NAME

       Smokeping::matchers::base - Base Class for implementing SmokePing Matchers

OVERVIEW

       This is the base class for writing SmokePing matchers. Every matcher must inherit from the
       base class and provide it's own methods for the 'business' logic.

       Note that the actual matchers must have at least one capital letter in their name, to
       differentiate them from the base class(es).

DESCRIPTION

       Every matcher must provide the following methods:

   new
       The new method expects hash elements as an argument eg new({x=>'\d+',y=>'\d+'},x=>1,y=>2).
       The first part is a syntax rule for the arguments it should expect and the second part are
       the arguments itself. The first part will be supplied by the child class as it calls the
       parent method.

   Length
       The Length method returns the number of values the matcher will expect from SmokePing.
       This method must be overridden by the children of the base class.

   Desc
       Simply return the description of the function. This method must be overwritten by a
       children of the base class.

   Test
       Run the matcher and return true or false. The Test method is called with a hash containing
       two arrays giving it access to both rtt and loss values.

         my $data=shift;
         my @rtt = @{$data->{rtt}};
         my @loss = @{$data->{loss}};

       The arrays are ordered from old to new.

         @rdd[old..new]

       There may be more than the expected number of elements in this array. Address them with
       $x[-1] to $x[-max].

       There's also a key called 'prevmatch' in the hash. It contains the value returned by the
       previous call of the 'Test' method. This allows for somewhat more intelligent alerting due
       to state awareness.

         my $prevmatch = $data->{prevmatch};

COPYRIGHT

       Copyright (c) 2004 by OETIKER+PARTNER AG. All rights reserved.

LICENSE

       This program is free software; you can redistribute it and/or modify it under the terms of
       the GNU General Public License as published by the Free Software Foundation; either
       version 2 of the License, or (at your option) any later version.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
       without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
       See the GNU General Public License for more details.

       You should have received a copy of the GNU General Public License along with this program;
       if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
       USA.

AUTHOR

       Tobias Oetiker <tobi@oetiker.ch>