src/rocon_gateway/gateway.py

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#!/usr/bin/env python
#
# License: BSD
#   https://raw.github.com/robotics-in-concert/rocon_multimaster/license/LICENSE
#

###############################################################################
# Imports
###############################################################################

import copy
import os
import threading

import rospy
import gateway_msgs.msg as gateway_msgs
import gateway_msgs.srv as gateway_srvs
import rocon_python_comms

from gateway_msgs.msg import RemoteRuleWithStatus as FlipStatus

from . import utils
from . import ros_parameters
#from .watcher_thread import WatcherThread
from .flipped_interface import FlippedInterface
from .public_interface import PublicInterface
from .pulled_interface import PulledInterface
from .master_api import LocalMaster
from .network_interface_manager import NetworkInterfaceManager

###############################################################################
# Thread
###############################################################################


class Gateway(object):

    '''
      Used to synchronise with hubs.
    '''

    def __init__(self, hub_manager, param, unique_name, publish_gateway_info_callback):
        '''
        @param hub_manager : container for all the hubs this gateway connects to
        @type hub_api.HubManmager

        @param param : parameters set by ros_parameters.py
        @type : dictionary of parameter key-value pairs

        @param unique_name : gateway name (param['name']) with unique uuid hash appended

        @param publish_gateway_info_callback : callback for publishing gateway info
        '''
        self.hub_manager = hub_manager
        self.master = None
        # handling slow startup timeout
        while self.master is None:
            try:
                self.master = LocalMaster()
            except rocon_python_comms.NotFoundException as exc:
                rospy.logwarn(str(exc))
                rospy.logwarn("Cannot create Gateway's LocalMaster. Retrying...")
                self.master = None
            rospy.rostime.wallsleep(1)

        self.ip = self.master.get_ros_ip()  # gateway is always assumed to sit on the same ip as the master
        self._param = param
        self._unique_name = unique_name
        self._publish_gateway_info = publish_gateway_info_callback
        default_rule_blacklist = ros_parameters.generate_rules(self._param["default_blacklist"])
        default_rules, all_targets = ros_parameters.generate_remote_rules(self._param["default_flips"])
        self.flipped_interface = FlippedInterface(
            firewall=self._param['firewall'],
            default_rule_blacklist=default_rule_blacklist,
            default_rules=default_rules,
            all_targets=all_targets)
        default_rules, all_targets = ros_parameters.generate_remote_rules(self._param["default_pulls"])
        self.pulled_interface = PulledInterface(default_rule_blacklist=default_rule_blacklist,
                                                default_rules=default_rules,
                                                all_targets=all_targets)
        self.public_interface = PublicInterface(
            default_rule_blacklist=default_rule_blacklist,
            default_rules=ros_parameters.generate_rules(self._param['default_advertisements']))
        if self._param['advertise_all']:
            # no extra blacklist beyond the default (keeping it simple in yaml for now)
            self.public_interface.advertise_all([])

        self.network_interface_manager = NetworkInterfaceManager(self._param['network_interface'])
        # TODO : Use self._param['watch_loop_period'] to set the connection_cache spin freq ( OR directly in connection_cache node ) ?

    def spin(self):
        if not rospy.core.is_initialized():
            raise rospy.exceptions.ROSInitException("client code must call rospy.init_node() first")
        rospy.logdebug("node[%s, %s] entering spin(), pid[%s]", rospy.core.get_caller_id(), rospy.core.get_node_uri(), os.getpid())
        try:
            while not rospy.core.is_shutdown():
                self.update_network_information()
                remote_gateway_hub_index = self.hub_manager.create_remote_gateway_hub_index()

                with self.master.get_connection_state() as connections:
                    self.update_flipped_interface(connections, remote_gateway_hub_index)
                    self.update_public_interface(connections)
                    self.update_pulled_interface(connections, remote_gateway_hub_index)

                registrations = self.hub_manager.get_flip_requests()
                self.update_flipped_in_interface(registrations, remote_gateway_hub_index)
                rospy.rostime.wallsleep(1)
        except KeyboardInterrupt:
            rospy.logdebug("keyboard interrupt, shutting down")
            rospy.core.signal_shutdown('keyboard interrupt')

    def is_connected(self):
        '''
          We often check if we're connected to any hubs often just to ensure we
          don't waste time processing if there is no-one listening.

