr(self, prop, func(self, *args, **kwargs)) | |
| # return the cached result. | |
| return getattr(self, prop) | |
| return wrap | |
| if callable(method): | |
| # just in case of `@cache_it` definition. | |
| return wrapper(method) | |
| # return the decorated function. | |
| return wrapper |
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