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Log::Fine - Yet another logging framework


Provides fine-grained logging and tracing.

    use Log::Fine;
    use Log::Fine::Levels::Syslog;                # exports log levels
    use Log::Fine::Levels::Syslog qw( :masks );   # exports masks and levels

    # Build a Log::Fine object
    my $fine = Log::Fine->new();

    # Specify a custom map
    my $fine = Log::Fine->new(levelmap => "Syslog");

    # Get the name of the log object
    my $name = $fine->name();

    # Use logger() to get a new logger object.  If "foo" is not
    # defined then a new logger with the name "foo" will be created.
    my $log = Log::Fine->logger("foo");

    # Get list of names of defined logger objects
    my @loggers = $log->listLoggers();

    # Register a handle, in this case a handle that logs to console.
    my $handle = Log::Fine::Handle::Console->new();
    $log->registerHandle( $handle );

    # Log a message
    $log->log(INFO, "Log object successfully initialized");


Log::Fine provides a logging framework for application developers who need a fine-grained logging mechanism in their program(s). By itself, Log::Fine provides a mechanism to get one or more logging objects (called loggers) from its stored namespace. Most logging is then done through a logger object that is specific to the application.

For a simple functional interface to the logging sub-system, see Log::Fine::Utils.


Handlers provides a means to output log messages in one or more ways. Currently, the following handles are provided:

See the relevant perldoc information for more information. Additional handlers can be defined to user taste.


A formatter specifies how Log::Fine displays messages. When a message is logged, it gets passed through a formatter object, which adds any additional information such as a time-stamp or caller information.

By default, log messages are formatted as follows using the Basic formatter object.

     [<time>] <LEVEL> <MESSAGE>

For more information on the customization of log messages, see Log::Fine::Formatter.


To install Log::Fine:

  perl Makefile.PL
  make test
  make install


The Log::Fine module, by itself, provides getters & setter methods for loggers and level classes. After a logger is created, further actions are done through the logger object. The following two constructors are defined:


Creates a new Log::Fine object.


A hash with the following keys

  • levelmap

    [default: Syslog] Name of level map to use. See Log::Fine::Levels for further details

  • no_croak

    [optional] If set to true, then do not croak when _error is called.

  • err_callback

    [optional] If defined to a valid CODE ref, then this subroutine will be called instead of _fatal when _error is called.


The newly blessed object


Provides list of currently defined loggers




Array containing list of currently defined loggers


Getter for the global level map.


A Log::Fine::Levels subclass


Getter/Constructor for a logger object.


  • logger name

    The name of the logger object. If the specified logger object does not exist, then a new one will be created.


an Log::Fine::Logger object


Getter for name of object




String containing name of object, otherwise undef


Private internal method that is called when an error condition is encountered. Will call _fatal unless {no_croak} is defined.

This method can be overridden per taste.



Message passed to confess.


Private internal method that is called when a fatal (non-recoverable) condition is encountered. Calls confess with given error message.

While this method can be overridden, this is generally not advised.



Message passed to confess.


I'd like the thank the following people for either inspiration or past work on logging: Josh Glover for his work as well as teaching me all I know about object-oriented programming in perl. Dan Boger for taking the time and patience to review this code and offer his own suggestions. Additional thanks to Tom Maher and Chris Josephs for encouragement.

The following logging frameworks provided inspiration for parts of Log::Fine.

  • Dave Rolsky's Log::Dispatch module

  • Sun Microsystem's java.utils.logging framework

  • The Python logging package


Please report any bugs or feature requests to bug-log-fine at, or through the web interface at I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.


You can find documentation for this module with the perldoc command.

    perldoc Log::Fine

You can also look for information at:


Want to contribute? The source code repository for Log::Fine is now available at To clone your own copy:

  $ git clone git://

Signed patches generated by git-format-patch(1) may be submitted via email.


Christopher M. Fuhrman, <cfuhrman at>


perl, syslog, Log::Fine::Handle, Log::Fine::Formatter, Log::Fine::Logger, Log::Fine::Utils, Sys::Syslog


Copyright (c) 2008-2011, 2013 Christopher M. Fuhrman, All rights reserved.

This program is free software licensed under the...

        The BSD License

The full text of the license can be found in the LICENSE file included with this module.