Tools/QueueStatusServer/handlers/releaselock.py

# Copyright (C) 2014 Apple Inc. All rights reserved.
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from google.appengine.ext import webapp, db
from google.appengine.ext.webapp import template

from config.queues import work_item_lock_timeout
from handlers.updatebase import UpdateBase
from model.queues import Queue


class ReleaseLock(UpdateBase):
    def get(self):
        self.response.out.write(template.render("templates/releaselock.html", {"timeout": work_item_lock_timeout}))

    def post(self):
        queue_name = self.request.get("queue_name")
        # FIXME: This queue lookup should be shared between handlers.
        queue = Queue.queue_with_name(queue_name)
        if not queue:
            self.error(404)
            return

        attachment_id = self._int_from_request("attachment_id")
        queue.active_work_items().expire_item(attachment_id)

        # ReleaseLock is used when a queue neither succeeded nor failed, so it silently releases the patch.
        # Let's try other patches before retrying this one, in the interest of fairness, and also because
        # another patch could be posted to address queue problems.
        queue.work_items().move_to_end(attachment_id)