@@ -49,8 +49,19 @@ import json

 import ina260 # power sensor

 import tmp102 # temperature sensor

+# Import custom libraries

+import smsalert

+

     ### ENVIRONMENT ###

+

 _USER = os.environ['USER']

+_HOSTNAME = os.uname()[1]

+

+    ### SMS RECIPIENTS ###

+

+_SMS_CALLSIGN = '{your callsign}'

+_SMS_PASSCODE = '{your passcode}'

+_SMS_PHONE_NUMBER = '{your phone number}'

     ### SENSOR BUS ADDRESSES ###

@@ -89,11 +100,16 @@ _CHART_WIDTH = 600

 _CHART_HEIGHT = 150

 # chart average line color

 _AVERAGE_LINE_COLOR = '#006600'

+# low voltage alert threshold

+_DEFAULT_CRITICAL_LOW_VOLTAGE = 12.0

    ### GLOBAL VARIABLES ###

-# Container for sensor objects.

-dSensors = {}

+# Sensor instance objects.

+power1 = None

+battemp = None

+ambtemp = None

+sms = None

 # turns on or off extensive debugging messages

 debugMode = False

@@ -107,6 +123,8 @@ chartUpdateInterval = _CHART_UPDATE_INTERVAL

 failedUpdateCount = 0

 # sensor status

 deviceOnline = False

+# sms message sent status

+bSMSmsgSent = False

   ###  PRIVATE METHODS  ###

@@ -182,11 +200,11 @@ def getSensorData(dData):

     dData["time"] = getTimeStamp()

     try:

-        dData["current"] = dSensors['power'].getCurrent()

-        dData["voltage"] = dSensors['power'].getVoltage()

-        dData["power"] = dSensors['power'].getPower()

-        dData["battemp"] = dSensors['battemp'].getTempF()

-        dData["ambtemp"] = dSensors['ambtemp'].getTempF()

+        dData["current"] = power1.getCurrent()

+        dData["voltage"] = power1.getVoltage()

+        dData["power"] =   power1.getPower()

+        dData["battemp"] = battemp.getTempF()

+        dData["ambtemp"] = ambtemp.getTempF()

     except Exception as exError:

         print("%s sensor error: %s" % (getTimeStamp(), exError))

         return False

@@ -196,6 +214,34 @@ def getSensorData(dData):

     return True

 ## end def

+def convertData(dData):

+    """

+    Converts data items and verifies threshold crossings.

+    Parameters: dData - a dictionary object that contains the sensor data

+    Returns: True if successful, False otherwise

+    """

+    global bSMSmsgSent

+

+    if not bSMSmsgSent and dData["voltage"] <= _DEFAULT_CRITICAL_LOW_VOLTAGE:

+        # Format a text alert message.

+        message = "%s %s low voltage alert: %s volts" % \

+                  (getTimeStamp(), _HOSTNAME, dData["voltage"])

+        print(message)

+        # Send the text alert to recipient phone numbers.

+        sms.sendSMS(_SMS_PHONE_NUMBER, message)

+        bSMSmsgSent = True

+    elif bSMSmsgSent and dData["voltage"] > _DEFAULT_CRITICAL_LOW_VOLTAGE:

+        # Format a text alert message.

+        message = "%s %s voltage normal: %s volts" % \

+                  (getTimeStamp(), _HOSTNAME, dData["voltage"])

+        print(message)

+        # Send the text alert to recipient phone numbers.

+        sms.sendSMS(_SMS_PHONE_NUMBER, message)

+        bSMSmsgSent = False

+    ## end if

+    return True

+## end def

+

 def writeOutputFile(dData):

     """

     Write sensor data items to the output data file, formatted as 

@@ -492,13 +538,15 @@ def getCLarguments():

         index += 1

 ##end def

-def main():

+def main_setup():

     """

     Handles timing of events and acts as executive routine managing

     all other functions.

     Parameters: none

     Returns: nothing

     """

+    global power1, battemp, ambtemp, sms

+

     signal.signal(signal.SIGTERM, terminateAgentProcess)

     signal.signal(signal.SIGINT, terminateAgentProcess)

@@ -518,15 +566,15 @@ def main():

         exit(1)

     # Create sensor objects.  This also initializes each sensor.

-    dSensors['power'] = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_NUMBER,

+    power1 = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_NUMBER,

                             debug=debugMode)

-    dSensors['battemp'] = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_NUMBER,

+    battemp = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_NUMBER,

                             debug=debugMode)

-    dSensors['ambtemp'] = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_NUMBER,

+    ambtemp = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_NUMBER,

                             debug=debugMode)

+    # Create instance of SMS alert class

+    sms = smsalert.smsalert(_SMS_CALLSIGN, _SMS_PASSCODE, debug=debugMode)

-    # Enter main loop.

