Using gossip for objectmethods

[eplaut]

how can I use gossip for objectmethods

>>> import gossip
>>> class MyClass(object):
...     def trigger(self):
...         gossip.trigger('my_hook')
...     @gossip.register('my_hook')
...     def my_func(self):
...         print 42
... 
>>> my_object = MyClass()
>>> my_object.trigger()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 3, in trigger
  File "/home/eli/qa/.venv/local/lib/python2.7/site-packages/gossip/hooks.py", line 189, in trigger
    trigger_with_tags(hook_name, kwargs, None)
  File "/home/eli/qa/.venv/local/lib/python2.7/site-packages/gossip/hooks.py", line 199, in trigger_with_tags
    hook.trigger(kwargs or {}, tags)
  File "/home/eli/qa/.venv/local/lib/python2.7/site-packages/gossip/hooks.py", line 152, in trigger
    exception_policy.handle_exception(ctx, exc_info)
  File "/home/eli/qa/.venv/local/lib/python2.7/site-packages/gossip/exception_policy.py", line 29, in handle_exception
    reraise(exc_info[0], exc_info[1], exc_info[2])
  File "/home/eli/qa/.venv/local/lib/python2.7/site-packages/gossip/hooks.py", line 169, in _call_registration
    registration(**kwargs)  # pylint: disable=star-args
  File "/home/eli/qa/.venv/local/lib/python2.7/site-packages/gossip/registration.py", line 70, in __call__
    return self.func(*args, **kwargs)
TypeError: my_func() takes exactly 1 argument (0 given)

since the self parameter is not sent

[edouardpoitras]

If you're just using static methods and aren't making use of the instance variable 'self', then you can try removing it as a parameter entirely:

import gossip
class MyClass(object):
    def trigger(self):
        gossip.trigger('my_hook')
    @gossip.register('my_hook')
    def my_func():
        print 42

Although presumably your my_func needs access to the object instance or you wouldn't be using object oriented code :)
The only way I got that working was by re-naming the self parameter:

import gossip
class Test:
    def hello(self):
        self.message = 'Hello World!'
        gossip.trigger('hello_world', itself=self)
    @gossip.register('hello_world')
    def world(itself):
        print(itself.message)
test = Test()
test.hello()
# Prints 'Hello World!'

However, I may be missing something. I'm not terribly familiar with the code.

Edit: You of course would need to pass an object instance when triggering that hook from outside the class.

[vmalloc]

Registering class methods isn't supported because gossip doesn't know which instance to call...

You can easily achieve a similar result by:

class Blap(object):
    def callback(self, a, b, c):
        pass

obj = Blap()
gossip.register(obj.callback, 'some_hook')