Index: third_party/logilab/common/tasksqueue.py |
diff --git a/third_party/logilab/common/tasksqueue.py b/third_party/logilab/common/tasksqueue.py |
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+# copyright 2003-2011 LOGILAB S.A. (Paris, FRANCE), all rights reserved. |
+# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr |
+# |
+# This file is part of logilab-common. |
+# |
+# logilab-common is free software: you can redistribute it and/or modify it under |
+# the terms of the GNU Lesser General Public License as published by the Free |
+# Software Foundation, either version 2.1 of the License, or (at your option) any |
+# later version. |
+# |
+# logilab-common is distributed in the hope that it will be useful, but WITHOUT |
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
+# FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more |
+# details. |
+# |
+# You should have received a copy of the GNU Lesser General Public License along |
+# with logilab-common. If not, see <http://www.gnu.org/licenses/>. |
+"""Prioritized tasks queue""" |
+ |
+__docformat__ = "restructuredtext en" |
+ |
+from bisect import insort_left |
+from Queue import Queue |
+ |
+LOW = 0 |
+MEDIUM = 10 |
+HIGH = 100 |
+ |
+PRIORITY = { |
+ 'LOW': LOW, |
+ 'MEDIUM': MEDIUM, |
+ 'HIGH': HIGH, |
+ } |
+REVERSE_PRIORITY = dict((values, key) for key, values in PRIORITY.iteritems()) |
+ |
+ |
+ |
+class PrioritizedTasksQueue(Queue): |
+ |
+ def _init(self, maxsize): |
+ """Initialize the queue representation""" |
+ self.maxsize = maxsize |
+ # ordered list of task, from the lowest to the highest priority |
+ self.queue = [] |
+ |
+ def _put(self, item): |
+ """Put a new item in the queue""" |
+ for i, task in enumerate(self.queue): |
+ # equivalent task |
+ if task == item: |
+ # if new task has a higher priority, remove the one already |
+ # queued so the new priority will be considered |
+ if task < item: |
+ item.merge(task) |
+ del self.queue[i] |
+ break |
+ # else keep it so current order is kept |
+ task.merge(item) |
+ return |
+ insort_left(self.queue, item) |
+ |
+ def _get(self): |
+ """Get an item from the queue""" |
+ return self.queue.pop() |
+ |
+ def __iter__(self): |
+ return iter(self.queue) |
+ |
+ def remove(self, tid): |
+ """remove a specific task from the queue""" |
+ # XXX acquire lock |
+ for i, task in enumerate(self): |
+ if task.id == tid: |
+ self.queue.pop(i) |
+ return |
+ raise ValueError('not task of id %s in queue' % tid) |
+ |
+class Task(object): |
+ def __init__(self, tid, priority=LOW): |
+ # task id |
+ self.id = tid |
+ # task priority |
+ self.priority = priority |
+ |
+ def __repr__(self): |
+ return '<Task %s @%#x>' % (self.id, id(self)) |
+ |
+ def __cmp__(self, other): |
+ return cmp(self.priority, other.priority) |
+ |
+ def __lt__(self, other): |
+ return self.priority < other.priority |
+ |
+ def __eq__(self, other): |
+ return self.id == other.id |
+ |
+ def merge(self, other): |
+ pass |