-    main_loop()

 ## end def

 def main_loop():

@@ -550,9 +598,13 @@ def main_loop():

             dData = {}

             # Get the data from the sensors.

-            result =getSensorData(dData)

+            result = getSensorData(dData)

-            # If get data successful, write data to data files.

+            # If get data successful, convert the data and verify thresholds.

+            if result:

+                result = convertData(dData)

+

+            # If convert data successful, write data to data files.

             if result:

                 result = writeOutputFile(dData)

@@ -589,4 +641,5 @@ def main_loop():

 ## end def

 if __name__ == '__main__':

-    main()

+    main_setup()

+    main_loop()

@@ -92,6 +92,9 @@ _AVERAGE_LINE_COLOR = '#006600'

    ### GLOBAL VARIABLES ###

+# Container for sensor objects.

+dSensors = {}

+

 # turns on or off extensive debugging messages

 debugMode = False

 verboseMode = False

@@ -167,7 +170,7 @@ def terminateAgentProcess(signal, frame):

   ###  PUBLIC METHODS  ###

-def getSensorData(dSensors, dData):

+def getSensorData(dData):

     """

     Poll sensors for data. Store the data in a dictionary object for

     use by other subroutines.  The dictionary object passed in should

@@ -504,13 +507,6 @@ def main():

           '%s starting up node power agent process' % \

                   (getTimeStamp())

-    # last time output JSON file updated

-    lastDataRequestTime = -1

-    # last time charts generated

-    lastChartUpdateTime = - 1

-    # last time the rrdtool database updated

-    lastDatabaseUpdateTime = -1

-

     ## Get command line arguments.

     getCLarguments()

@@ -522,7 +518,6 @@ def main():

         exit(1)

     # Create sensor objects.  This also initializes each sensor.

-    dSensors = {}

     dSensors['power'] = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_NUMBER,

                             debug=debugMode)

     dSensors['battemp'] = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_NUMBER,

@@ -530,6 +525,18 @@ def main():

     dSensors['ambtemp'] = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_NUMBER,

                             debug=debugMode)

+    # Enter main loop.

+    main_loop()

+## end def

+

+def main_loop():

+    # last time output JSON file updated

+    lastDataRequestTime = -1

+    # last time charts generated

+    lastChartUpdateTime = - 1

+    # last time the rrdtool database updated

+    lastDatabaseUpdateTime = -1

+

     ### MAIN LOOP ###

     while True:

@@ -543,7 +550,7 @@ def main():

             dData = {}

             # Get the data from the sensors.

-            result =getSensorData(dSensors, dData)

+            result =getSensorData(dData)

             # If get data successful, write data to data files.

             if result:

@@ -579,7 +586,6 @@ def main():

         if remainingTime > 0.0:

             time.sleep(remainingTime)

     ## end while

-    return

 ## end def

 if __name__ == '__main__':

@@ -188,6 +188,8 @@ def getSensorData(dSensors, dData):

         print("%s sensor error: %s" % (getTimeStamp(), exError))

         return False

+    dData['chartUpdateInterval'] = chartUpdateInterval

+

     return True

 ## end def

@@ -212,7 +214,6 @@ def writeOutputFile(dData):

     try:

         for key in dData:

             jsData.update({key:dData[key]})

-        jsData.update({"chartUpdateInterval": chartUpdateInterval})

         sData = "[%s]" % json.dumps(jsData)

     except Exception as exError:

         print("%s writeOutputFile: %s" % (getTimeStamp(), exError))

@@ -253,17 +254,20 @@ def setStatus(updateSuccess):

         if not deviceOnline:

             print('%s device online' % getTimeStamp())

             deviceOnline = True

+        return

     else:

         # The last attempt failed, so update the failed attempts

         # count.

         failedUpdateCount += 1

-    if failedUpdateCount >= _MAX_FAILED_DATA_REQUESTS:

+    if failedUpdateCount == _MAX_FAILED_DATA_REQUESTS:

         # Max number of failed data requests, so set

         # device status to offline.

         setStatusToOffline()

 ##end def

+    ### DATABASE FUNCTIONS ###

+

 def updateDatabase(dData):

     """

     Update the rrdtool database by executing an rrdtool system command.