          @return True if at least one hub is connected, False otherwise
          @rtype Bool
        '''
        return self.hub_manager.is_connected()

    def disengage_hub(self, hub):
        '''
          Disengage from the specified hub. Don't actually need to clean up connections
          here like we do in shutdown - that can be handled from the watcher thread itself.

          @param hub : the hub that will be deleted.
        '''
        self.hub_manager.disengage_hub(hub)
        self._publish_gateway_info()

    ###############################################################################
    # Update interface states (jobs assigned from connection_cache callback thread)
    ###############################################################################

    def update_flipped_interface(self, local_connection_index, remote_gateway_hub_index):
        """
          Process the list of local connections and check against
          the current flip rules and patterns for changes. If a rule
          has become (un)available take appropriate action.

          @param local_connection_index : list of current local connections
          @type : dictionary of ConnectionType.xxx keyed sets of utils.Connections

          @param gateways : list of remote gateway string id's
          @type string
        """
        state_changed = False

        # Get flip status of existing requests, and remove those requests that need to be resent
        flipped_connections = self.flipped_interface.get_flipped_connections()
        for flip in flipped_connections:
            if flip.remote_rule.gateway in remote_gateway_hub_index:
                for hub in remote_gateway_hub_index[flip.remote_rule.gateway]:
                    status = hub.get_flip_request_status(flip.remote_rule)
                    if status == FlipStatus.RESEND:
                        rospy.loginfo("Gateway : resend requested for flip request [%s]%s" %
                                      (flip.remote_rule.gateway, utils.format_rule(flip.remote_rule.rule)))
                        # Remove the flip, so that it will be resent as part of new_flips
                        self.flipped_interface.remove_flip(flip.remote_rule)
                        hub.send_unflip_request(flip.remote_rule.gateway, flip.remote_rule.rule)
                        hub.remove_flip_details(flip.remote_rule.gateway,
                                                flip.remote_rule.rule.name,
                                                flip.remote_rule.rule.type,
                                                flip.remote_rule.rule.node)
                        break

        new_flips, lost_flips = self.flipped_interface.update(
            local_connection_index, remote_gateway_hub_index, self._unique_name, self.master)
        for connection_type in utils.connection_types:
            for flip in new_flips[connection_type]:
                firewall_flag = self.hub_manager.get_remote_gateway_firewall_flag(flip.gateway)
                if firewall_flag:
                    continue
                state_changed = True
                # for actions, need to post flip details here
                connections = self.master.generate_connection_details(flip.rule.type, flip.rule.name, flip.rule.node)
                if (connection_type == gateway_msgs.ConnectionType.ACTION_CLIENT or
                        connection_type == gateway_msgs.ConnectionType.ACTION_SERVER):
                    rospy.loginfo("Gateway : sending flip request [%s]%s" %
                                  (flip.gateway, utils.format_rule(flip.rule)))
                    hub = remote_gateway_hub_index[flip.gateway][0]
                    hub.post_flip_details(flip.gateway, flip.rule.name, flip.rule.type, flip.rule.node)
                    for connection in connections:
                        hub.send_flip_request(flip.gateway, connection)  # flip the individual pubs/subs
                else:
                    for connection in connections:
                        rospy.loginfo("Gateway : sending flip request [%s]%s" %
                                      (flip.gateway, utils.format_rule(flip.rule)))
                        hub = remote_gateway_hub_index[flip.gateway][0]
                        hub.send_flip_request(flip.gateway, connection)
                        hub.post_flip_details(
                            flip.gateway, flip.rule.name, flip.rule.type, flip.rule.node)
            for flip in lost_flips[connection_type]:
                state_changed = True
                rospy.loginfo("Gateway : sending unflip request [%s]%s" % (flip.gateway, utils.format_rule(flip.rule)))
                for hub in remote_gateway_hub_index[flip.gateway]:
                    rule = copy.deepcopy(flip.rule)
                    if hub.send_unflip_request(flip.gateway, rule):
                        # This hub was used to send the original flip request
                        hub.remove_flip_details(flip.gateway, flip.rule.name, flip.rule.type, flip.rule.node)
                        break

