At the command line:
$ pip install fqn-decoratorsBy extending the ~Decorator class you can create simple decorators. Implement the ~Decorator.before and/or ~Decorator.after methods to perform actions before or after execution of the decorated item. The ~Decorator.before method can access the arguments of the decorated item by changing the ~Decorator.args and ~Decorator.kwargs attributes. The ~Decorator.after method can access or change the result using the ~Decorator.result attribute. The ~Decorator.exception method can be used for do something with an Exception that has been raised. In all three methods the ~Decorator.fqn and ~Decorator.func attributes are available.
Create a simple decorator:
import fqn_decorators
import time
class time_it(fqn_decorators.Decorator):
def before(self):
self.start = time.time()
def after(self):
duration = time.time() - self.start
print("{0} took {1} seconds".format(self.fqn, duration))
@time_it
def my_function():
time.sleep(1)
>>>my_function()
__main__.my_function took 1.00293397903 secondsIt is also very easy to create a decorator with arguments.
Note
It is not possible to create decorators with non-keyworded arguments. To create a decorator that supports non-keyworded arguments see the Advanced Usage <usage_advanced_non_keyword_decorators> section.
Example:
import fqn_decorators
import time
class threshold(fqn_decorators.Decorator):
def before(self):
self.start = time.time()
def after(self):
duration = time.time() - self.start
treshold = self.params.get('threshold')
if threshold and duration > threshold:
raise Exception('Execution took longer than the threshold')
@threshold(threshold=2)
def my_function():
time.sleep(3)
>>> my_function()
Exception: Execution took longer than the threshold