Listing 10. nagios/lib/puppet/parser/functions/purge_exported.rb

# This function will be used by the exported
# resources collector (the nagios box)
Puppet::Parser::Functions::newfunction(:purge_exported,:doc => "delete expired resources.") do |args|

  require 'rubygems'
  require 'pg'
  require 'puppet'

  raise Puppet::ParseError, "Missing hostname." if args.empty?
  hosts = args.flatten

  begin
    conn = PGconn.open(:dbname => 'puppet', :user => 'postgres')

    hosts.each do |host|

      Puppet.notice("Purging expired resources for host: #{host}")
      conn.exec("SELECT id FROM hosts WHERE name = \'#{host}\'") do |host_id|

        raise "Too many hosts" if host_id.ntuples > 1
        conn.exec("SELECT id FROM resources WHERE host_id = #{host_id.values.flatten[0].to_i}") do |results|

          resource_ids = []
          results.each do |row|
            resource_ids << Hash[*row.to_a.flatten]
          end

          resource_ids.each do |resource|
            conn.exec("DELETE FROM param_values WHERE resource_id = #{resource['id']}")
            conn.exec("DELETE FROM resources WHERE id = #{resource['id']}")
          end
        end

        conn.exec("DELETE FROM hosts WHERE id = #{host_id.values}")
      end
    end
  rescue => e
    Puppet.notice(e.message)
  ensure
    conn.close
  end
end