#!/usr/bin/perl
# This script generates the trend graphs for the pressure reading. It takes
# parameters "unit" (naming the unit) and "length" with values 0...4,
# for day/week/month/quarter/year as arguments, passed by via GET method.
# Directories where the log files reside in
#$logdir="/home/chris/BTUmetering/log";
#$gnudir="/home/chris/BTUmetering/gnuplot";
$logdir="MAINPROGROOT/log";
$gnudir="MAINPROGROOT/gnuplot";
# Image directory:
# $imgdir="/srv/www/htdocs/img2";
$imgdir="HTDOCROOT/img2";
@allowedcores = ("AHU2");
# Following http://www.tutorialspoint.com/perl/perl_cgi.htm, we extract the
# parameters sent via get:
local ($buffer, @pairs, $pair, $name, $value, %FORM);
# Read in text
$ENV{'REQUEST_METHOD'} =~ tr/a-z/A-Z/;
if ($ENV{'REQUEST_METHOD'} eq "GET")
{
$buffer = $ENV{'QUERY_STRING'};
}
# sanitize input
$buffer =~ s/[^\w =&+]//g;
# Split information into name/value pairs
@pairs = split(/&/, $buffer);
foreach $pair (@pairs)
{
($name, $value) = split(/=/, $pair);
$value =~ tr/+/ /;
$value =~ s/%(..)/pack("C", hex($1))/eg;
$FORM{$name} = $value;
}
# Extract the interesting ones
$core = $FORM{unit};
$timespan = $FORM{length};
# Generate page header
print "content-type: text/html\n\n";
print "
CQT utility consumption server
\n";
# Now, we need to check for validity of the core/timespan entry
# test if unit exists
$matches = grep $core eq $_, @allowedcores;
if ($matches != 1) {
print "
Logging failure
Sorry, logging for the requested unit is not (yet) implemented.
\n";
} else {
# test if we have proper value 0...3 for length
if ($timespan !~ /[0123]/) {
# by default, take a week
$timespan=1;
}
# For debugging
# $timespan=1;
# $core="AHU2";
# Prepare flexible arguments for gnuplot for different sizes
@datapoints = ( 1500, 10800, 46000, 120000);
@samplingdensity = (1, 10, 30, 120);
@outputformat = ("%m/%d\\n%H:%M", "%a\\n%m/%d\\n%H:%M", "%m/%d", "%d.%b");
$imagename = $core."_p_".$datapoints[$timespan].".png";
# compose parameter set for gnuplot
$parset="core=\"$core\"; num=$datapoints[$timespan]; evr=$samplingdensity[$timespan]; ofmt=\"$outputformat[$timespan]\"; outfilename=\"$imagename\"; logdir=\"$logdir\"; imgdir=\"$imgdir\" \n";
# generate image
open GNUPLOT, "| gnuplot - $gnudir/pressure.gnu >/dev/null";
print GNUPLOT $parset;
close GNUPLOT;
# Generate web page
print "
CHW differential pressure history
\n";
print "\n";
# Select other resolutions/ units
print "