Munin contributed plugins

    [currentcost]

    env.device          /dev/ttyUSB0

    env.baud            2400

    env.tick            6

    env.currency        £

    env.rate1           13.9

    nenv.rate1qty       900

    env.rate2           8.2

    env.nightrate       0

    env.nighthours      23:30-06:30

    env.standingcharge  0.0

    env.metertype       CC128

=item env.metertype

The type of the meter. Currently "CC128" and "CC02" are supported.

 #%# family=auto contrib

 #%# capabilities=multigraph autoconf

my $device_node    = $ENV{device}         || "/dev/ttyUSB0";

my $baud_rate      = $ENV{baud}           || "2400";    # or 9600 or 57600

my $tick_rate      = $ENV{tick}           || "6";

my $currency       = $ENV{currency}       || "£";       # £ or €

my $rate1          = $ENV{rate1}          || "13.9";    # in pence/cents

my $rate1qty       = $ENV{rate1qty}       || "900";     # in kWh, 0 to use fixed rate2

my $rate2          = $ENV{rate2}          || "8.2";     # in pence/cents

my $nightrate      = $ENV{nightrate}      || "0";       # 0 = disabled

my $nighthours     = $ENV{nighthours}     || "23:30-06:30";

my $standingcharge = $ENV{standingcharge} || "0.0";     # pence/cents per month

my $metertype      = $ENV{metertype}      || "CC128";   # or "CC02"

my $MUNIN_DEBUG    = $ENV{MUNIN_DEBUG}    || 0;         # Set by munin-run

        print "# Saving Data (Data is "

          . ( time - Time::Local::timelocal(@lastread) )

          . " seconds old)\n"

          if $MUNIN_DEBUG;

        print "# Data is stale ("

          . ( time - Time::Local::timelocal(@lastread) )

          . " seconds). Re-reading device\n"

          if $MUNIN_DEBUG;

            my @temparray;

            if ( $metertype eq "CC128" ) {

                @temparray = collect_cc128_data( $device_node, $baud_rate );

            }

            elsif ( $metertype eq "CC02" ) {

                @temparray = collect_cc02_data( $device_node, $baud_rate );

            }

            else {

                die "Unknown meter type $metertype.";

            }

            # Read the time so we know whether to reset

            #  daily/monthly/yearly counters

                                print "# Start of a new $period period." .

							          " Resetting counter\n" if $MUNIN_DEBUG;

        print "# Night rate is ACTIVE\n" if $MUNIN_DEBUG;

        print "# Night rate is enabled, but NOT active\n" if $MUNIN_DEBUG;

As per L<http://cumbers.wordpress.com/2008/05/07/breakdown-of-currentcost-xml-output/>:

        <dsb>00014</dsb>        days since birth

        <hr>14</hr>             the time

        <name>CC02</name>       name of this device

        <id>03280</id>          communication channel for device

        <type>1</type>          hardware version of the device

        <sver>0.07</sver>       software version

        <watts>00080</watts>    value from the first channel clamp

        <watts>00000</watts>    value from the second channel clamp

        <watts>00000</watts>    value from the third channel clamp

    <tmpr>28.8</tmpr>           current temperature (degrees celsius)

            <h02>000.0</h02>    total Kwh used in 2 hour blocks

            <d01>0000</d01>     total Kwh used per day(s)

            <m01>0000</m01>     total Kwh used per month(s)

            <y1>0000000</y1>    total Kwh used per year(s)

        print "# Read from device: $_\n" if $MUNIN_DEBUG;

            print "# Parsing Sensor $sensor\n" if $MUNIN_DEBUG;

                print "# Hello again, Sensor $sensor\n" if $MUNIN_DEBUG;

                    print "# Channel $channel, Unit $unit, Value $val\n"

                      if $MUNIN_DEBUG;

                    push @temparr,

                      {

                        "channel" => $channel,

                        "unit"    => $unit,

                        "value"   => $val

                      };

                }

            }

            $temphash->{data} = \@temparr;

            push @cc_data_arr, $temphash;

        }

    }

    close($ttydev);

    return @cc_data_arr;

}

sub collect_cc02_data {

    # Function supplied by David Edmondson <dme@dme.org>

    # Read data from the serial port

    my ( $port, $baud ) = @_;

    my $tty = Device::SerialPort->new($port) || die "Can't open $port: $!";

    $tty->baudrate($baud)   || die "Can't set serial baudrate";

    $tty->parity("none")    || die "Can't set serial parity";

    $tty->databits(8)       || die "Can't set serial databits";

    $tty->handshake("none") || die "Can't set serial handshake";

    $tty->write_settings    || die "Can't set serial parameters";

    open( my $ttydev, "<", $port ) || die "Can't open $port: $?";

    my @cc_data_arr;

    while (<$ttydev>) {

        if (m{(<msg>.*</msg>)}) {

            my $xmlref = XML::Simple::XMLin( $1, KeepRoot => 1 );

            my $temphash;

            $temphash->{sensor} = 0;    # Only one sensor.

            $temphash->{temp}   = $xmlref->{msg}->{tmpr};

            my @temparr;

            foreach my $key ( keys %{ $xmlref->{msg} } ) {

                if ( $key =~ /ch(\d+)/ ) {

                    my $channel = $1;

                    my $unit = ( keys %{ $xmlref->{msg}->{"ch$channel"} } )[0];

                    my $val  = $xmlref->{msg}->{"ch$channel"}->{$unit};

            last;

"# Conflicting units ($unit and $key->{unit}) on sensor $datum->{sensor}";

                }

                else {

                    print "${fieldname}_t.cdef ${fieldname},3600,TRENDNAN\n";

                }

            print <<EOF;