This decorator means thar your method will not mofidy business objects. Like a get method from a Wiki class. Therefore, this method will not generate a log entry at coopy actions log:
from coopy.decorators import readonly
@readonly
def get_page(self, id):
if id in self.pages:
return self.pages[id]
else:
return None
How coopy assures thread-safety? By synchronizing method invocations using a reetrant lock.
This decorator provides a means of leaving the thread safety in your hands via the @unlocked decorator. Using this decorator, you should implement concurrency mechanism by yourself.
Default behaviour is to log on disk, even if your code raises an exception.
If your ‘business’ method raises an exception and your method is decoreted by @abort_exception, this execution will not be logged at disk. This means that during restore process, this invocation that raised an exception will not be re-executed:
from coopy.decorators import abort_exception
@abort_exception
def create_page(self, wikipage):
page = None
wikipage.last_modify = coopy.clock.now()
if wikipage.id in self.pages:
page = self.pages[wikipage.id]
if not page:
self.pages[wikipage.id] = wikipage
raise Exception('Exemple error')
else:
self.update_page(wikipage.id, wikipage.content)
Restore process will not execute this method because it wasn’t logged at disk.