=encoding utf8

=head1 NAME

Log::Report::Dispatcher::Log4perl - send messages to Log::Log4perl back-end

=head1 INHERITANCE

 Log::Report::Dispatcher::Log4perl
   is a Log::Report::Dispatcher

=head1 SYNOPSIS

 # start using log4perl via a config file
 # The name of the dispatcher is the name of the default category.
 dispatcher LOG4PERL => 'logger'
   , accept => 'NOTICE-'
   , config => "$ENV{HOME}/.log.conf";

 # disable default dispatcher
 dispatcher close => 'logger';

 # configuration inline, not in file: adapted from the Log4perl manpage
 my $name    = 'logger';
 my $outfile = '/tmp/a.log';
 my $config  = <<__CONFIG;
 log4perl.category.$name            = INFO, Logfile
 log4perl.logger.Logfile          = Log::Log4perl::Appender::File
 log4perl.logger.Logfile.filename = $outfn
 log4perl.logger.Logfile.layout   = Log::Log4perl::Layout::PatternLayout
 log4perl.logger.Logfile.layout.ConversionPattern = %d %F{1} %L> %m
 __CONFIG

 dispatcher LOG4PERL => $name, config => \$config;

=head1 DESCRIPTION

This dispatchers produces output tot syslog, based on the C<Sys::Log4perl>
module (which will not be automatically installed for you).

Extends L<"DESCRIPTION" in Log::Report::Dispatcher|Log::Report::Dispatcher/"DESCRIPTION">.
 
=head2 Reasons <--> Levels

The REASONs for a message in L<Log::Report|Log::Report> are names quite similar to
the log levels used by Log::Log4perl.  The default mapping is list
below.  You can change the mapping using L<new(to_level)|Log::Report::Dispatcher::Log4perl/"Constructors">.

  TRACE   => $DEBUG    ERROR   => $ERROR
  ASSERT  => $DEBUG    FAULT   => $ERROR
  INFO    => $INFO     ALERT   => $FATAL
  NOTICE  => $INFO     FAILURE => $FATAL
  WARNING => $WARN     PANIC   => $FATAL
  MISTAKE => $WARN

=head2 Categories

C<Log::Report> uses text-domains for translation tables.  These are
also used as categories for the Log4perl infrastructure.  So, typically
every module start with:

   use Log::Report 'my-text-domain', %more_options;

Now, if there is a logger inside the log4perl configuration which is
named 'my-text-domain', that will be used.  Otherwise, the name of the
dispatcher is used to select the logger.

=head3 Limitiations

The global C<$caller_depth> concept of Log::Log4perl is broken.
That variable is used to find the filename and line number of the logged
messages.  But these messages may have been caught, rerouted, eval'ed, and
otherwise followed a unpredictable multi-leveled path before it reached
the Log::Log4perl dispatcher.  This means that layout patterns C<%F>
and C<%L> are not useful in the generic case, maybe in your specific case.

=head1 METHODS

Extends L<"METHODS" in Log::Report::Dispatcher|Log::Report::Dispatcher/"METHODS">.
 
=head2 Constructors

Extends L<"Constructors" in Log::Report::Dispatcher|Log::Report::Dispatcher/"Constructors">.
 
=over 4

=item $obj-E<gt>B<close>()

Inherited, see L<Log::Report::Dispatcher/"Constructors">

=item Log::Report::Dispatcher::Log4perl-E<gt>B<new>($type, $name, %options)

The Log::Log4perl infrastructure has all settings in a configuration
file.  In that file, you should find a category with the $name.

 -Option       --Defined in             --Default
  accept         Log::Report::Dispatcher  'ALL'
  charset        Log::Report::Dispatcher  <undef>
  config                                  <undef>
  format_reason  Log::Report::Dispatcher  'LOWERCASE'
  locale         Log::Report::Dispatcher  <system locale>
  mode           Log::Report::Dispatcher  'NORMAL'
  to_level                                []

=over 2

=item accept => REASONS

=item charset => CHARSET

=item config => FILENAME|SCALAR

When a SCALAR reference is passed in, that must refer to a string which
contains the configuration text.  Otherwise, specify an existing FILENAME.