        # Update flip status
        flipped_connections = self.flipped_interface.get_flipped_connections()
        # rospy.loginfo("flipped_connections = {}".format(flipped_connections))
        for flip in flipped_connections:
            for hub in remote_gateway_hub_index[flip.remote_rule.gateway]:
                remote_rule = copy.deepcopy(flip.remote_rule)
                remote_rule.rule.node = remote_rule.rule.node.split(",")[0]  # get only node name, the xmlrpc_uri is not serialised
                status = hub.get_flip_request_status(remote_rule)
                if status is not None:
                    flip_state_changed = self.flipped_interface.update_flip_status(flip.remote_rule, status)
                    state_changed = state_changed or flip_state_changed
                    break

        if state_changed:
            self._publish_gateway_info()

    def update_pulled_interface(self, unused_connections, remote_gateway_hub_index):
        """
          Process the list of local connections and check against
          the current pull rules and patterns for changes. If a rule
          has become (un)available take appropriate action.

          This is called by the watcher thread. The remote_gateway_hub_index
          is always a full dictionary of all remote gateway and hub key-value
          pairs - it is only included as an argument here to save
          processing doubly in the watcher thread.

          @param connections : list of current local connections parsed from the master
          @type : dictionary of ConnectionType.xxx keyed lists of utils.Connections

          @param remote_gateway_hub_index : key-value remote gateway name-hub list pairs
          @type dictionary of remote_gateway_name-list of hub_api.Hub objects key-value pairs
        """
        state_changed = False
        remote_connections = {}
        for remote_gateway in remote_gateway_hub_index.keys() + self.pulled_interface.list_remote_gateway_names():
            remote_connections[remote_gateway] = {}
            try:
                for hub in remote_gateway_hub_index[remote_gateway]:
                    remote_connections[remote_gateway].update(hub.get_remote_connection_state(remote_gateway))
            except KeyError:
                pass  # remote gateway no longer exists on the hub network
        new_pulls, lost_pulls = self.pulled_interface.update(remote_connections, self._unique_name)
        for connection_type in utils.connection_types:
            for pull in new_pulls[connection_type]:
                # dig out the corresponding connection (bit inefficient plouging back into this again
                connection = None
                for remote_gateway in remote_connections.keys():
                    for c in remote_connections[remote_gateway][pull.rule.type]:
                        if c.rule.name == pull.rule.name and \
                           c.rule.node == pull.rule.node:
                            connection = c
                            break
                    if connection:
                        break
                # Register this pull
                existing_registration = self.pulled_interface.find_registration_match(
                    pull.gateway, pull.rule.name, pull.rule.node, pull.rule.type)
                if not existing_registration:
                    rospy.loginfo("Gateway : pulling in connection %s[%s]" %
                                  (utils.format_rule(pull.rule), remote_gateway))
                    registration = utils.Registration(connection, pull.gateway)
                    new_registration = self.master.register(registration)
                    if new_registration is not None:
                        self.pulled_interface.registrations[registration.connection.rule.type].append(new_registration)
                        hub = remote_gateway_hub_index[pull.gateway][0]
                        hub.post_pull_details(pull.gateway, pull.rule.name, pull.rule.type, pull.rule.node)
                        state_changed = True
            for pull in lost_pulls[connection_type]:
                # Unregister this pull
                existing_registration = self.pulled_interface.find_registration_match(
                    pull.gateway, pull.rule.name, pull.rule.node, pull.rule.type)
                if existing_registration:
                    rospy.loginfo("Gateway : abandoning pulled connection %s[%s]" % (
                        utils.format_rule(pull.rule), pull.gateway))
                    self.master.unregister(existing_registration)
                    # This code was here, but causing bugs...actually it should never remove details from the hub,
                    # that is the responsibility of the advertising gateway. TODO confirm this.
                    #hub = remote_gateway_hub_index[pull.gateway][0]
                    # if hub:
                    #    hub.remove_pull_details(pull.gateway, pull.rule.name, pull.rule.type, pull.rule.node)
                    self.pulled_interface.registrations[
                        existing_registration.connection.rule.type].remove(existing_registration)
                    state_changed = True
        if state_changed:
            self._publish_gateway_info()

