Errand provides Ruby bindings for RRD functions (via librrd), and a clear API for interacting with RRDs.

Check under spec/ for usage examples.

To set up an RRD to work with (whether it exists or otherwise):

@rrd = Errand.new(:filename => "data.rrd")

To create an RRD:

@rrd.create(:sources => [
              {:name => "Counter", :type => :counter, :heartbeat => 1800, :min => 0, :max => 4294967295}],
            :archives => [
              {:function => :average, :xff => 0.5, :steps => 1, :rows => 2400}])

To update said RRD:

@rrd.update(:sources => [{:name => "Counter", :value => 1}]

To fetch that data:

@rrd.fetch # <= {:start => Time, :end => Time, 
                 :data => {"Counter" => [nil, nil, nil, 1]}

Errand requires RRDtool version 1.2 or later. Some RRD functions such as rrddump are only available with the latest RRDtool.

Installation is standard. If you've installed the gem, you should be ready to go.

Otherwise, simply run:

ruby extconf.rb
make
make install

This should build a library named rrd.so in the current directory. If it doesn't, please report bugs at http://github.com/eric/rubyrrdtool/issues!

Errand is managed by Jeweller, which generates the gemspec for you:

rake gemspec

Once the gemspec is generated, build the gem:

gem build errand.gemspec 

Testing is done with RSpec.

To run tests:

rake spec

• Extend documentation with examples

(the MIT license)

Copyright (c) 2006

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.