class OwnMasterMonitoring(QtCore.QObject):
'''
A class to monitor the state of the master. Will be used, if no master
discovering is available. On changes the 'state_signal' of type
L{master_discovery_fkie.msg.MasterState} will be emitted.
'''
state_signal = QtCore.Signal(master_discovery_fkie.msg.MasterState)
'''@ivar: a signal to inform the receiver about new master state.
Parameter: L{master_discovery_fkie.msg.MasterState}'''
ROSMASTER_HZ = 1
'''@ivar: the rate to test ROS master for changes.'''
def init(self, monitor_port):
'''
Creates the local monitoring. Call start() to run the local monitoring.
@param monitor_port: the port of the XML-RPC Server created by monitoring class.
@type monitor_port: C{int}
'''
self._master_monitor = MasterMonitor(monitor_port)
self._do_pause = True
# self._local_addr = roslib.network.get_local_address()
# self._masteruri = roslib.rosenv.get_master_uri()
self._masteruri = self._master_monitor.getMasteruri()
self._local_addr = self._master_monitor.getMastername()
self._masterMonitorThread = threading.Thread(target = self.mastermonitor_loop)
self._masterMonitorThread.setDaemon(True)
self._masterMonitorThread.start()
def mastermonitor_loop(self):
'''
The method test periodically the state of the ROS master. The new state will
be published as 'state_signal'.
'''
import os
current_check_hz = OwnMasterMonitoring.ROSMASTER_HZ
while (not rospy.is_shutdown()):
try:
if not self._do_pause:
cputimes = os.times()
cputime_init = cputimes[0] + cputimes[1]
if self._master_monitor.checkState():
mon_state = self._master_monitor.getState()
# publish the new state
state = MasterState(MasterState.STATE_CHANGED,
ROSMaster(str(self._local_addr),
str(self._masteruri),
mon_state.timestamp,
True,
rospy.get_name(),
''.join(['http://', str(self._local_addr),':',str(self._master_monitor.rpcport)])))
self.state_signal.emit(state)
# adapt the check rate to the CPU usage time
cputimes = os.times()
cputime = cputimes[0] + cputimes[1] - cputime_init
if current_check_hz*cputime > 0.4:
current_check_hz = float(current_check_hz)/2.0
elif current_check_hz*cputime < 0.20 and current_check_hz < OwnMasterMonitoring.ROSMASTER_HZ:
current_check_hz = float(current_check_hz)*2.0
except MasterConnectionException, e:
rospy.logwarn("Error while master check loop: %s", str(e))
except RuntimeError, e:
# will thrown on exit of the app while try to emit the signal
rospy.logwarn("Error while master check loop: %s", str(e))
time.sleep(1.0/current_check_hz)
