@@ -5,13 +5,11 @@

 # whether your local network uses a domain name server.

 #

-APP_PATH="/home/$USER/bin"

-LOG_PATH="/home/$USER/log"

-

 AGENT_NAME="[a]rednsigAgent.py"

+SOURCE_URL="http://localnode.local.mesh/cgi-bin/status"

-#NODE_URL="http://localnode:8080/cgi-bin/signal.json"

-NODE_URL="http://192.168.1.30:8080/cgi-bin/status"

+APP_PATH="/home/$USER/bin"

+LOG_PATH="/home/$USER/log"

 # Changing the value overides the default data request interval hardcoded

 # in the agent script.  '60' is the default. Value is in seconds.

@@ -26,7 +24,11 @@ if [ -n "$PROCESS_ID" ]; then

 else

   printf "starting up arednsig agent\n"

   cd $APP_PATH

-  $(./$AGENT_NAME -u $NODE_URL -p $POLLING_INTERVAL >> \

- $LOG_PATH/arednsigAgent.log 2>&1 &)

+  if [ "$1" != "" ]; then

+    ./$AGENT_NAME $1 -u $SOURCE_URL -p $POLLING_INTERVAL

+  else

+    ./$AGENT_NAME -u $SOURCE_URL -p $POLLING_INTERVAL >> \

+      $LOG_PATH/arednsigAgent.log 2>&1 &

+  fi

 fi

@@ -1,5 +1,5 @@

 #!/bin/bash

-# Stop the radmon agent process and clean up environment.

+# Stop the arednsig agent process.

 AGENT_NAME="[a]rednsigAgent.py"

@@ -1,4 +1,4 @@

-#!/usr/bin/python2 -u

+#!/usr/bin/python3 -u

 # The -u option above turns off block buffering of python output. This 

 # assures that each error message gets individually printed to the log file.

 #

@@ -36,24 +36,30 @@

 #   * v22 released 31 Mar 2020 by J L Owrey; upgraded for compatibility with

 #     Aredn firmware version 3.20.3.0.  This agent now downloads the node's

 #     status page and parsed the signal data from the html.

+#   * v23 released 11 Jun 2021 by J L Owrey; remove unused code.

+#   * v24 released 14 Jun 2021 by J L Owrey; minor revisions

 #

 #2345678901234567890123456789012345678901234567890123456789012345678901234567890

 import os

-import urllib2

 import sys

 import signal

 import subprocess

 import multiprocessing

 import time

+import json

+from urllib.request import urlopen

+

+   ### ENVIRONMENT ###

 _USER = os.environ['USER']

+_SERVER_MODE = "primary"

    ### DEFAULT AREDN NODE URL ###

 # set url of the aredn node

-_DEFAULT_AREDN_NODE_URL = "http://localnode:8080/cgi-bin/status"

+_DEFAULT_AREDN_NODE_URL = "http://localnode.local.mesh/cgi-bin/status"

     ### FILE AND FOLDER LOCATIONS ###

@@ -62,30 +68,26 @@ _DOCROOT_PATH = "/home/%s/public_html/arednsig/" % _USER

 # folder for charts and output data file

 _CHARTS_DIRECTORY = _DOCROOT_PATH + "dynamic/"

 # location of data output file

-_OUTPUT_DATA_FILE = _DOCROOT_PATH + "dynamic/arednsigOutputData.js"

-# dummy output data file

-_DUMMY_OUTPUT_FILE = _DOCROOT_PATH + "dynamic/nodeOnline.js"

+_OUTPUT_DATA_FILE = _DOCROOT_PATH + "dynamic/arednsigData.js"

 # database that stores node data

 _RRD_FILE = "/home/%s/database/arednsigData.rrd" % _USER

     ### GLOBAL CONSTANTS ###

+# max number of failed data requests allowed

+_MAX_FAILED_DATA_REQUESTS = 2

 # AREDN node data request interval in seconds

 _DEFAULT_DATA_REQUEST_INTERVAL = 60

+# number seconds to wait for a response to HTTP request

+_HTTP_REQUEST_TIMEOUT = 5

+

 # chart update interval in seconds

 _CHART_UPDATE_INTERVAL = 600

-

-# number seconds to wait for a response to HTTP request

-_HTTP_REQUEST_TIMEOUT = 10

-# max number of failed data requests allowed

-_MAX_FAILED_DATA_REQUESTS = 0

 # standard chart width in pixels

 _CHART_WIDTH = 600

 # standard chart height in pixels

 _CHART_HEIGHT = 150

 # Set this to True only if this server is intended to relay raw

-# node data to a mirror server.

