NAME
RRD::Simple - Simple interface to create and store data in RRD files
SYNOPSIS
use strict;
use RRD::Simple ();
# Create an interface object
my $rrd = RRD::Simple->new();
# Create a new RRD file with 3 data sources called
# bytesIn, bytesOut and faultsPerSec.
$rrd->create("myfile.rrd",
bytesIn => "GAUGE",
bytesOut => "GAUGE",
faultsPerSec => "COUNTER"
);
# Put some arbitary data values in the RRD file for same
# 3 data sources called bytesIn, bytesOut and faultsPerSec.
$rrd->update("myfile.rrd",
bytesIn => 10039,
bytesOut => 389,
faultsPerSec => 0.4
);
# Generate graphs:
# /var/tmp/myfile-daily.png, /var/tmp/myfile-weekly.png
# /var/tmp/myfile-monthly.png, /var/tmp/myfile-annual.png
my %rtn = $rrd->graph("myfile.rrd",
destination => "/var/tmp",
title => "Network Interface eth0",
vertical_label => "Bytes/Faults",
interlaced => ""
);
printf("Created %s\n",join(", ",map { $rtn{$_}->[0] } keys %rtn));
# Return information about an RRD file
my $info = $rrd->info("myfile.rrd");
require Data::Dumper;
print Data::Dumper::Dumper($info);
# Get unixtime of when RRD file was last updated
my $lastUpdated = $rrd->last("myfile.rrd");
print "myfile.rrd was last updated at " .
scalar(localtime($lastUpdated)) . "\n";
# Get list of data source names from an RRD file
my @dsnames = $rrd->sources("myfile.rrd");
print "Available data sources: " . join(", ", @dsnames) . "\n";
# And for the ultimately lazy, you could create and update
# an RRD in one go using a one-liner like this:
perl -MRRD::Simple=:all -e"update(@ARGV)" myfile.rrd bytesIn 99999
DESCRIPTION
RRD::Simple provides a simple interface to RRDTool's RRDs module. This module does not currently offer fetch
method that is available in the RRDs module.
It does however create RRD files with a sensible set of default RRA (Round Robin Archive) definitions, and can dynamically add new data source names to an existing RRD file.
This module is ideal for quick and simple storage of data within an RRD file if you do not need to, nor want to, bother defining custom RRA definitions.
METHODS
new
my $rrd = RRD::Simple->new(
rrdtool => "/usr/local/rrdtool-1.2.11/bin/rrdtool",
cf => [ qw(AVERAGE MAX) ],
default_dstype => "GAUGE",
);
The rrdtool
parameter is optional. It specifically defines where the rrdtool
binary can be found. If not specified, the module will search for the rrdtool
binary in your path, an additional location relative where the RRDs
module was loaded from, and in /usr/local/rrdtool*.
The rrdtool
binary is only used by the add_source
method, and only under certain circumstances. The add_source
method may also be called automatically by the update
method, if data point values for a previously undefined data source are provided for insertion.
The cf
parameter is optional, and defaults to AVERAGE and MAX. The cf
paramater defines which consolidation functions are used in round robin archives (RRAs) when creating new RRD files.
The default_dstype
parameter is optional. Specifying the default data source type (DST) through the new() method allows the DST to be localised to the $rrd object instance rather than be global to the RRD::Simple package. See $RRD::Simple::DEFAULT_DSTYPE.
create
$rrd->create($rrdfile, $period,
source_name => "TYPE",
source_name => "TYPE",
source_name => "TYPE"
);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
$period
is optional and will default to year
. Valid options are day
, week
, month
, year
, 3years
and mrtg
. Specifying a retention period value will change how long data will be retained for within the RRD file. The mrtg
scheme will try and mimic the retention period used by MRTG (http://people.ee.ethz.ch/~oetiker/webtools/mrtg/.
RRD::Simple will croak and die if you try to create an RRD file that already exists.
update
$rrd->update($rrdfile, $unixtime,
source_name => "VALUE",
source_name => "VALUE",
source_name => "VALUE"
);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
$unixtime
is optional and will default to time()
(the current unixtime). Specifying this value will determine the date and time that your data point values will be stored against in the RRD file.
