|
|
Solido Spam Filter 4.0 build 100 (Default branch)
09-10-2008
|
|
Filter::Boolean(3) User Contributed Perl Documentation Filter::Boolean(3) NAME
Log::Log4perl::Filter::Boolean - Special filter to combine the results of others SYNOPSIS
log4perl.logger = WARN, AppWarn, AppError log4perl.filter.Match1 = sub { /let this through/ } log4perl.filter.Match2 = sub { /and that, too/ } log4perl.filter.MyBoolean = Log::Log4perl::Filter::Boolean log4perl.filter.MyBoolean.logic = Match1 || Match2 log4perl.appender.Screen = Log::Dispatch::Screen log4perl.appender.Screen.Filter = MyBoolean log4perl.appender.Screen.layout = Log::Log4perl::Layout::SimpleLayout DESCRIPTION
Sometimes, it's useful to combine the output of various filters to arrive at a log/no log decision. While Log4j, Log4perl's mother ship, chose to implement this feature as a filter chain, similar to Linux' IP chains, Log4perl tries a different approach. Typically, filter results will not need to be passed along in chains but combined in a programmatic manner using boolean logic. "Log if this filter says 'yes' and that filter says 'no'" is a fairly common requirement but hard to implement as a chain. "Log::Log4perl::Filter::Boolean" is a special predefined custom filter for Log4perl which combines the results of other custom filters in arbitrary ways, using boolean expressions: log4perl.logger = WARN, AppWarn, AppError log4perl.filter.Match1 = sub { /let this through/ } log4perl.filter.Match2 = sub { /and that, too/ } log4perl.filter.MyBoolean = Log::Log4perl::Filter::Boolean log4perl.filter.MyBoolean.logic = Match1 || Match2 log4perl.appender.Screen = Log::Dispatch::Screen log4perl.appender.Screen.Filter = MyBoolean log4perl.appender.Screen.layout = Log::Log4perl::Layout::SimpleLayout "Log::Log4perl::Filter::Boolean"'s boolean expressions allow for combining different appenders by name using AND (&& or &), OR (|| or |) and NOT (!) as logical expressions. Parentheses are used for grouping. Precedence follows standard Perl. Here's a bunch of examples: Match1 && !Match2 # Match1 and not Match2 !(Match1 || Match2) # Neither Match1 nor Match2 (Match1 && Match2) || Match3 # Both Match1 and Match2 or Match3 SEE ALSO
Log::Log4perl::Filter, Log::Log4perl::Filter::LevelMatch, Log::Log4perl::Filter::LevelRange, Log::Log4perl::Filter::StringRange COPYRIGHT AND LICENSE
Copyright 2002-2009 by Mike Schilli <m@perlmeister.com> and Kevin Goess <cpan@goess.org>. This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.12.1 2010-02-07 Filter::Boolean(3)