-_RELAY_SERVER = False

    ### GLOBAL VARIABLES ###

@@ -107,8 +109,6 @@ arednNodeUrl = _DEFAULT_AREDN_NODE_URL

 dataRequestInterval = _DEFAULT_DATA_REQUEST_INTERVAL

 # chart update interval

 chartUpdateInterval = _CHART_UPDATE_INTERVAL

-# last node request time

-lastDataPointTime = -1

   ###  PRIVATE METHODS  ###

@@ -122,7 +122,7 @@ def getTimeStamp():

 ##end def

 def getEpochSeconds(sTime):

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

+    """Convert the time stamp supplied in the supplied string

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

        Parameters: 

            sTime - the time stamp to be converted must be formatted

@@ -131,8 +131,8 @@ def getEpochSeconds(sTime):

     """

     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

@@ -150,12 +150,10 @@ def setStatusToOffline():

     # Inform downstream clients by removing output data file.

     if os.path.exists(_OUTPUT_DATA_FILE):

        os.remove(_OUTPUT_DATA_FILE)

-    if os.path.exists(_DUMMY_OUTPUT_FILE):

-       os.remove(_DUMMY_OUTPUT_FILE)

     # If the aredn node was previously online, then send

     # a message that we are now offline.

     if nodeOnline:

-        print '%s aredn node offline' % getTimeStamp()

+        print('%s aredn node offline' % getTimeStamp())

     nodeOnline = False

 ##end def

@@ -170,16 +168,13 @@ def terminateAgentProcess(signal, frame):

     # Inform downstream clients by removing output data file.

     if os.path.exists(_OUTPUT_DATA_FILE):

        os.remove(_OUTPUT_DATA_FILE)

-    if os.path.exists(_DUMMY_OUTPUT_FILE):

-       os.remove(_DUMMY_OUTPUT_FILE)

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

-              (getTimeStamp())

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

     sys.exit(0)

 ##end def

   ###  PUBLIC METHODS  ###

-def getArednNodeData():

+def getNodeData():

     """Send http request to aredn node.  The response from the

        node contains the node signal data as unformatted ascii text.

        Parameters: none

@@ -187,44 +182,51 @@ def getArednNodeData():

                 or None if not successful

     """

     try:

-        conn = urllib2.urlopen(arednNodeUrl, timeout=_HTTP_REQUEST_TIMEOUT)

+        currentTime = time.time()

-        # Format received data into a single string.

-        content = ""

-        for line in conn:

-            content += line.strip()

-        del conn

+        response = urlopen(arednNodeUrl, timeout=_HTTP_REQUEST_TIMEOUT)

-    except Exception, exError:

+        if debugOption:

+            requestTime = time.time() - currentTime

+            print("http request: %.4f seconds" % requestTime)

+

+        content = response.read().decode('utf-8')

+        content = content.replace('\n', '')

+        content = content.replace('\r', '')

+        if content == "":

+            raise Exception("empty response")

+        

+    except Exception as exError:

         # If no response is received from the device, then assume that

         # the device is down or unavailable over the network.  In

         # that case return None to the calling function.

-        print "%s http error: %s" % (getTimeStamp(), exError)

+        print("%s getNodeData: %s" % (getTimeStamp(), exError))

         return None

+    ##end try

     if verboseDebug:

-        print "http request successful: %d bytes" % len(content)

-

+        print(content)

+   

     return content

 ##end def

-def parseNodeData(sData, dData):

-    """Parse the node  signal data JSON string from the aredn node

+def parseDataString(sData, dData):

+    """Parse the node signal data JSON string from the aredn node

        into its component parts.  

