wifi_monitor.py
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00001 #!/usr/bin/env python
00002 #
00003 # Software License Agreement (BSD License)
00004 #
00005 # Copyright (c) 2010, Willow Garage, Inc.
00006 # All rights reserved.
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00010 # are met:
00011 #
00012 #  * Redistributions of source code must retain the above copyright
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00014 #  * Redistributions in binary form must reproduce the above
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00016 #    disclaimer in the documentation and/or other materials provided
00017 #    with the distribution.
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00022 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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00033 # POSSIBILITY OF SUCH DAMAGE.
00034 
00035 ##\author Kevin Watts
00036 ##\brief Republishes the data from ddwrt/accesspoint onto diagnostics
00037 
00038 from __future__ import with_statement
00039 
00040 PKG = 'pr2_computer_monitor'
00041 import roslib
00042 roslib.load_manifest(PKG)
00043 
00044 import rospy
00045 
00046 import threading
00047 import sys
00048 
00049 from diagnostic_msgs.msg import DiagnosticArray, DiagnosticStatus, KeyValue
00050 from pr2_msgs.msg import AccessPoint
00051 
00052 DIAG_NAME = 'Wifi Status (ddwrt)'
00053 WARN_TIME = 30
00054 ERROR_TIME = 60
00055 
00056 
00057 def wifi_to_diag(msg):
00058     stat = DiagnosticStatus()
00059 
00060     stat.name = DIAG_NAME
00061     stat.level = DiagnosticStatus.OK
00062     stat.message = 'OK'
00063 
00064     stat.values.append(KeyValue(key='ESSID',       value=msg.essid))
00065     stat.values.append(KeyValue(key='Mac Address', value=msg.macaddr))
00066     stat.values.append(KeyValue(key='Signal',      value=str(msg.signal)))
00067     stat.values.append(KeyValue(key='Noise',       value=str(msg.noise)))
00068     stat.values.append(KeyValue(key='Sig/Noise',   value=str(msg.snr)))
00069     stat.values.append(KeyValue(key='Channel',     value=str(msg.channel)))
00070     stat.values.append(KeyValue(key='Rate',        value=msg.rate))
00071     stat.values.append(KeyValue(key='TX Power',    value=msg.tx_power))
00072     stat.values.append(KeyValue(key='Quality',     value=str(msg.quality)))
00073 
00074     return stat
00075 
00076 def mark_diag_stale(diag_stat = None, error = False):
00077     if not diag_stat:
00078         diag_stat = DiagnosticStatus()
00079         diag_stat.message = 'No Updates'
00080         diag_stat.name    = DIAG_NAME
00081     else:
00082         diag_stat.message = 'Updates Stale'
00083 
00084     diag_stat.level = DiagnosticStatus.WARN
00085     if error:
00086         diag_stat.level = DiagnosticStatus.ERROR
00087 
00088     return diag_stat
00089 
00090 class WifiMonitor(object):
00091     def __init__(self):
00092         self._mutex = threading.Lock()
00093         
00094         self._last_msg = None
00095         self._last_update_time = None
00096         self._start_time = rospy.get_time()
00097 
00098         self._diag_pub = rospy.Publisher('/diagnostics', DiagnosticArray)
00099 
00100         self._ddwrt_sub = rospy.Subscriber('ddwrt/accesspoint', AccessPoint, self._cb)
00101 
00102     def _cb(self, msg):
00103         with self._mutex:
00104             self._last_msg = msg
00105             self._last_update_time = rospy.get_time()
00106 
00107     def publish_stats(self):
00108         with self._mutex:
00109             if self._last_msg:
00110                 ddwrt_stat = wifi_to_diag(self._last_msg)
00111 
00112                 update_diff = rospy.get_time() - self._last_update_time
00113                 if update_diff > WARN_TIME:
00114                     ddwrt_stat = mark_diag_stale(ddwrt_stat)
00115                 if (rospy.get_time() - self._last_update_time) > ERROR_TIME:
00116                     ddwrt_stat = mark_diag_stale(ddwrt_stat, True)
00117 
00118                 ddwrt_stat.values.append(KeyValue(key='Time Since Update', value=str(update_diff)))
00119             else:
00120                 error_state = (rospy.get_time() - self._start_time) > ERROR_TIME
00121                 ddwrt_stat = mark_diag_stale(None, error_state)
00122                 ddwrt_stat.values.append(KeyValue(key='Time Since Update', value="N/A"))
00123 
00124         msg = DiagnosticArray()
00125         msg.header.stamp = rospy.get_rostime()
00126         msg.status.append(ddwrt_stat)
00127         
00128         self._diag_pub.publish(msg)
00129 
00130 
00131 if __name__ == '__main__':
00132     try:
00133         rospy.init_node('ddwrt_diag')
00134     except rospy.exceptions.ROSInitException:
00135         print 'Wifi monitor is unable to initialize node. Master may not be running.'
00136         sys.exit(2)
00137         
00138     wifi_monitor = WifiMonitor()
00139     rate = rospy.Rate(1.0)
00140 
00141     try:
00142         while not rospy.is_shutdown():
00143             rate.sleep()
00144             wifi_monitor.publish_stats()
00145     except KeyboardInterrupt:
00146         pass
00147     except Exception, e:
00148         import traceback
00149         traceback.print_exc()
00150 
00151     sys.exit(0)
00152     
00153 
00154             


pr2_computer_monitor
Author(s): Kevin Watts (watts@willowgarage.com)
autogenerated on Thu Jun 6 2019 20:28:51