Log::Agent::Channel::Handle - I/O handle logging channel for Log::Agent

Log-Agent documentation Contained in the Log-Agent distribution.

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NAME

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Log::Agent::Channel::Handle - I/O handle logging channel for Log::Agent

SYNOPSIS

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 require Log::Agent::Channel::Handle;

 my $driver = Log::Agent::Channel::Handle->make(
     -prefix     => "prefix",
     -stampfmt   => "own",
     -showpid    => 1,
     -handle     => \*FILE,
 );

DESCRIPTION

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The handle channel performs logging to an already opened I/O handle, along with the necessary prefixing and stamping of the messages.

The creation routine make() takes the following arguments:

-handle => handle

Specifies the I/O handle to use. It can be given as a GLOB reference, such as \*FILE, or as an IO::Handle object.

NOTE: Auto-flushing is not enabled on the handle. Even when the channel is closed, the handle is left as-is: we simply stop sending log messages to it.

-no_newline => flag

When set to true, never append any "\n" (on Unix) or "\r\n" (on Windows) to log messages.

Internally, Log::Agent relies on the channel to delimit logged lines appropriately, so this flag is not used. However, it might be useful for Log::Agent::Logger users.

Default is false, meaning newline markers are systematically appended.

-no_prefixing => flag

When set to true, disable the prefixing logic entirely, i.e. the following options are ignored completely: -prefix, -showpid, -no_ucfirst, -stampfmt.

Default is false.

-no_ucfirst => flag

When set to true, don't upper-case the first letter of the log message entry when there's no prefix inserted before the logged line. When there is a prefix, a ":" character follows, and therefore the leading letter of the message should not be upper-cased anyway.

Default is false, meaning uppercasing is performed.

-prefix => prefix

The application prefix string to prepend to messages.

-showpid => flag

If set to true, the PID of the process will be appended within square brackets after the prefix, to all messages.

Default is false.

-stampfmt => (name | CODE)

Specifies the time stamp format to use. By default, my "own" format is used. See Log::Agent::Stamping for a description of the available format names.

You may also specify a CODE ref: that routine will be called every time we need to compute a time stamp. It should not expect any parameter, and should return a string.

CAVEAT

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Beware of chdir(). If your program uses chdir(), you should always specify logfiles by using absolute paths, otherwise you run the risk of having your relative paths become invalid: there is no anchoring done at the time you specify them. This is especially true when configured for rotation, since the logfiles are recreated as needed and you might end up with many logfiles scattered throughout all the directories you chdir()ed to.

AUTHOR

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Raphael Manfredi <Raphael_Manfredi@pobox.com>

SEE ALSO

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Log::Agent::Logger(3), Log::Agent::Channel(3).

Log-Agent documentation Contained in the Log-Agent distribution. 
#
# $Id: Handle.pm,v 1.1 2002/03/09 16:06:26 wendigo Exp $
#
#  Copyright (c) 1999, Raphael Manfredi
#  
#  You may redistribute only under the terms of the Artistic License,
#  as specified in the README file that comes with the distribution.
#
# HISTORY
# $Log: Handle.pm,v $
# Revision 1.1  2002/03/09 16:06:26  wendigo
# New maintainer
#
# Revision 0.2.1.1  2001/03/31 10:00:16  ram
# patch7: fixed =over to add explicit indent level
#
# Revision 0.2  2000/11/06 19:30:32  ram
# Baseline for second Alpha release.
#
# $EndLog$
#

use strict;
require Log::Agent::Channel;
require Log::Agent::Prefixer;
require Log::Agent::File::Native;

########################################################################
package Log::Agent::Channel::Handle;

use vars qw(@ISA);

@ISA = qw(Log::Agent::Channel Log::Agent::Prefixer);

use Log::Agent::Stamping;

#
# ->make			-- defined
#
# Creation routine.
#
# Attributes (and switches that set them):
#
# prefix		the application name
# stampfmt		stamping format ("syslog", "date", "own", "none") or closure
# showpid		whether to show pid after prefix in []
# handle		I/O glob or IO::Handle object
# no_ucfirst    don't capitalize first letter of message when no prefix
# no_prefixing  don't prefix logs
# no_newline	never append any newline character at the end of messages
#
# Other attributes:
#
# crlf          the new-line marker for this OS ("\n" on UNIX)
#
sub make {
	my $self = bless {}, shift;
	my (%args) = @_;

	my %set = (
		-prefix			=> \$self->{'prefix'},
		-stampfmt		=> \$self->{'stampfmt'},
		-showpid		=> \$self->{'showpid'},
		-handle			=> \$self->{'handle'},
		-no_ucfirst		=> \$self->{'no_ucfirst'},
		-no_prefixing	=> \$self->{'no_prefixing'},
		-no_newline		=> \$self->{'no_newline'},
	);

	while (my ($arg, $val) = each %args) {
		my $vset = $set{lc($arg)};
		unless (ref $vset) {
			require Carp;
			Carp::croak("Unknown switch $arg");
		}
		$$vset = $val;
	}

	#
	# Initialize proper time-stamping routine.
	#

	$self->{'stampfmt'} = stamping_fn($self->stampfmt)
		unless ref $self->stampfmt eq 'CODE';

	$self->{'crlf'} = $^O =~ /^dos|win/i ? "\r\n" : "\n";

	return $self;
}

#
# Local attribute access
#

sub handle			{ $_[0]->{'handle'} }

#
# ->write			-- defined
#
# Write logstring to the file.
# Priority is ignored by this channel.
#
sub write {
	my $self = shift;
	my ($priority, $logstring) = @_;

	#
	# This routine is called often...
	# Bypass the attribute access routines.
	#
	
	my $handle = $self->{handle};
	return unless defined $handle;

	my $prefix = '';
	$prefix = $self->prefixing_string(\$logstring)
		unless $self->{no_prefixing};

	my $crlf = '';
	$crlf = $self->{crlf} unless $self->{no_newline};

	print $handle join '', $prefix, $logstring, $crlf;

	return;
}

#
# ->close			-- defined
#
#
sub close {
	my $self = shift;
	$self->{handle} = undef;

	#
	# Do nothing on the handle itself.
	# We did not open the thing, we don't get to close it.
	#

	return;
}

1;	# for require
__END__