#!/usr/bin/python2 -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. # # Module: nodepowerAgent.py # # Description: This module acts as an agent between the mesh network and # node power and enviromental sensors. The agent periodically polls the # sensors and processes the data returned from the sensors, including # - conversion of data items # - update a round robin (rrdtool) database with the sensor data # - periodically generate graphic charts for display in html documents # - write the processed node status to a JSON file for use by html # documents # # Copyright 2021 Jeff Owrey # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see http://www.gnu.org/license. # # Revision History # * v10 released 01 June 2021 by J L Owrey; first release # #2345678901234567890123456789012345678901234567890123456789012345678901234567890 # Import required python libraries. import os import sys import signal import subprocess import multiprocessing import time # Import sensor libraries. import ina260 # power sensor import tmp102 # temperature sensor ### SENSOR BUS ADDRESSES ### # Set bus addresses of sensors _PWR_SENSOR_ADDR = 0X40 _BAT_TMP_SENSOR_ADDR = 0x48 _AMB_TMP_SENSOR_ADDR = 0x4B # Set bus selector _BUS_SEL = 1 ### FILE AND FOLDER LOCATIONS ### _USER = os.environ['USER'] # folder for containing dynamic data objects _DOCROOT_PATH = "/home/%s/public_html/power/" % _USER # folder for charts and output data file _CHARTS_DIRECTORY = _DOCROOT_PATH + "dynamic/" # location of data output file _OUTPUT_DATA_FILE = _DOCROOT_PATH + "dynamic/powerData.js" # database that stores node data _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 # chart update interval in seconds _CHART_UPDATE_INTERVAL = 600 # standard chart width in pixels _CHART_WIDTH = 600 # standard chart height in pixels _CHART_HEIGHT = 150 ### GLOBAL VARIABLES ### # turn on or off of verbose debugging information debugOption = False verboseDebug = False # frequency of data requests to sensors dataRequestInterval = _DEFAULT_DATA_REQUEST_INTERVAL # chart update interval 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) btmp = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_SEL) atmp = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_SEL) ### PRIVATE METHODS ### def getTimeStamp(): """ Set the error message time stamp to the local system time. Parameters: none Returns: string containing the time stamp """ return time.strftime( "%m/%d/%Y %T", time.localtime() ) ##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 as %m/%d/%Y %H:%M:%S Returns: epoch seconds """ try: t_sTime = time.strptime(sTime, '%m/%d/%Y %H:%M:%S') except Exception, 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 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 """ # 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()) sys.exit(0) ##end def ### PUBLIC METHODS ### def getSensorData(dData): """Poll sensors for data. Parameters: none Returns: a string containing the node signal data if successful, or None if not successful """ try: dData["time"] = getTimeStamp() dData["current"] = pwr.getCurrent() dData["voltage"] = pwr.getVoltage() dData["power"] = pwr.getPower() dData["battemp"] = btmp.getTempC() dData["ambtemp"] = atmp.getTempC() except Exception, exError: print "%s sensor error: %s" % (getTimeStamp(), exError) return False 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 debugOption: 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) return False return True ##end def def writeOutputDataFile(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. Parameters: sData - a string object containing the data to be written to the output data file Returns: True if successful, False otherwise """ # Write a JSON formatted file for use by html clients. The following # data items are sent to the client file. # * The last database update date and time # * The data request interval # * The sensor values # Create a JSON formatted string from the sensor data. sData = "[{\"period\":\"%s\", " % \ (chartUpdateInterval) for key in dData: sData += '\"%s\":\"%s\", ' % (key, dData[key]) sData = sData[:-2] + '}]\n' # Write the JSON formatted data 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 sData[:-1] if debugOption: print "writing output data file: %d bytes" % len(sData) return True ## end def def createGraph(fileName, dataItem, gLabel, gTitle, gStart, lower, upper, addTrend, autoScale): """Uses rrdtool to create a graph of specified node data item. Parameters: fileName - name of file containing the graph dataItem - data item to be graphed gLabel - string containing a graph label for the data item gTitle - string containing a title for the graph gStart - beginning time of the graphed data lower - lower bound for graph ordinate #NOT USED upper - upper bound for graph ordinate #NOT USED addTrend - 0, show only graph data 1, show only a trend line 2, show a trend line and the graph data autoScale - if True, then use vertical axis auto scaling (lower and upper parameters are ignored), otherwise use lower and upper parameters to set vertical axis scale Returns: True if successful, False otherwise """ gPath = _CHARTS_DIRECTORY + fileName + ".png" trendWindow = { 'end-1day': 7200, 'end-4weeks': 172800, 'end-12months': 604800 } # Format the rrdtool graph command. # Set chart start time, height, and width. strCmd = "rrdtool graph %s -a PNG -s %s -e now -w %s -h %s " \ % (gPath, gStart, _CHART_WIDTH, _CHART_HEIGHT) # Set the range and scaling of the chart y-axis. if lower < upper: strCmd += "-l %s -u %s -r " % (lower, upper) elif autoScale: strCmd += "-A " strCmd += "-Y " # Set the chart ordinate label and chart title. strCmd += "-v %s -t %s " % (gLabel, gTitle) # Show the data, or a moving average trend line over # the data, or both. strCmd += "DEF:dSeries=%s:%s:LAST " % (_RRD_FILE, dataItem) if addTrend == 0: strCmd += "LINE1:dSeries#0400ff " elif addTrend == 1: strCmd += "CDEF:smoothed=dSeries,%s,TREND LINE3:smoothed#ff0000 " \ % trendWindow[gStart] elif addTrend == 2: strCmd += "LINE1:dSeries#0400ff " strCmd += "CDEF:smoothed=dSeries,%s,TREND LINE3:smoothed#ff0000 " \ % trendWindow[gStart] if verboseDebug: 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) return False if debugOption: print "rrdtool graph: %s\n" % result, return True ##end def def generateGraphs(): """Generate graphs for display in html documents. Parameters: none Returns: nothing """ autoScale = False # 24 hour stock charts createGraph('24hr_current', 'CUR', 'mA', 'Current\ -\ Last\ 24\ Hours', 'end-1day', 0, 0, 2, autoScale) createGraph('24hr_voltage', 'VOLT', 'V', 'Voltage\ -\ Last\ 24\ Hours', 'end-1day', 0, 0, 2, autoScale) createGraph('24hr_power', 'PWR', 'mW', 'Power\ -\ Last\ 24\ Hours', 'end-1day', 0, 0, 2, autoScale) createGraph('24hr_battemp', 'BTMP', 'deg\ C', 'Battery\ Temperature\ -\ Last\ 24\ Hours', 'end-1day', \ 0, 0, 2, autoScale) createGraph('24hr_ambtemp', 'ATMP', 'deg\ C', 'Ambient\ Temperature\ -\ Last\ 24\ Hours', 'end-1day', \ 0, 0, 2, autoScale) # 4 week stock charts createGraph('4wk_current', 'CUR', 'mA', 'Current\ -\ Last\ 4\ Weeks', 'end-4weeks', 0, 0, 2, autoScale) createGraph('4wk_voltage', 'VOLT', 'V', 'Voltage\ -\ Last\ 4\ Weeks', 'end-4weeks', 0, 0, 2, autoScale) createGraph('4wk_power', 'PWR', 'mW', 'Power\ -\ Last\ 4\ Weeks', 'end-4weeks', 0, 0, 2, autoScale) createGraph('4wk_battemp', 'BTMP', 'deg\ C', 'Battery\ Temperature\ -\ Last\ 4\ Weeks', 'end-4weeks', \ 0, 0, 2, autoScale) createGraph('4wk_ambtemp', 'ATMP', 'deg\ C', 'Ambient\ Temperature\ -\ Last\ 4\ Weeks', 'end-4weeks', \ 0, 0, 2, autoScale) # 12 month stock charts createGraph('12m_current', 'CUR', 'mA', 'Current\ -\ Past\ Year', 'end-12months', 0, 0, 2, autoScale) createGraph('12m_voltage', 'VOLT', 'V', 'Voltage\ -\ Past\ Year', 'end-12months', 0, 0, 2, autoScale) createGraph('12m_power', 'PWR', 'mW', 'Power\ -\ Past\ Year', 'end-12months', 0, 0, 2, autoScale) createGraph('12m_battemp', 'BTMP', 'deg\ C', 'Battery\ Temperature\ -\ Past\ Year', 'end-12months', \ 0, 0, 2, autoScale) createGraph('12m_ambtemp', 'ATMP', 'deg\ C', 'Ambient\ Temperature\ -\ Past\ Year', 'end-12months', \ 0, 0, 2, autoScale) ##end def def getCLarguments(): """Get command line arguments. There are three possible arguments -d turns on debug mode -v turns on verbose debug mode -t sets the sensor query interval Returns: nothing """ global debugOption, verboseDebug, dataRequestInterval index = 1 while index < len(sys.argv): if sys.argv[index] == '-d': debugOption = True elif sys.argv[index] == '-v': debugOption = True verboseDebug = True elif sys.argv[index] == '-p': try: dataRequestInterval = abs(int(sys.argv[index + 1])) except: print "invalid polling period" exit(-1) index += 1 else: cmd_name = sys.argv[0].split('/') print "Usage: %s [-d] [-v] [-p seconds]" % cmd_name[-1] exit(-1) index += 1 ##end def def main(): """Handles timing of events and acts as executive routine managing all other functions. Parameters: none Returns: nothing """ global dataRequestInterval signal.signal(signal.SIGTERM, terminateAgentProcess) print '%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() ## Exit with error if rrdtool database does not exist. if not os.path.exists(_RRD_FILE): print 'rrdtool database does not exist\n' \ 'use createArednsigRrd script to ' \ 'create rrdtool database\n' exit(1) ## main loop while True: currentTime = time.time() # get current time in seconds # Every web update interval request data from the aredn # node and process the received data. if currentTime - lastDataRequestTime > dataRequestInterval: lastDataRequestTime = currentTime dData = {} result = True # Get the data from the sensors. result =getSensorData(dData) # If get data successful, write data to data files. if result: result = writeOutputDataFile(dData) # At the rrdtool database update interval, update the database. if currentTime - lastDatabaseUpdateTime > \ _DATABASE_UPDATE_INTERVAL: lastDatabaseUpdateTime = currentTime ## Update the round robin database with the parsed data. if result: updateDatabase(dData) # At the chart generation interval, generate charts. if currentTime - lastChartUpdateTime > chartUpdateInterval: lastChartUpdateTime = currentTime p = multiprocessing.Process(target=generateGraphs, args=()) p.start() # Relinquish processing back to the operating system until # the next update interval. elapsedTime = time.time() - currentTime if debugOption: if result: print "%s update successful:" % getTimeStamp(), else: print "%s update failed:" % getTimeStamp(), print "%6f seconds processing time\n" % elapsedTime remainingTime = dataRequestInterval - elapsedTime if remainingTime > 0.0: time.sleep(remainingTime) ## end while return ## end def if __name__ == '__main__': try: main() except KeyboardInterrupt: print '\n', terminateAgentProcess('KeyboardInterrupt','Module')