    def update_public_interface(self, local_connection_index):
        """
          Process the list of local connections and check against
          the current rules and patterns for changes. If a rule
          has become (un)available take appropriate action.

          @param local_connection_index : list of current local connections parsed from the master
          @type : { utils.ConnectionType.xxx : utils.Connection[] } dictionaries
        """
        state_changed = False
        # new_conns, lost_conns are of type { gateway_msgs.ConnectionType.xxx : utils.Connection[] }
        new_conns, lost_conns = self.public_interface.update(
            local_connection_index, self.master.generate_advertisement_connection_details)
        # public_interface is of type gateway_msgs.Rule[]
        public_interface = self.public_interface.getInterface()
        for connection_type in utils.connection_types:
            for new_connection in new_conns[connection_type]:
                rospy.loginfo("Gateway : adding connection to public interface %s" %
                              utils.format_rule(new_connection.rule))
                self.hub_manager.advertise(new_connection)
                state_changed = True
            for lost_connection in lost_conns[connection_type]:
                rospy.loginfo("Gateway : removing connection from public interface %s" %
                              utils.format_rule(lost_connection.rule))
                self.hub_manager.unadvertise(lost_connection)
                state_changed = True
        if state_changed:
            self._publish_gateway_info()
        return public_interface

    def update_flipped_in_interface(self, registrations, remote_gateway_hub_index):
        """
          Match the flipped in connections to supplied registrations using
          supplied registrations, flipping and unflipping as necessary.

          @param registrations : registrations (with status) to be processed
          @type list of (utils.Registration, str) where the str contains the status
        """

        hubs = {}
        for gateway in remote_gateway_hub_index:
            for hub in remote_gateway_hub_index[gateway]:
                hubs[hub.uri] = hub

        update_flip_status = {}
        if self.flipped_interface.firewall:
            if len(registrations) != 0:
                rospy.logwarn("Gateway : firewalled, but received flip requests...")
                for (registration, status) in registrations:
                    for hub in remote_gateway_hub_index[registration.remote_gateway]:
                        if hub.uri not in update_flip_status:
                            update_flip_status[hub.uri] = []
                        update_flip_status[hub.uri].append((registration, FlipStatus.BLOCKED))

            # Mark all these registrations as blocked
            for hub_uri, hub in hubs.iteritems():
                if hub_uri in update_flip_status:
                    hub.update_multiple_flip_request_status(update_flip_status[hub_uri])
            return

        state_changed = False

        # Add new registrations
        for (registration, status) in registrations:
            # probably not necessary as the flipping gateway will already check this
            existing_registration = self.flipped_interface.find_registration_match(
                registration.remote_gateway,
                registration.connection.rule.name,
                registration.connection.rule.node,
                registration.connection.rule.type)
            if not existing_registration:
                rospy.loginfo("Gateway : received a flip request %s" % str(registration))
                state_changed = True
                new_registration = self.master.register(registration)
                if new_registration is not None:
                    self.flipped_interface.registrations[registration.connection.rule.type].append(new_registration)
            # Update this flip's status
            if status != FlipStatus.ACCEPTED:
                for hub in remote_gateway_hub_index[registration.remote_gateway]:
                    if hub.uri not in update_flip_status:
                        update_flip_status[hub.uri] = []
                    update_flip_status[hub.uri].append((registration, FlipStatus.ACCEPTED))

