Firewall on Demand

from gevent import monkey

monkey.patch_all()

from gevent.pool import Pool

import json

import uuid

import simplejson

import datetime

from django.shortcuts import render_to_response

from django.template.loader import render_to_string

from django.http import HttpResponse

from gevent.event import Event

from django.conf import settings

from django.views.decorators.csrf import csrf_exempt

from flowspy.utils import beanstalkc

import logging

FORMAT = '%(asctime)s %(levelname)s: %(message)s'

logging.basicConfig(format=FORMAT)

logger = logging.getLogger(__name__)

logger.setLevel(logging.DEBUG)

def create_message(body, user):

    data = {'id': str(uuid.uuid4()), 'body': body, 'user':user}

    data['html'] = render_to_string('poll_message.html', dictionary={'message': data})

    return data

def json_response(value, **kwargs):

    kwargs.setdefault('content_type', 'text/javascript; charset=UTF-8')

    return HttpResponse(simplejson.dumps(value), **kwargs)

class Msgs(object):

    cache_size = 200

    def __init__(self):

        self.user_cache = {}

        self.user_cursor = {}

        self.cache = []

        self.new_message_event = None

        self.new_message_user_event = {}

    def main(self, request):

        if self.user_cache:

            request.session['cursor'] = self.user_cache[-1]['id']

        return render_to_response('poll.html', {'messages': self.user_cache})

    @csrf_exempt

    def message_existing(self, request):

        try:

            user = request.user.username

        except:

            user = None

        self.new_message_user_event[user] = Event()

        try:

            if self.user_cache[user]:

                self.user_cursor[user] = self.user_cache[user][-1]['id']

        except:

            self.user_cache[user] = []

            self.user_cursor[user] = ''

        return json_response({'messages': self.user_cache[user]})

    @csrf_exempt

    def message_new(self, mesg=None):

        if mesg:

            message = mesg['message']

            user = mesg['username']

            now = datetime.datetime.now()

            msg = create_message("[%s]: %s"%(now.strftime("%Y-%m-%d %H:%M:%S"),message), user)

        try:

            isinstance(self.user_cache[user], list)

        except:

            self.user_cache[user] = []

        self.user_cache[user].append(msg)

        if self.user_cache[user][-1] == self.user_cache[user][0]: 

            self.user_cursor[user] = self.user_cache[user][-1]['id']

        else:

            self.user_cursor[user] = self.user_cache[user][-2]['id']

#        self.cache.append(msg)

        if len(self.user_cache[user]) > self.cache_size:

            self.user_cache[user] = self.user_cache[user][-self.cache_size:]

        self.new_message_user_event[user].set()

        self.new_message_user_event[user].clear()

        return json_response(msg)

    @csrf_exempt

    def message_updates(self, request):

        cursor = {}

        try:

            user = request.user.username

        except:

            user = None

        cursor[user] = self.user_cursor[user]

        try:

            if not isinstance(self.user_cache[user], list):

                self.user_cache[user] = []

        except:

            self.user_cache[user] = []

        if not self.user_cache[user] or cursor[user] == self.user_cache[user][-1]['id']:

            self.new_message_user_event[user].wait()

#            self.new_message_event.wait()

#        assert cursor[user] != self.user_cache[user][-1]['id'], cursor[user]

        try:

            for index, m in enumerate(self.user_cache[user]):

                if m['id'] == cursor[user]:

                    return json_response({'messages': self.user_cache[user][index + 1:]})

            return json_response({'messages': self.user_cache[user]})

        finally:

            if self.user_cache[user]:

                self.user_cursor[user] = self.user_cache[user][-1]['id']

#            else:

#                request.session.pop('cursor', None)

    def monitor_polls(self, polls=None):

        b = beanstalkc.Connection()

        b.watch(settings.POLLS_TUBE)

        while True:

            job = b.reserve()

            print job.body

            msg = json.loads(job.body)

            job.bury()

            self.message_new(msg)

    def start_polling(self):

        logger.info("Start Polling")

        p = Pool(10)

        while True:

            p.spawn(self.monitor_polls)

msgs = Msgs()

main = msgs.main

message_new = msgs.message_new

message_updates = msgs.message_updates

message_existing = msgs.message_existing

poll = msgs.start_polling

poll()