log::log4perl::filter::boolean(3) [suse man page]
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)
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Config(3pm) User Contributed Perl Documentation Config(3pm) NAME
Log::Log4perl::Config - Log4perl configuration file syntax DESCRIPTION
In "Log::Log4perl", configuration files are used to describe how the system's loggers ought to behave. The format is the same as the one as used for "log4j", just with a few perl-specific extensions, like enabling the "Bar::Twix" syntax instead of insisting on the Java-specific "Bar.Twix". Comment lines (starting with arbitrary whitespace and a #) and blank lines (all whitespace or empty) are ignored. Also, blanks between syntactical entities are ignored, it doesn't matter if you write log4perl.logger.Bar.Twix=WARN,Screen or log4perl.logger.Bar.Twix = WARN, Screen "Log::Log4perl" will strip the blanks while parsing your input. Assignments need to be on a single line. However, you can break the line if you want to by using a continuation character at the end of the line. Instead of writing log4perl.appender.A1.layout=Log::Log4perl::Layout::SimpleLayout you can break the line at any point by putting a backslash at the very (!) end of the line to be continued: log4perl.appender.A1.layout= Log::Log4perl::Layout::SimpleLayout Watch out for trailing blanks after the backslash, which would prevent the line from being properly concatenated. Loggers Loggers are addressed by category: log4perl.logger.Bar.Twix = WARN, Screen This sets all loggers under the "Bar::Twix" hierarchy on priority "WARN" and attaches a later-to-be-defined "Screen" appender to them. Settings for the root appender (which doesn't have a name) can be accomplished by simply omitting the name: log4perl.logger = FATAL, Database, Mailer This sets the root appender's level to "FATAL" and also attaches the later-to-be-defined appenders "Database" and "Mailer" to it. The additivity flag of a logger is set or cleared via the "additivity" keyword: log4perl.additivity.Bar.Twix = 0|1 (Note the reversed order of keyword and logger name, resulting from the dilemma that a logger name could end in ".additivity" according to the log4j documentation). Appenders and Layouts Appender names used in Log4perl configuration file lines need to be resolved later on, in order to define the appender's properties and its layout. To specify properties of an appender, just use the "appender" keyword after the "log4perl" intro and the appender's name: # The Bar::Twix logger and its appender log4perl.logger.Bar.Twix = DEBUG, A1 log4perl.appender.A1=Log::Log4perl::Appender::File log4perl.appender.A1.filename=test.log log4perl.appender.A1.mode=append log4perl.appender.A1.layout=Log::Log4perl::Layout::SimpleLayout This sets a priority of "DEBUG" for loggers in the "Bar::Twix" hierarchy and assigns the "A1" appender to it, which is later on resolved to be an appender of type "Log::Log4perl::Appender::File", simply appending to a log file. According to the "Log::Log4perl::Appender::File" manpage, the "filename" parameter specifies the name of the log file and the "mode" parameter can be set to "append" or "write" (the former will append to the logfile if one with the specified name already exists while the latter would clobber and overwrite it). The order of the entries in the configuration file is not important, "Log::Log4perl" will read in the entire file first and try to make sense of the lines after it knows the entire context. You can very well define all loggers first and then their appenders (you could even define your appenders first and then your loggers, but let's not go there): log4perl.logger.Bar.Twix = DEBUG, A1 log4perl.logger.Bar.Snickers = FATAL, A2 log4perl.appender.A1=Log::Log4perl::Appender::File log4perl.appender.A1.filename=test.log log4perl.appender.A1.mode=append log4perl.appender.A1.layout=Log::Log4perl::Layout::SimpleLayout log4perl.appender.A2=Log::Log4perl::Appender::Screen log4perl.appender.A2.stderr=0 log4perl.appender.A2.layout=Log::Log4perl::Layout::PatternLayout log4perl.appender.A2.layout.ConversionPattern = %d %m %n Note that you have to specify the full path to the layout class and that "ConversionPattern" is the keyword to specify the printf-style formatting instructions. Configuration File Cookbook Here's some examples of often-used Log4perl configuration files: Append to STDERR log4perl.category.Bar.Twix = WARN, Screen log4perl.appender.Screen = Log::Log4perl::Appender::Screen log4perl.appender.Screen.layout = Log::Log4perl::Layout::PatternLayout log4perl.appender.Screen.layout.ConversionPattern = %d %m %n Append to STDOUT log4perl.category.Bar.Twix = WARN, Screen log4perl.appender.Screen = Log::Log4perl::Appender::Screen log4perl.appender.Screen.stderr = 0 log4perl.appender.Screen.layout = Log::Log4perl::Layout::PatternLayout log4perl.appender.Screen.layout.ConversionPattern = %d %m %n Append to a log file log4perl.logger.Bar.Twix = DEBUG, A1 log4perl.appender.A1=Log::Log4perl::Appender::File log4perl.appender.A1.filename=test.log log4perl.appender.A1.mode=append log4perl.appender.A1.layout = Log::Log4perl::Layout::PatternLayout log4perl.appender.A1.layout.ConversionPattern = %d %m %n Note that you could even leave out log4perl.appender.A1.mode=append and still have the logger append to the logfile by default, although the "Log::Log4perl::Appender::File" module does exactly the opposite. This is due to some nasty trickery "Log::Log4perl" performs behind the scenes to make sure that beginner's CGI applications don't clobber the log file every time they're called. Write a log file from scratch If you loathe the Log::Log4perl's append-by-default strategy, you can certainly override it: log4perl.logger.Bar.Twix = DEBUG, A1 log4perl.appender.A1=Log::Log4perl::Appender::File log4perl.appender.A1.filename=test.log log4perl.appender.A1.mode=write log4perl.appender.A1.layout=Log::Log4perl::Layout::SimpleLayout "write" is the "mode" that has "Log::Log4perl::Appender::File" explicitely clobber the log file if it exists. SEE ALSO
Log::Log4perl::Config::PropertyConfigurator Log::Log4perl::Config::DOMConfigurator Log::Log4perl::Config::LDAPConfigurator (coming soon!) 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 v5.10.1 2010-07-21 Config(3pm)