@@ -289,12 +293,12 @@ def updateDatabase(dData):

         subprocess.check_output(strCmd, shell=True, \

             stderr=subprocess.STDOUT)

     except subprocess.CalledProcessError as exError:

-        print("%s: rrdtool update failed: %s" % \

+        print("%s: rrdtool update: %s" % \

             (getTimeStamp(), exError.output))

         return False

     if verboseMode and not debugMode:

-        print("database updated")

+        print("database update successful")

     return True

 ## end def

@@ -373,7 +377,8 @@ def createGraph(fileName, dataItem, gLabel, gTitle, gStart,

                      stderr=subprocess.STDOUT,   \

                      shell=True)

     except subprocess.CalledProcessError as exError:

-        print("rrdtool graph failed: %s" % (exError.output))

+        print("%s rrdtool graph: %s" % \

+              (getTimeStamp(), exError.output))

         return False

     if verboseMode and not debugMode:

@@ -31,6 +31,8 @@

 #   * v10 released 01 June 2021 by J L Owrey; first release

 #   * v11 released 02 July 2021 by J L Owrey; improved sensor fault

 #     handling; improved code readability

+#   * v12 released 06 July 2021 by J L Owrey; improved debug mode

+#     handling; debug mode state now passed to sensor object constructors

 #

 #2345678901234567890123456789012345678901234567890123456789012345678901234567890

@@ -103,11 +105,6 @@ failedUpdateCount = 0

 # sensor status

 deviceOnline = False

-# Create sensor objects.  This also initialzes each sensor.

-power = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_NUMBER)

-battemp = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_NUMBER)

-ambtemp = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_NUMBER)

-

   ###  PRIVATE METHODS  ###

 def getTimeStamp():

@@ -170,22 +167,23 @@ def terminateAgentProcess(signal, frame):

   ###  PUBLIC METHODS  ###

-def getSensorData(dData):

+def getSensorData(dSensors, dData):

     """

     Poll sensors for data. Store the data in a dictionary object for

     use by other subroutines.  The dictionary object passed in should

     an empty dictionary, i.e., dData = { }.

     Parameters: dData - a dictionary object to contain the sensor data

+                dSensors - a dictionary containing sensor objects

     Returns: True if successful, False otherwise

     """

     dData["time"] = getTimeStamp()

     try:

-        dData["current"] = power.getCurrent()

-        dData["voltage"] = power.getVoltage()

-        dData["power"] = power.getPower()

-        dData["battemp"] = battemp.getTempF()

-        dData["ambtemp"] = ambtemp.getTempF()

+        dData["current"] = dSensors['power'].getCurrent()

+        dData["voltage"] = dSensors['power'].getVoltage()

+        dData["power"] = dSensors['power'].getPower()

+        dData["battemp"] = dSensors['battemp'].getTempF()

+        dData["ambtemp"] = dSensors['ambtemp'].getTempF()

     except Exception as exError:

         print("%s sensor error: %s" % (getTimeStamp(), exError))

         return False

@@ -517,8 +515,18 @@ def main():

               'use createPowerRrd script to ' \

               'create rrdtool database\n')

         exit(1)

- 

-    ## main loop

+

+    # Create sensor objects.  This also initializes each sensor.

+    dSensors = {}

+    dSensors['power'] = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_NUMBER,

+                            debug=debugMode)

+    dSensors['battemp'] = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_NUMBER,

+                            debug=debugMode)

+    dSensors['ambtemp'] = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_NUMBER,

+                            debug=debugMode)

+

+    ### MAIN LOOP ###

+

     while True:

         currentTime = time.time() # get current time in seconds

@@ -530,7 +538,7 @@ def main():

             dData = {}

             # Get the data from the sensors.

-            result =getSensorData(dData)

+            result =getSensorData(dSensors, dData)

             # If get data successful, write data to data files.

             if result:

