# -*- coding: utf-8 -*-

# Open Source Initiative OSI - The MIT License (MIT):Licensing

#

# The MIT License (MIT)

# Copyright (c) 2012 DotCloud Inc ([email protected])

#

# Permission is hereby granted, free of charge, to any person obtaining a copy of

# this software and associated documentation files (the "Software"), to deal in

# the Software without restriction, including without limitation the rights to

# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies

# of the Software, and to permit persons to whom the Software is furnished to do

# so, subject to the following conditions:

#

# The above copyright notice and this permission notice shall be included in all

# copies or substantial portions of the Software.

#

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

# SOFTWARE.

import time

import gevent.pool

import gevent.queue

import gevent.event

import gevent.local

import gevent.coros

from .exceptions import *

class HeartBeatOnChannel(object):

def __init__(self, channel, freq=5, passive=False):

self._channel = channel

self._heartbeat_freq = freq

self._input_queue = gevent.queue.Queue(maxsize=0)

self._remote_last_hb = None

self._lost_remote = False

self._recv_task = gevent.spawn(self._recver)

self._heartbeat_task = None

self._parent_coroutine = gevent.getcurrent()

self._compat_v2 = None

if not passive:

self._start_heartbeat()

@property

def recv_is_available(self):

return self._channel.recv_is_available

def __del__(self):

self.close()

def close(self):

if self._heartbeat_task is not None:

self._heartbeat_task.kill()

self._heartbeat_task = None

if self._recv_task is not None:

self._recv_task.kill()

self._recv_task = None

if self._channel is not None:

self._channel.close()

self._channel = None

def _heartbeat(self):

while True:

gevent.sleep(self._heartbeat_freq)

if self._remote_last_hb is None:

self._remote_last_hb = time.time()

if time.time() > self._remote_last_hb + self._heartbeat_freq * 2:

self._lost_remote = True

gevent.kill(self._parent_coroutine,

self._lost_remote_exception())

break

self._channel.emit('_zpc_hb', (0,)) # 0 -> compat with protocol v2

def _start_heartbeat(self):

if self._heartbeat_task is None and self._heartbeat_freq is not None:

self._heartbeat_task = gevent.spawn(self._heartbeat)

def _recver(self):

while True:

event = self._channel.recv()

if self._compat_v2 is None:

self._compat_v2 = event.header.get('v', 0) < 3

if event.name == '_zpc_hb':

self._remote_last_hb = time.time()

self._start_heartbeat()

if self._compat_v2:

event.name = '_zpc_more'

self._input_queue.put(event)

else:

self._input_queue.put(event)

def _lost_remote_exception(self):

return LostRemote('Lost remote after {0}s heartbeat'.format(

self._heartbeat_freq * 2))

def create_event(self, name, args, xheader={}):

if self._compat_v2 and name == '_zpc_more':

name = '_zpc_hb'

return self._channel.create_event(name, args, xheader)

def emit_event(self, event):

if self._lost_remote:

raise self._lost_remote_exception()

self._channel.emit_event(event)

def emit(self, name, args, xheader={}):

event = self.create_event(name, args, xheader)

self.emit_event(event)

def recv(self, timeout=None):

if self._lost_remote:

raise self._lost_remote_exception()

try:

event = self._input_queue.get(timeout=timeout)

except gevent.queue.Empty:

raise TimeoutExpired(timeout)

return event

@property

def channel(self):

return self._channel

@property

def context(self):

return self._channel.context