class_objectProcessorQueue.py

import Queue
import threading
import time

class ObjectProcessorQueue(Queue.Queue):
    maxSize = 32000000

    def __init__(self):
        Queue.Queue.__init__(self)
        self.sizeLock = threading.Lock()
        self.curSize = 0 # in Bytes. We maintain this to prevent nodes from flooing us with objects which take up too much memory. If this gets too big we'll sleep before asking for further objects.

    def put(self, item, block = True, timeout = None):
        while self.curSize >= self.maxSize:
            time.sleep(1)
        with self.sizeLock:
            self.curSize += len(item[1])
        Queue.Queue.put(self, item, block, timeout)

    def get(self, block = True, timeout = None):
        try:
            item = Queue.Queue.get(self, block, timeout)
        except Queue.Empty as e:
            raise Queue.Empty()
        with self.sizeLock:
            self.curSize -= len(item[1])
        return item