Tools/QueueStatusServer/handlers/recentstatus.py

# Copyright (C) 2009 Google Inc. All rights reserved.
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import datetime

from google.appengine.ext import webapp
from google.appengine.ext.webapp import template

from model.queues import Queue
from model.queuestatus import QueueStatus
from model.workitems import WorkItems


class QueueBubble(object):
    """View support class for recentstatus.html"""
    def __init__(self, queue):
        self._queue = queue
        self._work_items = queue.work_items()
        self._last_status = QueueStatus.all().filter("queue_name =", queue.name()).order("-date").get()

    # FIXME: name and display_name should be replaced by a .queue() accessor.
    def name(self):
        return self._queue.name()

    def display_name(self):
        return self._queue.display_name()

    def _last_status_date(self):
        if not self._last_status:
            return None
        return self._last_status.date

    def last_heard_from(self):
        if not self._work_items:
            return self._last_status_date()
        return max(self._last_status_date(), self._work_items.date)

    def is_alive(self):
        if not self.last_heard_from():
            return False
        return self.last_heard_from() > (datetime.datetime.now() - datetime.timedelta(minutes=30))

    def status_class(self):
        if not self.is_alive():
            return "dead"
        if self.pending_items_count() > 1:
            return "behind"
        return "alive"

    def status_text(self):
        if not self._work_items:
            return "Offline"
        if not self._work_items.item_ids:
            return "Idle"
        return self._last_status.message

    def pending_items_count(self):
        if not self._work_items:
            return 0
        return len(self._work_items.item_ids)


class QueuesOverview(webapp.RequestHandler):

    def get(self):
        template_values = {
            "queues": [QueueBubble(queue) for queue in Queue.all()],
        }
        self.response.out.write(template.render("templates/recentstatus.html", template_values))