Introduction

This package provides a simple decorator to help synchronize methods across threads, to avoid problems of concurrent access.

It can be used like this:

from threading import Lock
from plone.synchronize import synchronized

class StupidStack(object):

    _elements = [] # not thread safe
    _lock = Lock()

    @synchronized(_lock)
    def push(self, item):
        self._elements.append(item)

    @synchronized(_lock)
    def pop(self):
        last = self._elements[-1]
        del self._elements[-1]
        return last

The decorator takes care of calling lock.acquire() just before the method is executed, and lock.release() just after. If an exception is raised in the method, the lock will still be released.

Changelog