failureaction is a package intended to provide decorators which execute custom actions in case of exceptions. Let's see an example:
First we need an object with some methods. These methods we decorate with the PrintOnFailure-decorator. This simple example decorator prints a given message in case of an exception.
>>> from failureaction import ConflictError
>>> from failureaction import PrintOnFailure
>>> class TestOb(object):
...
... @PrintOnFailure(msg='Some numeric calculation went wrong!')
... def divide(self, a, b):
... return a/b
...
... @PrintOnFailure()
... def doraise(self):
... raise ConflictError
We have two methods. One (divide) does numerical division of two numbers and another raises a custom defined ConflictError. Now let's see the methods in action:
>>> ob = TestOb()
>>> ob.divide(4, 2)
2
>>> ob.divide(42, 0)
Some numeric calculation went wrong!
>>> ob.doraise()
Traceback (most recent call last):
...
ConflictError
The ActionOnFailure decorator provided by the module is intended to be overriden by a custom class. Like this:
>>> from failureaction import ActionOnFailure
>>> class MailOnFailure(ActionOnFailure):
...
... def __init__(self, subject):
... self.subject = subject
...
... def _doaction(self, context, e):
... """ send a mail, if an exception was raised """
... print "Subject:", self.subject
... print e
>>> class TestOb2(object):
...
... @MailOnFailure(subject='An error occured')
... def critical(self):
... import _not_existent_hopefully_
>>> ob2 = TestOb2()
>>> ob2.critical()
Subject: An error occured
No module named _not_existent_hopefully_
Requirements:
· Python