        # Update the flip status for newly added registrations
        for hub_uri, hub in hubs.iteritems():
            if hub_uri in update_flip_status:
                hub.update_multiple_flip_request_status(update_flip_status[hub_uri])

        # Remove local registrations that are no longer flipped to this gateway
        local_registrations = copy.deepcopy(self.flipped_interface.registrations)
        for connection_type in utils.connection_types:
            for local_registration in local_registrations[connection_type]:
                matched_registration = None
                for (registration, status) in registrations:
                    if registration.connection == local_registration.connection and \
                       registration.remote_gateway == local_registration.remote_gateway:
                        matched_registration = registration
                        break
                    else:
                        continue
                if matched_registration is None:
                    state_changed = True
                    rospy.loginfo("Gateway : unflipping received flip %s" % str(local_registration))
                    self.master.unregister(local_registration)
                    self.flipped_interface.registrations[connection_type].remove(local_registration)

        if state_changed:
            self._publish_gateway_info()

    def update_network_information(self):
        """
          If we are running over a wired connection, then do nothing.
          If over the wireless, updated data transfer rate and signal strength
          for this gateway on the hub
        """
        statistics = self.network_interface_manager.get_statistics()
        self.hub_manager.publish_network_statistics(statistics)

    ##########################################################################
    # Incoming commands from local system (ros service callbacks)
    ##########################################################################

    # def ros_service_set_watcher_period(self, request):
    #     '''
    #       Configures the watcher period. This is useful to slow/speed up the
    #       watcher loop. Quite often you want it polling quickly early while
    #       configuring connections, but on long loops later when it does not have
    #       to do very much except look for shutdown.
    #
    #       @param request
    #       @type gateway_srvs.SetWatcherPeriodRequest
    #       @return service response
    #       @rtgateway_srvs.srv.SetWatcherPeriodResponse
    #     '''
    #     self.watcher_thread.set_watch_loop_period(request.period)
    #     return gateway_srvs.SetWatcherPeriodResponse(self.watcher_thread.get_watch_loop_period())
    #
    # def ros_subscriber_force_update(self, data):
    #     '''
    #       Trigger a watcher loop update
    #     '''
    #     self.watcher_thread.trigger_update = True

    def ros_service_advertise(self, request):
        '''
          Puts/Removes a number of rules on the public interface watchlist.
          As local rules matching these rules become available/go away,
          the public interface is modified accordingly. A manual update is done
          at the end of the advertise call to quickly capture existing
          rules

          @param request
          @type gateway_srvs.AdvertiseRequest
          @return service response
          @rtgateway_srvs.srv.AdvertiseReponse
        '''
        response = gateway_srvs.AdvertiseResponse()
        try:
            if not request.cancel:
                for rule in request.rules:
                    if not self.public_interface.add_rule(rule):
                        response.result = gateway_msgs.ErrorCodes.ADVERTISEMENT_EXISTS
                        response.error_message = "advertisment rule already exists [%s:(%s,%s)]" % (
                            rule.name, rule.type, rule.node)
            else:
                for rule in request.rules:
                    if not self.public_interface.remove_rule(rule):
                        response.result = gateway_msgs.ErrorCodes.ADVERTISEMENT_NOT_FOUND
                        response.error_message = "advertisment not found [%s:(%s,%s)]" % (
                            rule.name, rule.type, rule.node)
        except Exception as e:
            rospy.logerr("Gateway : unknown advertise error [%s]." % str(e))
            response.result = gateway_msgs.ErrorCodes.UNKNOWN_ADVERTISEMENT_ERROR