        Parameters:

            sData - the string containing the data to be parsed

            dData - a dictionary object to contain the parsed data items

        Returns: True if successful, False otherwise

     """

-    

-

+ 

     try:

         strBeginSearch = '<nobr>Signal/Noise/Ratio</nobr></th>' \

                          '<td valign=middle><nobr><big><b>'

-        strEndSearch = 'dB'

+        strEndSearch = 'dB</b>'

         iBeginIndex = sData.find(strBeginSearch) + len(strBeginSearch)

         iEndIndex = sData.find(strEndSearch, iBeginIndex)

+        #print("search params: %d, %d" % (iBeginIndex, iEndIndex))

         if iBeginIndex == -1 or iEndIndex == -1:

             raise Exception("signal data not found in status page")

@@ -234,17 +236,14 @@ def parseNodeData(sData, dData):

         lsnr = snr.split('/')

         dData['time'] = getEpochSeconds(getTimeStamp())

-

         dData['signal'] = lsnr[0]

         dData['noise'] = lsnr[1]

         dData['snr'] = lsnr[2]

-    except Exception, exError:

-        print "%s parse failed: %s" % (getTimeStamp(), exError)

+    except Exception as exError:

+        print("%s parse failed: %s" % (getTimeStamp(), exError))

         return False

-    if verboseDebug:

-        print "parse successful"

     return True

 ##end def

@@ -264,21 +263,24 @@ def updateDatabase(dData):

              '0', '0', '0')

     if verboseDebug:

-        print "%s" % strCmd # DEBUG

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

     # Run the command as a subprocess.

     try:

         subprocess.check_output(strCmd, shell=True,  \

                              stderr=subprocess.STDOUT)

-    except subprocess.CalledProcessError, exError:

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

-                    (getTimeStamp(), exError.output)

+    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 writeOutputDataFile(sData, dData):

+def writeOutputFile(dData):

     """Write node data items to the output data file, formatted as 

        a Javascript file.  This file may then be accessed and used by

        by downstream clients, for instance, in HTML documents.

@@ -293,28 +295,29 @@ def writeOutputDataFile(sData, dData):

     #    * The data request interval

     lastUpdate = time.strftime( "%m.%d.%Y %T", 

                                 time.localtime(dData['time']) )

-    sDate = "[{\"date\":\"%s\",\"period\":\"%s\"}]" % \

-           (lastUpdate, chartUpdateInterval)

+

+    # Format data into a JSON string.

     try:

-        fc = open(_DUMMY_OUTPUT_FILE, "w")

-        fc.write(sDate)

-        fc.close()

-    except Exception, exError:

-        print "%s write node file failed: %s" % (getTimeStamp(), exError)

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

+        jsData.update({"date": lastUpdate})

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

+        jsData.update({"dataRequestInterval": dataRequestInterval})

+        jsData.update({"serverMode": _SERVER_MODE})

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

+    except Exception as exError:

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

         return False

-    if _RELAY_SERVER:

-        # Write the entire node data response to the output data file.

-        try:

-            fc = open(_OUTPUT_DATA_FILE, "w")

-            fc.write(sData)

-            fc.close()

-        except Exception, exError:

-            print "%s write output file failed: %s" % \

-                  (getTimeStamp(), exError)

-            return False

-        if verboseDebug:

-            print "write output data file: %d bytes" % len(sData)

+    if verboseDebug:

+        print(sData)

+

+    try:

+        fc = open(_OUTPUT_DATA_FILE, "w")

+        fc.write(sData)

+        fc.close()

+    except Exception as exError:

+        print("%s write output file failed: %s" % (getTimeStamp(), exError))

+        return False

     return True

 ## end def

@@ -335,7 +338,7 @@ def setNodeStatus(updateSuccess):

         # Set status and send a message to the log if the node was

         # previously offline and is now online.

         if not nodeOnline:

-            print '%s aredn node online' % getTimeStamp()

+            print('%s aredn node online' % getTimeStamp())

             nodeOnline = True

     else:

         # The last attempt failed, so update the failed attempts

@@ -394,27 +397,27 @@ def createGraph(fileName, dataItem, gLabel, gTitle, gStart,

     if addTrend == 0:

         strCmd += "LINE1:dSeries#0400ff "

     elif addTrend == 1:

-        strCmd += "CDEF:smoothed=dSeries,%s,TREND LINE3:smoothed#ff0000 " \

+        strCmd += "CDEF:smoothed=dSeries,%s,TREND LINE2:smoothed#006600 " \

                   % trendWindow[gStart]

     elif addTrend == 2:

         strCmd += "LINE1:dSeries#0400ff "