@@ -29,6 +29,8 @@

 #

 # Revision History

 #   * v10 released 01 June 2021 by J L Owrey; first release

+#   * v11 released 02 July 2021 by J L Owrey; improved sensor fault

+#     handling; improved code readability

 #

 #2345678901234567890123456789012345678901234567890123456789012345678901234567890

@@ -55,7 +57,7 @@ _PWR_SENSOR_ADDR = 0X40

 _BAT_TMP_SENSOR_ADDR = 0x48

 _AMB_TMP_SENSOR_ADDR = 0x4B

 # Set bus selector.

-_BUS_SEL = 1

+_BUS_NUMBER = 1

     ### FILE AND FOLDER LOCATIONS ###

@@ -71,9 +73,12 @@ _RRD_FILE = "/home/%s/database/powerData.rrd" % _USER

     ### GLOBAL CONSTANTS ###

 # sensor data request interval in seconds

-_DEFAULT_DATA_REQUEST_INTERVAL = 2

+_DEFAULT_SENSOR_POLLING_INTERVAL = 2

 # rrdtool database update interval in seconds

 _DATABASE_UPDATE_INTERVAL = 30

+# max number of failed attempts to get sensor data

+_MAX_FAILED_DATA_REQUESTS = 2

+

 # chart update interval in seconds

 _CHART_UPDATE_INTERVAL = 600

 # standard chart width in pixels

@@ -85,19 +90,23 @@ _AVERAGE_LINE_COLOR = '#006600'

    ### GLOBAL VARIABLES ###

-# debug output options

+# turns on or off extensive debugging messages

 debugMode = False

 verboseMode = False

 # frequency of data requests to sensors

-dataRequestInterval = _DEFAULT_DATA_REQUEST_INTERVAL

+dataRequestInterval = _DEFAULT_SENSOR_POLLING_INTERVAL

 # how often charts get updated

 chartUpdateInterval = _CHART_UPDATE_INTERVAL

+# number of failed attempts to get sensor data

+failedUpdateCount = 0

+# sensor status

+deviceOnline = False

-# Define each sensor.  This also initialzes each sensor.

-pwr = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_SEL)

-btmp = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_SEL)

-atmp = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_SEL)

+# Create sensor objects.  This also initialzes each sensor.

+power = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_NUMBER)

+battemp = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_NUMBER)

+ambtemp = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_NUMBER)

   ###  PRIVATE METHODS  ###

@@ -127,21 +136,37 @@ def getEpochSeconds(sTime):

     return tSeconds

 ## end def

-def terminateAgentProcess(signal, frame):

-    """

-    Send a message to the log when the agent process gets killed

-    by the operating system.  Inform downstream clients

-    by removing output data files.

-    Parameters:

-        signal, frame - dummy parameters

-    Returns: nothing

+def setStatusToOffline():

+    """Set the detected status of the device to

+       "offline" and inform downstream clients by removing input

+       and output data files.

+       Parameters: none

+       Returns: nothing

     """

+    global deviceOnline

+

     # Inform downstream clients by removing output data file.

     if os.path.exists(_OUTPUT_DATA_FILE):

        os.remove(_OUTPUT_DATA_FILE)

-    print('%s terminating npw agent process' % getTimeStamp())

+    # If the sensor or  device was previously online, then send

+    # a message that we are now offline.

+    if deviceOnline:

+        print('%s device offline' % getTimeStamp())

+    deviceOnline = False

+##end def

+

+def terminateAgentProcess(signal, frame):

+    """Send a message to log when the agent process gets killed

+       by the operating system.  Inform downstream clients

+       by removing input and output data files.

+       Parameters:

+           signal, frame - dummy parameters

+       Returns: nothing

+    """

+    print('%s terminating agent process' % getTimeStamp())

+    setStatusToOffline()

     sys.exit(0)

-## end def

+##end def

   ###  PUBLIC METHODS  ###

@@ -156,11 +181,11 @@ def getSensorData(dData):

     dData["time"] = getTimeStamp()

     try:

-        dData["current"] = pwr.getCurrent()

-        dData["voltage"] = pwr.getVoltage()

-        dData["power"] = pwr.getPower()

-        dData["battemp"] = btmp.getTempF()

-        dData["ambtemp"] = atmp.getTempF()

+        dData["current"] = power.getCurrent()

+        dData["voltage"] = power.getVoltage()

+        dData["power"] = power.getPower()

+        dData["battemp"] = battemp.getTempF()

+        dData["ambtemp"] = ambtemp.getTempF()

     except Exception as exError:

         print("%s sensor error: %s" % (getTimeStamp(), exError))

         return False

@@ -212,6 +237,35 @@ def writeOutputFile(dData):

     return True

 ## end def

+def setStatus(updateSuccess):

+    """Detect if device is offline or not available on

+       the network. After a set number of attempts to get data

+       from the device set a flag that the device is offline.