        # Let the watcher get on with the update asap
        if response.result == gateway_msgs.ErrorCodes.SUCCESS:
            #self.watcher_thread.trigger_update = True
            self._publish_gateway_info()
        else:
            rospy.logerr("Gateway : %s." % response.error_message)
        response.watchlist = self.public_interface.getWatchlist()
        return response

    def ros_service_advertise_all(self, request):
        """
          Toggles the advertise all mode. If advertising all, an additional
          blacklist parameter can be supplied which includes all the topics that
          will not be advertised/watched for. This blacklist is added to the
          default blacklist of the public interface

          @param request
          @type gateway_srvs.AdvertiseAllRequest
          @return service response
          @rtype gateway_srvs.AdvertiseAllReponse
        """
        response = gateway_srvs.AdvertiseAllResponse()
        try:
            if not request.cancel:
                if not self.public_interface.advertise_all(request.blacklist):
                    response.result = gateway_msgs.ErrorCodes.ADVERTISEMENT_EXISTS
                    response.error_message = "already advertising all."
            else:
                self.public_interface.unadvertise_all()
        except Exception as e:
            response.result = gateway_msgs.ErrorCodes.UNKNOWN_ADVERTISEMENT_ERROR
            response.error_message = "unknown advertise all error [%s]" % (str(e))

        # Let the watcher get on with the update asap
        if response.result == gateway_msgs.ErrorCodes.SUCCESS:
            #self.watcher_thread.trigger_update = True
            self._publish_gateway_info()
        else:
            rospy.logerr("Gateway : %s." % response.error_message)
        response.blacklist = self.public_interface.getBlacklist()
        return response

    def ros_service_flip(self, request):
        """
          Puts flip rules on a watchlist which (un)flips them when they
          become (un)available.

          @param request
          @type gateway_srvs.RemoteRequest
          @return service response
          @rtype gateway_srvs.RemoteResponse
        """
        # could move this below and if any are fails, just abort adding the rules.
        # Check if the target remote gateway is valid.
#         response = self._check_remote_gateways(request.remotes)
#         if response:
#             return response

        response = gateway_srvs.RemoteResponse(gateway_msgs.ErrorCodes.SUCCESS, "")

        # result is currently SUCCESS
        # Process all add/remove flip requests
        if not request.cancel:  # Rule add request
            response = self._add_flip_rules(request.remotes)
        else:  # Rule remove request
            response = self._remove_flip_rules(request.remotes)

        # Post processing
        if response.result == gateway_msgs.ErrorCodes.SUCCESS:
            self._publish_gateway_info()
            #self.watcher_thread.trigger_update = True
        else:
            rospy.logerr("Gateway : %s." % response.error_message)
        return response

    def ros_service_flip_all(self, request):
        """
          Flips everything except a specified blacklist to a particular gateway,
          or if the cancel flag is set, clears all flips to that gateway.

          @param request
          @type gateway_srvs.RemoteAllRequest
          @return service response
          @rtype gateway_srvs.RemoteAllResponse
        """
        response = gateway_srvs.RemoteAllResponse()
        remote_gateway_target_hash_name, response.result, response.error_message = self._ros_service_remote_checks(
            request.gateway)
        if response.result == gateway_msgs.ErrorCodes.SUCCESS:
            if not request.cancel:
                if self.flipped_interface.flip_all(remote_gateway_target_hash_name, request.blacklist):
                    rospy.loginfo("Gateway : flipping all to gateway '%s'" % (remote_gateway_target_hash_name))
                else:
                    response.result = gateway_msgs.ErrorCodes.FLIP_RULE_ALREADY_EXISTS
                    response.error_message = "already flipping all to gateway '%s' " + remote_gateway_target_hash_name
            else:  # request.cancel
                self.flipped_interface.unflip_all(remote_gateway_target_hash_name)
                rospy.loginfo("Gateway : cancelling a previous flip all request [%s]" % (request.gateway))
        if response.result == gateway_msgs.ErrorCodes.SUCCESS:
            self._publish_gateway_info()
            #self.watcher_thread.trigger_update = True
        else:
            rospy.logerr("Gateway : %s." % response.error_message)
        return response

    def ros_service_pull(self, request):
        """
          Puts a single rule on a watchlist and pulls it from a particular
          gateway when it becomes (un)available.

