@@ -7,7 +7,7 @@

 # Description: Creates a rrdtool database for use by the power agent to

 # store the data from the power and temperature sensors.  The agent uses

 # the data in the database to generate graphic charts for display in the

-# weather station web page.

+# node power web page.

 #

 # Copyright 2021 Jeff Owrey

 #    This program is free software: you can redistribute it and/or modify

new file mode 100755

@@ -0,0 +1,93 @@

+#!/usr/bin/python -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: createPowerRrd.py

+#

+# Description: Creates a rrdtool database for use by the power agent to

+# store the data from the power and temperature sensors.  The agent uses

+# the data in the database to generate graphic charts for display in the

+# weather station web page.

+#

+# 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 Jun 2021 by J L Owrey

+#

+#2345678901234567890123456789012345678901234567890123456789012345678901234567890

+

+import os

+import time

+import subprocess

+

+    ### DEFINE DATABASE FILE LOCATION ###

+

+_USER = os.environ['USER']

+# the file that stores the data

+_RRD_FILE = "/home/%s/database/powerData.rrd" % _USER

+

+   ### DEFINE DATABASE SIZE AND GRANULARITY

+

+_RRD_SIZE_IN_DAYS = 740 # days

+_1YR_RRA_STEPS_PER_DAY = 1440

+_DATABASE_UPDATE_INTERVAL = 30

+

+def createRrdFile():

+    """Create the rrd file if it does not exist.

+       Parameters: none

+       Returns: True, if successful

+    """

+

+    if os.path.exists(_RRD_FILE):

+        print "power database already exists"

+        return True

+

+     ## Calculate database size

+ 

+    heartBeat = 2 * _DATABASE_UPDATE_INTERVAL

+    rra1yrNumPDP =  int(round(86400 / (_1YR_RRA_STEPS_PER_DAY * \

+                    _DATABASE_UPDATE_INTERVAL)))

+    rrd24hrNumRows = int(round(86400 / _DATABASE_UPDATE_INTERVAL))

+    rrd1yearNumRows = _1YR_RRA_STEPS_PER_DAY * _RRD_SIZE_IN_DAYS

+       

+    strFmt = ("rrdtool create %s --start now-1day --step %s "

+              "DS:CUR:GAUGE:%s:U:U DS:VOLT:GAUGE:%s:U:U "

+              "DS:PWR:GAUGE:%s:U:U DS:BTMP:GAUGE:%s:U:U "

+              "DS:ATMP:GAUGE:%s:U:U "

+              "RRA:LAST:0.5:1:%s RRA:LAST:0.5:%s:%s")

+

+    strCmd = strFmt % (_RRD_FILE, _DATABASE_UPDATE_INTERVAL,           \

+                heartBeat, heartBeat, heartBeat, heartBeat, heartBeat, \

+                rrd24hrNumRows, rra1yrNumPDP, rrd1yearNumRows)

+

+    print "creating power database...\n\n%s\n" % strCmd

+

+    # Spawn a sub-shell and run the command

+    try:

+        subprocess.check_output(strCmd, stderr=subprocess.STDOUT, \

+                                shell=True)

+    except subprocess.CalledProcessError, exError:

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

+        return False

+    return True

+##end def

+

+def main():

+    createRrdFile()

+## end def

+

+if __name__ == '__main__':

+    main()

+