+       Parameters:

+           updateSuccess - a boolean that is True if data request

+                           successful, False otherwise

+       Returns: nothing

+    """

+    global failedUpdateCount, deviceOnline

+

+    if updateSuccess:

+        failedUpdateCount = 0

+        # Set status and send a message to the log if the device

+        # previously offline and is now online.

+        if not deviceOnline:

+            print('%s device online' % getTimeStamp())

+            deviceOnline = True

+    else:

+        # The last attempt failed, so update the failed attempts

+        # count.

+        failedUpdateCount += 1

+

+    if failedUpdateCount >= _MAX_FAILED_DATA_REQUESTS:

+        # Max number of failed data requests, so set

+        # device status to offline.

+        setStatusToOffline()

+##end def

+

 def updateDatabase(dData):

     """

     Update the rrdtool database by executing an rrdtool system command.

@@ -439,12 +493,13 @@ def main():

     Parameters: none

     Returns: nothing

     """

-    global dataRequestInterval

-

     signal.signal(signal.SIGTERM, terminateAgentProcess)

     signal.signal(signal.SIGINT, terminateAgentProcess)

-    print('%s starting up node power agent process' % getTimeStamp())

+    # Log agent process startup time.

+    print '===================\n'\

+          '%s starting up node power agent process' % \

+                  (getTimeStamp())

     # last time output JSON file updated

     lastDataRequestTime = -1

@@ -488,6 +543,8 @@ def main():

                 ## Update the round robin database with the parsed data.

                 result = updateDatabase(dData)

+            setStatus(result)

+

         # At the chart generation interval, generate charts.

         if currentTime - lastChartUpdateTime > chartUpdateInterval:

             lastChartUpdateTime = currentTime

@@ -86,15 +86,13 @@ _AVERAGE_LINE_COLOR = '#006600'

    ### GLOBAL VARIABLES ###

 # debug output options

-debugOption = False

-verboseDebug = False

+debugMode = False

+verboseMode = False

 # frequency of data requests to sensors

 dataRequestInterval = _DEFAULT_DATA_REQUEST_INTERVAL

 # how often charts get updated

 chartUpdateInterval = _CHART_UPDATE_INTERVAL

-# last node request time

-lastDataPointTime = -1

 # Define each sensor.  This also initialzes each sensor.

 pwr = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_SEL)

@@ -170,41 +168,6 @@ def getSensorData(dData):

     return True

 ## end def

-def updateDatabase(dData):

-    """

-    Update the rrdtool database by executing an rrdtool system command.

-    Format the command using the data extracted from the sensors.

-    Parameters: dData - dictionary object containing data items to be

-                        written to the rr database file

-    Returns: True if successful, False otherwise

-    """

- 

-    epochTime = getEpochSeconds(dData['time'])

-

-    # Format the rrdtool update command.

-    strFmt = "rrdtool update %s %s:%s:%s:%s:%s:%s"

-    strCmd = strFmt % (_RRD_FILE, epochTime, dData['current'], \

-             dData['voltage'], dData['power'], dData['battemp'], \

-             dData['ambtemp'])

-

-    if verboseDebug:

-        print("%s" % strCmd) # DEBUG

-

-    # Run the command as a subprocess.

-    try:

-        subprocess.check_output(strCmd, shell=True, \

-            stderr=subprocess.STDOUT)

-    except subprocess.CalledProcessError as exError:

-        print("%s: rrdtool update failed: %s" % \

-            (getTimeStamp(), exError.output))

-        return False

-

-    if debugOption and not verboseDebug:

-        print("database updated")

-

-    return True

-## end def

-

 def writeOutputFile(dData):

     """

     Write sensor data items to the output data file, formatted as 

@@ -222,8 +185,8 @@ def writeOutputFile(dData):

     #    * The sensor values

     # Create a JSON formatted string from the sensor data.

+    jsData = json.loads("{}")

     try:

-        jsData = json.loads("{}")

         for key in dData:

             jsData.update({key:dData[key]})

         jsData.update({"chartUpdateInterval": chartUpdateInterval})

@@ -232,7 +195,7 @@ def writeOutputFile(dData):

         print("%s writeOutputFile: %s" % (getTimeStamp(), exError))

         return False

-    if verboseDebug:

+    if debugMode:

         print(sData)

     # Write the JSON formatted data to the output data file.

@@ -249,6 +212,41 @@ def writeOutputFile(dData):

     return True

 ## end def

+def updateDatabase(dData):

+    """

+    Update the rrdtool database by executing an rrdtool system command.