          @param request
          @type gateway_srvs.RemoteRequest
          @return service response
          @rtype gateway_srvs.RemoteResponse
        """
        # could move this below and if any are fails, just abort adding the rules.
        # Check if the target remote gateway is valid.
        response = self._check_remote_gateways(request.remotes)
        if response:
            return response

        response = gateway_srvs.RemoteResponse(gateway_msgs.ErrorCodes.SUCCESS, "")

        # result is currently SUCCESS
        added_rules = []
        for remote in request.remotes:
            if not request.cancel:
                pull_rule = self.pulled_interface.add_rule(remote)
                if pull_rule:
                    added_rules.append(pull_rule)
                    rospy.loginfo("Gateway : added pull rule [%s:(%s,%s)]" %
                                  (pull_rule.gateway, pull_rule.rule.name, pull_rule.rule.type))
                else:
                    response.result = gateway_msgs.ErrorCodes.PULL_RULE_ALREADY_EXISTS
                    response.error_message = "pull rule already exists [%s:(%s,%s)]" % (
                        remote.gateway, remote.rule.name, remote.rule.type)
                    break
            else:  # request.cancel
                for remote in request.remotes:
                    removed_pull_rules = self.pulled_interface.remove_rule(remote)
                    if removed_pull_rules:
                        rospy.loginfo("Gateway : removed pull rule [%s:%s]" % (remote.gateway, remote.rule.name))
        if response.result == gateway_msgs.ErrorCodes.SUCCESS:
            self._publish_gateway_info()
            #self.watcher_thread.trigger_update = True
        else:
            if added_rules:  # completely abort any added rules
                for added_rule in added_rules:
                    self.pulled_interface.remove_rule(added_rule)
            rospy.logerr("Gateway : %s." % response.error_message)
        return response

    def ros_service_pull_all(self, request):
        """
          Pull everything except a specified blacklist from a particular gateway,
          or if the cancel flag is set, clears all pulls from that gateway.

          @param request
          @type gateway_srvs.RemoteAllRequest
          @return service response
          @rtype gateway_srvs.RemoteAllResponse
        """
        response = gateway_srvs.RemoteAllResponse()
        remote_gateway_target_hash_name, response.result, response.error_message = self._ros_service_remote_checks(
            request.gateway)
        if response.result == gateway_msgs.ErrorCodes.SUCCESS:
            if not request.cancel:
                if self.pulled_interface.pull_all(remote_gateway_target_hash_name, request.blacklist):
                    rospy.loginfo("Gateway : pulling all from gateway [%s]" % (request.gateway))
                else:
                    response.result = gateway_msgs.ErrorCodes.FLIP_RULE_ALREADY_EXISTS
                    response.error_message = "already pulling all from gateway [%s] " % (request.gateway)
            else:  # request.cancel
                self.pulled_interface.unpull_all(remote_gateway_target_hash_name)
                rospy.loginfo("Gateway : cancelling a previous pull all request [%s]" % (request.gateway))
        if response.result == gateway_msgs.ErrorCodes.SUCCESS:
            self._publish_gateway_info()
            #self.watcher_thread.trigger_update = True
        else:
            rospy.logerr("Gateway : %s." % response.error_message)
        return response

    def _ros_service_remote_checks(self, gateway):
        """
          Some simple checks when pulling or flipping to make sure that the remote gateway is visible. It
          does a strict check on the hash names first, then falls back to looking for weak matches on the
          human friendly name.

