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package Catalyst::Log;
use Moose;
use Moose::Util 'find_meta';
use Carp qw/ cluck /;
our %LEVELS = (); # Levels stored as bit field, ergo debug = 1, warn = 2 etc
our %LEVEL_MATCH = (); # Stored as additive, thus debug = 31, warn = 30 etc
has level => (is => 'rw');
has _body => (is => 'rw');
has abort => (is => 'rw');
has autoflush => (is => 'rw', default => sub {1});
has _psgi_logger => (is => 'rw', predicate => '_has_psgi_logger', clearer => '_clear_psgi_logger');
has _psgi_errors => (is => 'rw', predicate => '_has_psgi_errors', clearer => '_clear_psgi_errors');
sub clear_psgi {
my $self = shift;
$self->_clear_psgi_logger;
$self->_clear_psgi_errors;
}
sub psgienv {
my ($self, $env) = @_;
$self->_psgi_logger($env->{'psgix.logger'}) if $env->{'psgix.logger'};
$self->_psgi_errors($env->{'psgi.errors'}) if $env->{'psgi.errors'};
}
{
my @levels = qw[ debug info warn error fatal ];
my $meta = find_meta(__PACKAGE__);
my $summed_level = 0;
for ( my $i = $#levels ; $i >= 0 ; $i-- ) {
my $name = $levels[$i];
my $level = 1 << $i;
$summed_level |= $level;
$LEVELS{$name} = $level;
$LEVEL_MATCH{$name} = $summed_level;
$meta->add_method($name, sub {
my $self = shift;
if ( $self->level & $level ) {
$self->_log( $name, @_ );
}
});
$meta->add_method("is_$name", sub {
my $self = shift;
return $self->level & $level;
});;
}
}
around new => sub {
my $orig = shift;
my $class = shift;
my $self = $class->$orig;
$self->levels( scalar(@_) ? @_ : keys %LEVELS );
return $self;
};
sub levels {
my ( $self, @levels ) = @_;
$self->level(0);
$self->enable(@levels);
}
sub enable {
my ( $self, @levels ) = @_;
my $level = $self->level;
for(map { $LEVEL_MATCH{$_} } @levels){
$level |= $_;
}
$self->level($level);
}
sub disable {
my ( $self, @levels ) = @_;
my $level = $self->level;
for(map { $LEVELS{$_} } @levels){
$level &= ~$_;
}
$self->level($level);
}
our $HAS_DUMPED;
sub _dump {
my $self = shift;
unless ($HAS_DUMPED++) {
cluck("Catalyst::Log::_dump is deprecated and will be removed. Please change to using your own Dumper.\n");
}
$self->info( Data::Dump::dump(@_) );
}
sub _log {
my $self = shift;
my $level = shift;
my $message = join( "\n", @_ );
if ($self->can('_has_psgi_logger') and $self->_has_psgi_logger) {
$self->_psgi_logger->({
level => $level,
message => $message,
});
} else {
$message .= "\n" unless $message =~ /\n$/;
my $body = $self->_body;
$body .= sprintf( "[%s] %s", $level, $message );
$self->_body($body);
}
if( $self->autoflush && !$self->abort ) {
$self->_flush;
}
return 1;
}
sub _flush {
my $self = shift;
if ( $self->abort || !$self->_body ) {
$self->abort(undef);
}
else {
$self->_send_to_log( $self->_body );
}
$self->_body(undef);
}
sub _send_to_log {
my $self = shift;
if ($self->can('_has_psgi_errors') and $self->_has_psgi_errors) {
$self->_psgi_errors->print(@_);
} else {
binmode STDERR, ":utf8";
print STDERR @_;
}
}
# 5.7 compat code.
# Alias _body to body, add a before modifier to warn..
my $meta = __PACKAGE__->meta; # Calling meta method here fine as we happen at compile time.
$meta->add_method('body', $meta->get_method('_body'));
my %package_hash; # Only warn once per method, per package.