If you try to update a value for a data source that does not exist, it will automatically be added for you. The data source type will be set to whatever is contained in the $RRD::Simple::DEFAULT_DSTYPE
variable. (See the VARIABLES section below).
If you explicitly do not want this to happen, then you should check that you are only updating pre-existing data source names using the sources
method. You can manually add new data sources to an RRD file by using the add_source
method, which requires you to explicitly set the data source type.
If you try to update an RRD file that does not exist, it will attept to create the RRD file for you using the same behaviour as described above. A warning message will be displayed indicating that the RRD file is being created for you if have perl warnings turned on.
last
my $unixtime = $rrd->last($rrdfile);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
sources
my @sources = $rrd->sources($rrdfile);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
add_source
$rrd->add_source($rrdfile,
source_name => "TYPE"
);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
You may add a new data source to an existing RRD file using this method. Only one data source name can be added at a time. You must also specify the data source type.
This method can be called internally by the update
method to automatically add missing data sources.
rename_source
$rrd->rename_source($rrdfile, "old_datasource", "new_datasource");
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
You may renames a data source in an existing RRD file using this method.
graph
my %rtn = $rrd->graph($rrdfile,
destination => "/path/to/write/graph/images",
basename => "graph_basename",
timestamp => "both", # graph, rrd, both or none
sources => [ qw(source_name1 source_name2 source_name3) ],
source_colors => [ qw(ff0000 aa3333 000000) ],
source_labels => [ ("My Source 1","My Source Two","Source 3") ],
source_drawtypes => [ qw(LINE1 AREA LINE) ],
line_thickness => 2,
extended_legend => 1,
rrd_graph_option => "value",
rrd_graph_option => "value",
rrd_graph_option => "value"
);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
Graph options specific to RRD::Simple are:
- destination
-
The
destination
parameter is optional, and it will default to the same path location as that of the RRD file specified by$rrdfile
. Specifying this value will force the resulting graph images to be written to this path location. (The specified path must be a valid directory with the sufficient permissions to write the graph images). - basename
-
The
basename
parameter is optional. This parameter specifies the basename of the graph image files that will be created. If not specified, tt will default to the name of the RRD file. For exmaple, if you specify a basename name ofmygraph
, the following graph image files will be created in thedestination
directory:mygraph-daily.png mygraph-weekly.png mygraph-monthly.png mygraph-annual.png
The default file format is
png
, but this can be explicitly specified using the standard RRDs options. (See below). - timestamp
-
my %rtn = $rrd->graph($rrdfile, timestamp => "graph", # graph, rrd, both or none );
The
timestamp
parameter is optional, but will default to "graph". This parameter specifies which "last upated" timestamps should be added to the bottom right hand corner of the graph.Valid values are: "graph" - the timestamp of when the graph was last updated will be used, "rrd" - the timestamp of when the RRD file was last updated will be used, "both" - both the timestamps of when the graph and RRD file were last updated will be used, "none" - no timestamp will be used.