+    Format the command using the data extracted from the sensors.

+    Parameters: dData - dictionary object containing data items to be

+                        written to the rr database file

+    Returns: True if successful, False otherwise

+    """

+ 

+    epochTime = getEpochSeconds(dData['time'])

+

+    # Format the rrdtool update command.

+    strFmt = "rrdtool update %s %s:%s:%s:%s:%s:%s"

+    strCmd = strFmt % (_RRD_FILE, epochTime, dData['current'], \

+             dData['voltage'], dData['power'], dData['battemp'], \

+             dData['ambtemp'])

+

+    if debugMode:

+        print("%s" % strCmd) # DEBUG

+

+    # Run the command as a subprocess.

+    try:

+        subprocess.check_output(strCmd, shell=True, \

+            stderr=subprocess.STDOUT)

+    except subprocess.CalledProcessError as exError:

+        print("%s: rrdtool update failed: %s" % \

+            (getTimeStamp(), exError.output))

+        return False

+

+    if verboseMode and not debugMode:

+        print("database updated")

+

+    return True

+## end def

+

 def createGraph(fileName, dataItem, gLabel, gTitle, gStart,

                 lower=0, upper=0, trendLine=0, scaleFactor=1,

                 autoScale=True, alertLine=""):

@@ -314,8 +312,8 @@ def createGraph(fileName, dataItem, gLabel, gTitle, gStart,

     if alertLine != "":

         strCmd += "HRULE:%s#FF0000:Critical\ Low\ Voltage " % (alertLine)

-    if verboseDebug:

-        print("%s" % strCmd) # DEBUG

+    if debugMode:

+        print("%s\n" % strCmd) # DEBUG

     # Run the formatted rrdtool command as a subprocess.

     try:

@@ -326,7 +324,7 @@ def createGraph(fileName, dataItem, gLabel, gTitle, gStart,

         print("rrdtool graph failed: %s" % (exError.output))

         return False

-    if debugOption:

+    if verboseMode and not debugMode:

         print("rrdtool graph: %s" % result.decode('utf-8'))

     return True

@@ -398,20 +396,20 @@ def getCLarguments():

     """

     Get command line arguments.  There are three possible arguments

         -d turns on debug mode

-        -v turns on verbose debug mode

+        -v turns on verbose mode

         -p sets the sensor query period

         -c sets the chart update period

     Returns: nothing

     """

-    global debugOption, verboseDebug, dataRequestInterval, chartUpdateInterval

+    global debugMode, verboseMode, dataRequestInterval, chartUpdateInterval

     index = 1

     while index < len(sys.argv):

-        if sys.argv[index] == '-d':

-            debugOption = True

-        elif sys.argv[index] == '-v':

-            debugOption = True

-            verboseDebug = True

+        if sys.argv[index] == '-v':

+            verboseMode = True

+        elif sys.argv[index] == '-d':

+            debugMode = True

+            verboseMode = True

         elif sys.argv[index] == '-p':

             try:

                 dataRequestInterval = abs(int(sys.argv[index + 1]))

@@ -475,7 +473,6 @@ def main():

         if currentTime - lastDataRequestTime > dataRequestInterval:

             lastDataRequestTime = currentTime

             dData = {}

-            result = True

             # Get the data from the sensors.

             result =getSensorData(dData)

@@ -501,7 +498,7 @@ def main():

         # the next update interval.

         elapsedTime = time.time() - currentTime

-        if debugOption:

+        if verboseMode:

             if result:

                 print("update successful: %6f sec\n"

                       % elapsedTime)

@@ -39,11 +39,15 @@ import signal

 import subprocess

 import multiprocessing

 import time

+import json

 # Import sensor libraries.

 import ina260 # power sensor

 import tmp102 # temperature sensor

+    ### ENVIRONMENT ###

+_USER = os.environ['USER']

