package Catmandu::Logger;
use Catmandu::Sane;
our $VERSION = '1.0306';
use Moo::Role;
use Log::Any ();
use namespace::clean;
has log => (is => 'lazy', init_arg => undef);
has log_category => (is => 'lazy');
{
my $loggers = {};
sub _build_log {
my ($self) = @_;
my $category = $self->log_category;
$loggers->{$category} ||= Log::Any->get_logger(category => $category);
}
}
sub _build_log_category {
ref $_[0];
}
1;
__END__
=pod
=head1 NAME
Catmandu::Logger - A role for classes that need logging capabilities
=head1 SYNOPSIS
package MyApp::View;
use Moo;
with 'Catmandu::Logger';
sub something {
my ($self) = @_;
$self->log->debug("started bar"); # logs with default class catergory "MyApp::View"
$self->log->error("started bar");
}
=head1 DESCRIPTION
A logging role building a very lightweight wrapper to L<Log::Any>. Connecting
a Log::Any::Adapter should be performed prior to logging the first log message,
otherwise nothing will happen, just like with Log::Any.
The logger needs to be setup before using the logger, which could happen in the main application:
package main;
use Log::Any::Adapter;
use Log::Log4perl;
Log::Any::Adapter->set('Log4perl');
Log::Log4perl::init('./log4perl.conf');
my $app = MyApp::View->new;
$app->something(); # will print debug and error messages
with log4perl.conf like:
log4perl.rootLogger=DEBUG,OUT
log4perl.appender.OUT=Log::Log4perl::Appender::Screen
log4perl.appender.OUT.stderr=1
log4perl.appender.OUT.utf8=1
log4perl.appender.OUT.layout=PatternLayout
log4perl.appender.OUT.layout.ConversionPattern=%d [%P] - %p %l time=%r : %m%n
See L<Log::Log4perl> for more configuration options and selecting which messages
to log and which not.
=head1 CATMANDU COMMAND LINE
When using the L<catmandu> command line, the logger can be activated using the
-D option on all Catmandu commands:
$ catmandu -D convert JSON to YAML < data.json
$ catmandu -D export MongoDB --database-name items --bag
The log4perl configuration for the C<catmandu> command line must be defined in a
'catmandu.yml' configuration file:
$ cat catmandu.yml
log4perl: |
log4perl.rootLogger=DEBUG,OUT
log4perl.appender.OUT=Log::Log4perl::Appender::Screen
log4perl.appender.OUT.stderr=1
log4perl.appender.OUT.utf8=1
log4perl.appender.OUT.layout=PatternLayout
log4perl.appender.OUT.layout.ConversionPattern=%d [%P] - %p %l time=%r : %m%n
The C<log4perl> section can point to an inline log4perl configuration or a
filename containing the configuration.
See L<Catmandu::Fix::log> how to include log messages in the L<Catmandu::Fix>
language.
=head1 ACCESSORS
=head2 log
The C<log> attribute holds the L<Log::Any::Adapter> object that implements all
logging methods for the defined log levels, such as C<debug> or C<error>.
package MyApp::View::JSON;
extends 'MyApp::View';
with 'Catmandu::Logger';
sub bar {
$self->log->info("Everything fine so far"); # logs a info message
$self->log->debug("Something is fishy here"); # logs a debug message
}
Your package automatically has a logging category of MyApp::View::JSON. Use lines like:
log4perl.logger.MyApp::View::JSON=DEBUG,STDOUT
or
log4perl.logger.MyApp::View=DEBUG,STDOUT
or
log4perl.logger.MyApp=DEBUG,STDOUT
for specialized logging for your application.
=head2 log_category
Default is the class name.
=head1 SEE ALSO
L<Log::Any>
=cut