- sources
-
The
sources
parameter is optional. This parameter should be an array of data source names that you want to be plotted. All data sources will be plotted by default. - source_colors
-
my %rtn = $rrd->graph($rrdfile, source_colors => [ qw(ff3333 ff00ff ffcc99) ], ); %rtn = $rrd->graph($rrdfile, source_colors => { source_name1 => "ff3333", source_name2 => "ff00ff", source_name3 => "ffcc99", }, );
The
source_colors
parameter is optional. This parameter should be an array or hash of hex triplet colors to be used for the plotted data source lines. A selection of vivid primary colors will be set by default. - source_labels
-
my %rtn = $rrd->graph($rrdfile, sources => [ qw(source_name1 source_name2 source_name3) ], source_labels => [ ("My Source 1","My Source Two","Source 3") ], ); %rtn = $rrd->graph($rrdfile, source_labels => { source_name1 => "My Source 1", source_name2 => "My Source Two", source_name3 => "Source 3", }, );
The
source_labels
parameter is optional. The parameter should be an array or hash of labels to be placed in the legend/key underneath the graph. An array can only be used if thesources
parameter is also specified, since the label index position in the array will directly relate to the data source index position in thesources
array.The data source names will be used in the legend/key by default if no
source_labels
parameter is specified. - source_drawtypes
-
my %rtn = $rrd->graph($rrdfile, source_drawtypes => [ qw(LINE1 AREA LINE) ], ); %rtn = $rrd->graph($rrdfile, source_colors => { source_name1 => "LINE1", source_name2 => "AREA", source_name3 => "LINE", }, ); %rtn = $rrd->graph($rrdfile, sources => [ qw(system user iowait idle) ] source_colors => [ qw(AREA STACK STACK STACK) ], );
The
source_drawtypes
parameter is optional. This parameter should be an array or hash of drawing/plotting types to be used for the plotted data source lines. By default all data sources are drawn as lines (LINE), but data sources may also be drawn as filled areas (AREA). Valid values are, LINE, LINEn (where n represents the thickness of the line in pixels), AREA or STACK. - line_thickness
-
Specifies the thickness of the data lines drawn on the graphs for any data sources that have not had a specific line thinkness already specified using the
source_drawtypes
option. Valid values are 1, 2 and 3 (pixels). - extended_legend
-
Prints more detailed information in the graph legend by adding the minimum, maximum and last values recorded on the graph for each data source.
Common RRD graph options are:
- title
-
A horizontal string at the top of the graph.
- vertical_label
-
A vertically placed string at the left hand side of the graph.
- width
-
The width of the canvas (the part of the graph with the actual data and such). This defaults to 400 pixels.
- height
-
The height of the canvas (the part of the graph with the actual data and such). This defaults to 100 pixels.
For examples on how to best use the graph
method, refer to the example scripts that are bundled with this module in the examples/ directory. A complete list of parameters can be found at http://people.ee.ethz.ch/~oetiker/webtools/rrdtool/doc/index.en.html.
retention_period
my $seconds = $rrd->retention_period($rrdfile);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
This method will return a maximum period of time (in seconds) that the RRD file will store data for.
info
my $info = $rrd->info($rrdfile);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
This method will return a complex data structure containing details about the RRD file, including RRA and data source information.
heartbeat
my $heartbeat = $rrd->heartbeat($rrdfile, "dsname");
my @rtn = $rrd->heartbeat($rrdfile, "dsname", 600);
$rrdfile
is optional and will default to $0.rrd
. (Script basename with the file extension of .rrd).
This method will return the current heartbeat of a data source, or set a new heartbeat of a data source.
VARIABLES
$RRD::Simple::DEBUG
Debug and trace information will be printed to STDERR if this variable if set to 1 (boolean true).
This variable will take its value from $ENV{DEBUG}
, if it exists, otherwise it will default to 0 (boolean false). This is a normal package variable and may be safely modified at any time.
$RRD::Simple::DEFAULT_DSTYPE
This variable is used as the default data source type when creating or adding new data sources, when no other data source type is explicitly specified.
This variable will take its value from $ENV{DEFAULT_DSTYPE}
, if it exists, otherwise it will default to GAUGE
. This is a normal package variable and may be safely modified at any time.
EXPORTS
You can export the following functions if you do not wish to go through the extra effort of using the OO interface:
create
update
last_update (synonym for the last() method)
sources
add_source
rename_source
graph
retention_period
info
heartbeat
The tag all
is available to easily export everything:
use RRD::Simple qw(:all);
See the examples and unit tests in this distribution for more details.
SEE ALSO
RRDTool::OO, RRDs, http://www.rrdtool.org, examples/*.pl, http://search.cpan.org/src/NICOLAW/RRD-Simple-1.41/examples/, http://rrd.me.uk
VERSION
$Id: Simple.pm 945 2007-02-11 14:43:10Z nicolaw $
AUTHOR
Nicola Worthington <nicolaw@cpan.org>
If you like this software, why not show your appreciation by sending the author something nice from her Amazon wishlist? ( http://www.amazon.co.uk/gp/registry/1VZXC59ESWYK0?sort=priority )
COPYRIGHT
Copyright 2005,2006,2007 Nicola Worthington.
This software is licensed under The Apache Software License, Version 2.0.