-        strCmd += "CDEF:smoothed=dSeries,%s,TREND LINE3:smoothed#ff0000 " \

+        strCmd += "CDEF:smoothed=dSeries,%s,TREND LINE2:smoothed#006600 " \

                   % trendWindow[gStart]

     if verboseDebug:

-        print "%s" % strCmd # DEBUG

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

     # Run the formatted rrdtool command as a subprocess.

     try:

         result = subprocess.check_output(strCmd, \

                      stderr=subprocess.STDOUT,   \

                      shell=True)

-    except subprocess.CalledProcessError, exError:

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

+    except subprocess.CalledProcessError as exError:

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

         return False

     if debugOption:

-        print "rrdtool graph: %s\n" % result,

+        print("rrdtool graph: %s\n" % result.decode('utf-8'), end='')

     return True

 ##end def

@@ -456,7 +459,7 @@ def generateGraphs():

                 'SNR\ -\ Past\ Year', 'end-12months', 0, 0, 2, autoScale)

     if debugOption:

-        #print # print a blank line to improve readability when in debug mode

+        #print() # print a blank line to improve readability when in debug mode

         pass

 ##end def

@@ -482,15 +485,17 @@ def getCLarguments():

             try:

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

             except:

-                print "invalid polling period"

+                print("invalid polling period")

                 exit(-1)

             index += 1

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

             arednNodeUrl = sys.argv[index + 1]

+            if arednNodeUrl.find('http://') < 0:

+                arednNodeUrl = 'http://' + arednNodeUrl

             index += 1

         else:

             cmd_name = sys.argv[0].split('/')

-            print "Usage: %s [-d] [-v] [-p seconds] [-u url]" % cmd_name[-1]

+            print("Usage: %s [-d] [-v] [-p seconds] [-u url]" % cmd_name[-1])

             exit(-1)

         index += 1

 ##end def

@@ -504,9 +509,10 @@ def main():

     global dataRequestInterval

     signal.signal(signal.SIGTERM, terminateAgentProcess)

+    signal.signal(signal.SIGINT, terminateAgentProcess)

-    print '%s starting up arednsig agent process' % \

-                  (getTimeStamp())

+    print('%s starting up arednsig agent process' % \

+                  (getTimeStamp()))

     # last time output JSON file updated

     lastDataRequestTime = -1

@@ -520,9 +526,9 @@ def main():

     ## Exit with error if rrdtool database does not exist.

     if not os.path.exists(_RRD_FILE):

-        print 'rrdtool database does not exist\n' \

+        print('rrdtool database does not exist\n' \

               'use createArednsigRrd script to ' \

-              'create rrdtool database\n'

+              'create rrdtool database\n')

         exit(1)

     ## main loop

@@ -538,21 +544,23 @@ def main():

             result = True

             # Get the data string from the device.

-            sData = getArednNodeData()

+            sData = getNodeData()

+

             # If the first http request fails, try one more time.

             if sData == None:

                 result = False

-

+            

             # If successful parse the data.

             if result:

-                result = parseNodeData(sData, dData)

-           

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

+                result = parseDataString(sData, dData)

+

+            # If parse successful, write data output data file.

             if result:

-                result = updateDatabase(dData)

+                writeOutputFile(dData)

+            # If write output file successful, update the database.

             if result:

-                writeOutputDataFile(sData, dData)

+                result = updateDatabase(dData)

             # Set the node status to online or offline depending on the

             # success or failure of the above operations.

@@ -571,10 +579,10 @@ def main():

         elapsedTime = time.time() - currentTime

         if debugOption:

             if result:

-                print "%s update successful:" % getTimeStamp(),

+                print("%s update successful:" % getTimeStamp(), end='')

             else:

-                print "%s update failed:" % getTimeStamp(),

-            print "%6f seconds processing time\n" % elapsedTime 

+                print("%s update failed:" % getTimeStamp(), end='')

+            print(" %6f seconds\n" % elapsedTime)

         remainingTime = dataRequestInterval - elapsedTime

         if remainingTime > 0.0:

             time.sleep(remainingTime)

@@ -583,8 +591,5 @@ def main():

 ## end def

 if __name__ == '__main__':

-    try:

-        main()

-    except KeyboardInterrupt:

-        print '\n',

-        terminateAgentProcess('KeyboardInterrupt','Module')

+    main()

+