          @param gateway : remote gateway target name (can be hash name, basename or regex pattern)
          @type string
          @return pair of result type and message
          @rtype gateway_msgs.ErrorCodes.xxx, string
        """
        if not self.is_connected():
            return None, gateway_msgs.ErrorCodes.NO_HUB_CONNECTION, "not connected to hub, aborting"
        if gateway == self._unique_name:
            return None, gateway_msgs.ErrorCodes.REMOTE_GATEWAY_SELF_IS_NOT, "gateway cannot flip/pull to itself"
        return gateway, gateway_msgs.ErrorCodes.SUCCESS, ""
#        matches, weak_matches = self.hub_manager.match_remote_gateway_name(gateway)
#        if len(matches) > 1:
#            return None, gateway_msgs.ErrorCodes.REMOTE_GATEWAY_TARGET_HAS_MULTIPLE_MATCHES, \
#                "remote gateway target has multiple matches, invalid [%s][%s]" % (gateway, matches)
#        elif len(matches) == 1:
#            return matches[0], gateway_msgs.ErrorCodes.SUCCESS, ""
# Fallback to checking for weak matches
#        if len(weak_matches) > 1:
#            return None, gateway_msgs.ErrorCodes.REMOTE_GATEWAY_TARGET_HAS_MULTIPLE_MATCHES, \
#                "remote gateway target has multiple matches against hashed names, invalid [%s]" % weak_matches
#        elif len(weak_matches) == 1:
#            return weak_matches[0], gateway_msgs.ErrorCodes.SUCCESS, ""
# Not visible
# return None, gateway_msgs.ErrorCodes.REMOTE_GATEWAY_NOT_VISIBLE, "remote
# gateway is currently not visible on the hubs [%s]" % gateway

    def _check_remote_gateways(self, remotes):
        """
          Check given gateways in remote rules are valid

          :param remotes: remote rules
          :type remotes: gateway_msgs.RemoteRule[]

          :return: whether it is valid, error message if it fails
          :rtypes: None or gateway_srvs.RemoteResponse
        """
        response = gateway_srvs.RemoteResponse()
        for remote in remotes:
            remote.gateway, response.result, response.error_message = self._ros_service_remote_checks(remote.gateway)
            if response.result != gateway_msgs.ErrorCodes.SUCCESS:
                rospy.logerr("Gateway : %s." % response.error_message)
                return response
        return None

    def _add_flip_rules(self, remotes):
        """
          Add given rules into watcher list

          :param remotes: remote rules
          :type remotes: gateway_msgs.RemoteRule[]
          :return: whether it is successful
          :rtypes: gateway_srvs.RemoteResponse
        """
        response = gateway_srvs.RemoteResponse()
        response.result = gateway_msgs.ErrorCodes.SUCCESS

        added_rules = []
        for remote in remotes:
            flip_rule = self.flipped_interface.add_rule(remote)
            if flip_rule:
                added_rules.append(flip_rule)
                rospy.loginfo("Gateway : added flip rule [%s:(%s,%s)]" % (flip_rule.gateway, flip_rule.rule.name, flip_rule.rule.type))
            else:
                response.result = gateway_msgs.ErrorCodes.FLIP_RULE_ALREADY_EXISTS
                response.error_message = "flip rule already exists [%s:(%s,%s)]" % (remote.gateway, remote.rule.name, remote.rule.type)

        if response.result != gateway_msgs.ErrorCodes.SUCCESS:
            # completely abort any added rules
            for added_rule in added_rules:
                self.flipped_interface.remove_rule(added_rule)
        return response

    def _remove_flip_rules(self, remotes):
        """
          remove given rules into watcher list

          :param remotes: remote rules
          :type remotes: gateway_msgs.RemoteRule[]
          :return: whether it is successful
          :rtypes: gateway_srvs.RemoteResponse
        """
        response = gateway_srvs.RemoteResponse()
        response.result = gateway_msgs.ErrorCodes.SUCCESS

        for remote in remotes:
            removed_flip_rules = self.flipped_interface.remove_rule(remote)
            if removed_flip_rules:
                rospy.loginfo("Gateway : removed flip rule [%s:(%s,%s)]" % (remote.gateway, remote.rule.name, remote.rule.type))
        return response