# -*- coding: utf-8 -*- {{{
# vim: set fenc=utf-8 ft=python sw=4 ts=4 sts=4 et:
#
# Copyright 2017, Battelle Memorial Institute.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# This material was prepared as an account of work sponsored by an agency of
# the United States Government. Neither the United States Government nor the
# United States Department of Energy, nor Battelle, nor any of their
# employees, nor any jurisdiction or organization that has cooperated in the
# development of these materials, makes any warranty, express or
# implied, or assumes any legal liability or responsibility for the accuracy,
# completeness, or usefulness or any information, apparatus, product,
# software, or process disclosed, or represents that its use would not infringe
# privately owned rights. Reference herein to any specific commercial product,
# process, or service by trade name, trademark, manufacturer, or otherwise
# does not necessarily constitute or imply its endorsement, recommendation, or
# favoring by the United States Government or any agency thereof, or
# Battelle Memorial Institute. The views and opinions of authors expressed
# herein do not necessarily state or reflect those of the
# United States Government or any agency thereof.
#
# PACIFIC NORTHWEST NATIONAL LABORATORY operated by
# BATTELLE for the UNITED STATES DEPARTMENT OF ENERGY
# under Contract DE-AC05-76RL01830
# }}}
from __future__ import print_function, absolute_import
import argparse
import errno
import logging
from logging import handlers
import logging.config
from urlparse import urlparse
import os
import sys
import threading
import uuid
import re
import gevent
from gevent.fileobject import FileObject
import zmq
import logging
from zmq.utils import jsonapi
from zmq import SNDMORE, EHOSTUNREACH, ZMQError, EAGAIN, NOBLOCK
_log = logging.getLogger(__name__)
# Optimizing by pre-creating frames
_ROUTE_ERRORS = {
errnum: (zmq.Frame(str(errnum).encode('ascii')),
zmq.Frame(os.strerror(errnum).encode('ascii')))
for errnum in [zmq.EHOSTUNREACH, zmq.EAGAIN]
}
[docs]class ExternalRPCService(object):
"""
Class to manage routing of RPC calls between external platforms and internal agents(peers).
"""
def __init__(self, socket, routing_service, *args, **kwargs):
self._ext_router = routing_service
self._vip_sock = socket
_log.debug("ExternalRPCService")
[docs] def handle_subsystem(self, frames):
"""
EXT_RPC subsystem handler on the server end.
:frames list of frames
:type frames list
"""
response = []
result = None
try:
sender, recipient, proto, usr_id, msg_id, subsystem, op, msg = frames[:9]
except IndexError:
return False
subsystem = bytes(subsystem)
op = bytes(op)
if subsystem == b'external_rpc':
#If operation is to send to external platform
if op == b'send_platform':
result = self._send_to_platform(frames)
#If operation is to send to internal peer, use the internal router socket to send the frames
elif op == b'send_peer':
result = self._send_to_peer(frames)
if not result:
response = result
elif result is not None:
# Form response frame
response = [sender, recipient, proto, usr_id, msg_id, subsystem]
response.append(zmq.Frame(b'request_response'))
response.append(zmq.Frame(bytes(result)))
return response
def _send_to_platform(self, frames):
"""
Send frames to external platform
:param frames: frames following VIP format
:return:
"""
try:
#Extract the frames and reorganize to add external platform and peer information
sender, recipient, proto, usr_id, msg_id, subsystem, op, msg = frames[:9]
msg_data = jsonapi.loads(bytes(msg))
to_platform = msg_data['to_platform']
msg_data['from_platform'] = self._ext_router.my_instance_name()
msg_data['from_peer'] = bytes(sender)
msg = jsonapi.dumps(msg_data)
op = b'send_peer'
frames = [b'', proto, usr_id, msg_id, subsystem, op, msg]
#_log.debug("ROUTER: Sending EXT RernalPC message to: {}".format(to_platform))
#Use external socket to send the message
self._ext_router.send_external(to_platform, frames)
return False
except KeyError as exc:
_log.error("Missing instance name in external RPC message: {}".format(exc))
except IndexError:
_log.error("Invalid EXT RPC message")
def _send_to_peer(self, frames):
"""
Send the external RPC message to local peer
:param frames: Frames following VIP format
:return: frames list
"""
try:
# Extract the frames and reorganize to send to local peer
sender, recipient, proto, usr_id, msg_id, subsystem, op, msg = frames[:9]
msg_data = jsonapi.loads(bytes(msg))
peer = msg_data['to_peer']
frames[0] = bytes(peer)
drop = self._send_internal(frames)
return False
except KeyError as exc:
_log.error("Missing agent name in external RPC message: {}".format(exc))
except IndexError:
_log.error("Invalid EXT RPC message")
def _send_internal(self, frames):
"""
Send message to internal/local peer
:param frames: frames
:return: peer to be dropped if not reachable
"""
drop = []
peer = bytes(frames[0])
# Expecting outgoing frames:
# [RECIPIENT, SENDER, PROTO, USER_ID, MSG_ID, SUBSYS, ...]
try:
# Try sending the message to its recipient
self._vip_sock.send_multipart(frames, flags=NOBLOCK, copy=False)
except ZMQError as exc:
try:
errnum, errmsg = error = _ROUTE_ERRORS[exc.errno]
except KeyError:
error = None
if exc.errno == EHOSTUNREACH:
_log.debug("Host unreachable {}".format(peer))
drop.append(bytes(peer))
elif exc.errno == EAGAIN:
_log.debug("EAGAIN error {}".format(peer))
return drop