# I haven't provided a way to disable them, patches welcome.
$meta->add_before_method_modifier('body', sub {
my $class = blessed(shift);
$package_hash{$class}++ || do {
warn("Class $class is calling the deprecated method Catalyst::Log->body method,\n"
. "this will be removed in Catalyst 5.81");
};
});
# End 5.70 backwards compatibility hacks.
no Moose;
__PACKAGE__->meta->make_immutable(inline_constructor => 0);
1;
__END__
=for stopwords psgienv
=head1 NAME
Catalyst::Log - Catalyst Log Class
=head1 SYNOPSIS
$log = $c->log;
$log->debug($message);
$log->info($message);
$log->warn($message);
$log->error($message);
$log->fatal($message);
if ( $log->is_debug ) {
# expensive debugging
}
See L<Catalyst>.
=head1 DESCRIPTION
This module provides the default, simple logging functionality for Catalyst.
If you want something different set C<< $c->log >> in your application module,
e.g.:
$c->log( MyLogger->new );
Your logging object is expected to provide the interface described here.
Good alternatives to consider are Log::Log4Perl and Log::Dispatch.
If you want to be able to log arbitrary warnings, you can do something along
the lines of
$SIG{__WARN__} = sub { MyApp->log->warn(@_); };
however this is (a) global, (b) hairy and (c) may have unexpected side effects.
Don't say we didn't warn you.
=head1 LOG LEVELS
=head2 debug
$log->is_debug;
$log->debug($message);
=head2 info
$log->is_info;
$log->info($message);
=head2 warn
$log->is_warn;
$log->warn($message);
=head2 error
$log->is_error;
$log->error($message);
=head2 fatal
$log->is_fatal;
$log->fatal($message);
=head1 METHODS
=head2 new
Constructor. Defaults to enable all levels unless levels are provided in
arguments.
$log = Catalyst::Log->new;
$log = Catalyst::Log->new( 'warn', 'error' );
=head2 level
Contains a bitmask of the currently set log levels.
=head2 levels
Set log levels
$log->levels( 'warn', 'error', 'fatal' );
=head2 enable
Enable log levels
$log->enable( 'warn', 'error' );
=head2 disable
Disable log levels
$log->disable( 'warn', 'error' );
=head2 is_debug
=head2 is_error
=head2 is_fatal
=head2 is_info
=head2 is_warn
Is the log level active?
=head2 abort
Should Catalyst emit logs for this request? Will be reset at the end of
each request.
*NOTE* This method is not compatible with other log apis, so if you plan
to use Log4Perl or another logger, you should call it like this:
$c->log->abort(1) if $c->log->can('abort');
=head2 autoflush
When enabled (default), messages are written to the log immediately instead
of queued until the end of the request.
This option, as well as C<abort>, is provided for modules such as
L<Catalyst::Plugin::Static::Simple> to be able to programmatically
suppress the output of log messages. By turning off C<autoflush> (application-wide
setting) and then setting the C<abort> flag within a given request, all log
messages for the given request will be suppressed. C<abort> can still be set
independently of turning off C<autoflush>, however. It just means any messages
sent to the log up until that point in the request will obviously still be emitted,
since C<autoflush> means they are written in real-time.
If you need to turn off autoflush you should do it like this (in your main app
class):
after setup_finalize => sub {
my $c = shift;
$c->log->autoflush(0) if $c->log->can('autoflush');
};
=head2 _send_to_log
$log->_send_to_log( @messages );
This protected method is what actually sends the log information to STDERR.
You may subclass this module and override this method to get finer control
over the log output.
=head2 psgienv $env
$log->psgienv($env);
NOTE: This is not meant for public consumption.
Set the PSGI environment for this request. This ensures logs will be sent to
the right place. If the environment has a C<psgix.logger>, it will be used. If
not, we will send logs to C<psgi.errors> if that exists. As a last fallback, we
will send to STDERR as before.
=head2 clear_psgi
Clears the PSGI environment attributes set by L</psgienv>.
=head2 meta
=head1 SEE ALSO
L<Catalyst>.
=head1 AUTHORS
Catalyst Contributors, see Catalyst.pm
=head1 COPYRIGHT
This library is free software. You can redistribute it and/or modify
it under the same terms as Perl itself.
=cut
__PACKAGE__->meta->make_immutable;
1;