By default, it is expected that Log::Log4perl has been initialized
externally.  That module uses global variables to communicate, which
should be present before any logging is attempted.

=item format_reason => 'UPPERCASE'|'LOWERCASE'|'UCFIRST'|'IGNORE'|CODE

=item locale => LOCALE

=item mode => 'NORMAL'|'VERBOSE'|'ASSERT'|'DEBUG'|0..3

=item to_level => ARRAY-of-PAIRS

See L<reasonToLevel()|Log::Report::Dispatcher::Log4perl/"Logging">.

=back

=back

=head2 Accessors

Extends L<"Accessors" in Log::Report::Dispatcher|Log::Report::Dispatcher/"Accessors">.
 
=over 4

=item $obj-E<gt>B<isDisabled>()

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=item $obj-E<gt>B<logger>( [$domain] )

Returns the Log::Log4perl::Logger object which is used for logging.
When there is no specific logger for this $domain (logger with the exact
name of the $domain) the default logger is being used, with the name of
this dispatcher.

=item $obj-E<gt>B<mode>()

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=item $obj-E<gt>B<name>()

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=item $obj-E<gt>B<needs>( [$reason] )

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=item $obj-E<gt>B<type>()

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=back

=head2 Logging

Extends L<"Logging" in Log::Report::Dispatcher|Log::Report::Dispatcher/"Logging">.
 
=over 4

=item $obj-E<gt>B<addSkipStack>(@CODE)

=item Log::Report::Dispatcher::Log4perl-E<gt>B<addSkipStack>(@CODE)

Inherited, see L<Log::Report::Dispatcher/"Logging">

=item $obj-E<gt>B<collectLocation>()

=item Log::Report::Dispatcher::Log4perl-E<gt>B<collectLocation>()

Inherited, see L<Log::Report::Dispatcher/"Logging">

=item $obj-E<gt>B<collectStack>( [$maxdepth] )

=item Log::Report::Dispatcher::Log4perl-E<gt>B<collectStack>( [$maxdepth] )

Inherited, see L<Log::Report::Dispatcher/"Logging">

=item $obj-E<gt>B<log>(HASH-$of-%options, $reason, $message, $domain)

Inherited, see L<Log::Report::Dispatcher/"Logging">

=item $obj-E<gt>B<reasonToLevel>($reason)

Returns a level which is understood by Log::Dispatch, based on
a translation table.  This can be changed with L<new(to_level)|Log::Report::Dispatcher::Log4perl/"Constructors">.

example: 

 use Log::Log4perl     qw/:levels/;

 # by default, ALERTs are output as $FATAL
 dispatcher Log::Log4perl => 'logger'
   , to_level => [ ALERT => $ERROR, ]
   , ...;

=item $obj-E<gt>B<skipStack>()

Inherited, see L<Log::Report::Dispatcher/"Logging">

=item $obj-E<gt>B<stackTraceLine>(%options)

=item Log::Report::Dispatcher::Log4perl-E<gt>B<stackTraceLine>(%options)

Inherited, see L<Log::Report::Dispatcher/"Logging">

=item $obj-E<gt>B<translate>(HASH-$of-%options, $reason, $message)

Inherited, see L<Log::Report::Dispatcher/"Logging">

=back

=head1 DETAILS

Extends L<"DETAILS" in Log::Report::Dispatcher|Log::Report::Dispatcher/"DETAILS">.
 
=head1 SEE ALSO

This module is part of Log-Report distribution version 1.26,
built on January 23, 2018. Website: F<http://perl.overmeer.net/CPAN/>

=head1 LICENSE

Copyrights 2007-2018 by [Mark Overmeer]. For other contributors see ChangeLog.

This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
See F<http://dev.perl.org/licenses/>