+

     ### SENSOR BUS ADDRESSES ###

 # Set bus addresses of sensors.

@@ -55,8 +59,7 @@ _BUS_SEL = 1

     ### FILE AND FOLDER LOCATIONS ###

-_USER = os.environ['USER']

-# folder to contain dynamic data objects

+# folder to contain html

 _DOCROOT_PATH = "/home/%s/public_html/power/" % _USER

 # folder to contain charts and output data file

 _CHARTS_DIRECTORY = _DOCROOT_PATH + "dynamic/"

@@ -67,10 +70,10 @@ _RRD_FILE = "/home/%s/database/powerData.rrd" % _USER

     ### GLOBAL CONSTANTS ###

-# rrdtool database update interval in seconds

-_DATABASE_UPDATE_INTERVAL = 30

 # sensor data request interval in seconds

 _DEFAULT_DATA_REQUEST_INTERVAL = 2

+# rrdtool database update interval in seconds

+_DATABASE_UPDATE_INTERVAL = 30

 # chart update interval in seconds

 _CHART_UPDATE_INTERVAL = 600

 # standard chart width in pixels

@@ -85,6 +88,7 @@ _AVERAGE_LINE_COLOR = '#006600'

 # debug output options

 debugOption = False

 verboseDebug = False

+

 # frequency of data requests to sensors

 dataRequestInterval = _DEFAULT_DATA_REQUEST_INTERVAL

 # how often charts get updated

@@ -101,7 +105,7 @@ atmp = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_SEL)

 def getTimeStamp():

     """

-    Set the error message time stamp to the local system time.

+    Get the local time and format as a text string.

     Parameters: none

     Returns: string containing the time stamp

     """

@@ -109,57 +113,58 @@ def getTimeStamp():

 ## end def

 def getEpochSeconds(sTime):

-    """Convert the time stamp supplied in the weather data string

-       to seconds since 1/1/1970 00:00:00.

-       Parameters: 

-           sTime - the time stamp to be converted must be formatted

+    """

+    Convert the time stamp to seconds since 1/1/1970 00:00:00.

+    Parameters: 

+        sTime - the time stamp to be converted must be formatted

                    as %m/%d/%Y %H:%M:%S

-       Returns: epoch seconds

+    Returns: epoch seconds

     """

     try:

         t_sTime = time.strptime(sTime, '%m/%d/%Y %H:%M:%S')

-    except Exception, exError:

-        print '%s getEpochSeconds: %s' % (getTimeStamp(), exError)

+    except Exception as exError:

+        print('%s getEpochSeconds: %s' % (getTimeStamp(), exError))

         return None

     tSeconds = int(time.mktime(t_sTime))

     return tSeconds

 ## end def

 def terminateAgentProcess(signal, frame):

-    """Send a message to the log when the agent process gets killed

-       by the operating system.  Inform downstream clients

-       by removing output data files.

-       Parameters:

-           signal, frame - dummy parameters

-       Returns: nothing

+    """

+    Send a message to the log when the agent process gets killed

+    by the operating system.  Inform downstream clients

+    by removing output data files.

+    Parameters:

+        signal, frame - dummy parameters

+    Returns: nothing

     """

     # Inform downstream clients by removing output data file.

     if os.path.exists(_OUTPUT_DATA_FILE):

        os.remove(_OUTPUT_DATA_FILE)

-    print '%s terminating npw agent process' % \

-              (getTimeStamp())

+    print('%s terminating npw agent process' % getTimeStamp())

     sys.exit(0)

 ## end def

   ###  PUBLIC METHODS  ###

 def getSensorData(dData):

-    """Poll sensors for data. Store the data in a dictionary object for

-       use by other subroutines.  The dictionary object passed in should

-       an empty dictionary, i.e., dData = { }.

-       Parameters: dData - a dictionary object to contain the sensor data

-       Returns: True if successful, False otherwise

     """

+    Poll sensors for data. Store the data in a dictionary object for

+    use by other subroutines.  The dictionary object passed in should

+    an empty dictionary, i.e., dData = { }.

+    Parameters: dData - a dictionary object to contain the sensor data

+    Returns: True if successful, False otherwise

+    """

+    dData["time"] = getTimeStamp()

+ 

     try:

-        dData["time"] = getTimeStamp()

         dData["current"] = pwr.getCurrent()

         dData["voltage"] = pwr.getVoltage()

         dData["power"] = pwr.getPower()