use Moo;
use Scalar::Util qw(blessed);
use Object::Remote::Logging::Logger;
+use Exporter::Declare;
+use Carp qw(carp croak);
extends 'Log::Contextual';
+exports(qw( ____ router arg_levels ));
+#exception log - log a message then die with that message
+export_tag elog => ('____');
+#fatal log - log a message then call exit(1)
+export_tag flog => ('____');
+
sub router {
our $Router_Instance ||= do {
require Object::Remote::Logging::Router;
}
}
+#log level descriptions
+#info - standard log level - normal program output for the end user
+#warn - output for program that is executing quietly
+#error - output for program that is running more quietly
+#fatal - it is not possible to continue execution; this level is as quiet as is possible
+#verbose - output for program executing verbosely (-v)
+#debug - output for program running more verbosely (-v -v)
+#trace - output for program running extremely verbosely (-v -v -v)
sub arg_levels {
- return [qw( trace debug verbose info warn error )];
+ #the order of the log levels is significant with the
+ #most verbose level being first in the list and the
+ #most quiet as the last item
+ return [qw( trace debug verbose info warn error fatal )];
+}
+
+sub before_import {
+ my ($class, $importer, $spec) = @_;
+ my $router = $class->router;
+
+ $class->SUPER::before_import($importer, $spec);
+
+ my @levels = @{$class->arg_levels($spec->config->{levels})};
+ for my $level (@levels) {
+ if ($spec->config->{elog}) {
+ $spec->add_export("&Elog_$level", sub (&) {
+ my ($code, @args) = @_;
+ $router->handle_log_request({
+ controller => $class,
+ package => scalar(caller),
+ caller_level => 1,
+ level => $level,
+ }, $code);
+ #TODO this should get fed into a logger so it can be formatted
+ croak $code->();
+ });
+ }
+ if ($spec->config->{flog}) {
+ #TODO that prototype isn't right
+ $spec->add_export("&Flog_$level", sub (&@) {
+ my ($code, $exit_value) = @_;
+ $exit_value = 1 unless defined $exit_value;
+ $router->handle_log_request({
+ controller => $class,
+ package => scalar(caller),
+ caller_level => 1,
+ level => $level,
+ }, $code);
+ #TODO this should get fed into a logger so it can be formatted
+ #don't let it going wrong stop us from calling exit()
+ eval { carp $code->() };
+ exit($exit_value);
+ });
+ }
+ }
}
#this is invoked on all nodes
sub init_logging {
my $level = $ENV{OBJECT_REMOTE_LOG_LEVEL};
+ my $format = $ENV{OBJECT_REMOTE_LOG_FORMAT};
+ #TODO allow the selections value to be * so it selects everything
+ my $selections = $ENV{OBJECT_REMOTE_LOG_SELECTIONS};
+ my %controller_should_log;
+
return unless defined $level;
+ $format = "[%l %r] %s" unless defined $format;
+ $selections = __PACKAGE__ unless defined $selections;
+ %controller_should_log = map { $_ => 1 } split(' ', $selections);
+
my $logger = Object::Remote::Logging::Logger->new(
- min_level => lc($level),
+ min_level => lc($level), format => $format,
level_names => Object::Remote::Logging::arg_levels(),
);
- #TODO check on speed of string compare against a hash with a single key
router()->connect(sub {
- return unless $_[1]->{controller} eq __PACKAGE__;
+ my $controller = $_[1]->{controller};
+ return unless $controller_should_log{'*'} || $controller_should_log{$controller};
#skip things from remote hosts because they log to STDERR
#when OBJECT_REMOTE_LOG_LEVEL is in effect
return if $_[1]->{remote}->{connection_id};
my ($self, %controller_info) = @_;
router()->_remote_metadata({ connection_id => $controller_info{connection_id} });
- router()->_forward_destination($controller_info{router});
+ router()->_forward_destination($controller_info{router}) if $ENV{OBJECT_REMOTE_LOG_FORWARDING};
}
1;
+__END__
+
+=head1 NAME
+
+Object::Remote::Logging - Logging subsystem for Object::Remote
+
+=head1 SYNOPSIS
+
+ use Object::Remote::Logging qw( :log :dlog :elog :flog arg_levels router );
+
+ @levels = qw( trace debug verbose info warn error fatal );
+ @levels = arg_levels(); #same result
+
+ $ENV{OBJECT_REMOTE_LOG_LEVEL} = 'trace'; #or other level name
+ $ENV{OBJECT_REMOTE_LOG_FORMAT} = '%l %t: %p::%m %s'; #and more
+ $ENV{OBJECT_REMOTE_LOG_FORWARDING} = 0 || 1; #default 0
+ $ENV{OBJECT_REMOTE_LOG_SELECTIONS} = 'Object::Remote::Logging Some::Other::Subclass';
+
+ log_info { 'Trace log event' };
+ Dlog_verbose { "Debug event with Data::Dumper::Concise: $_" } { foo => 'bar' };
+ Elog_error { 'Error event that calls die() with this string' };
+ Flog_fatal { 'Fatal event calls warn() then exit()' } 1;
+
+=head1 DESCRIPTION
+
+This is the logging framework for Object::Remote implemented as a subclass of
+L<Log::Contextual> with a slightly incompatible API. This system allows
+developers using Object::Remote and end users of that software to control
+Object::Remote logging so operation can be tracked if needed. This is also
+the API used to generate log messages inside the Object::Remote source code.
+
+The rest of the logging system comes from L<Object::Remote::Logging::Logger>
+which implements log rendering and output and L<Object::Remote::Logging::Router>
+which delivers log events to the loggers.
+
+=head1 EXPORTABLE SUBROUTINES
+
+=over 4
+
+=item arg_levels
+
+Returns an array reference that contains the ordered list of level names
+with the lowest log level first and the highest log level last.
+
+=item router
+
+Returns the instance of L<Object::Remote::Logging::Router> that is in use. The router
+instance is used in combination with L<Object::Remote::Logging::Logger> objects to
+select then render and output log messages.
+
+=item log_<level> and Dlog_<level>
+
+These methods come direct from L<Log::Contextual>; see that documentation for a
+complete reference. For each of the log level names there are subroutines with the log_
+and Dlog_ prefix that will generate the log message. The first argument is a code block
+that returns the log message contents and the optional further arguments are both passed
+to the block as the argument list and returned from the log method as a list.
+
+ log_trace { "A fine log message $_[0] " } 'if I do say so myself';
+ $hashref = Dlog_trace { "Very handy: $_" } { foo => 'bar' };
+
+=item logS_<level> and DlogS_<level>
+
+Works just like log_ and Dlog_ except returns only the first argument as a scalar value.
+
+ my $beverage = log_info { "Customer ordered $_[0]" } 'Coffee';
+
+=item Elog_<level>
+
+Log an event and then generate an exception by calling die() with the log message.
+
+ Elog_error { "Could not open file: $!" };
+
+=item Flog_<level>
+
+Log the event, generate a warning with the log message, then call exit(). The exit
+value will default to 1 or can be specified as an argument.
+
+ Flog_fatal { 'Could not lock resource' } 3;
+
+=back
+
+=head1 LEVEL NAMES
+
+Object::Remote uses an ordered list of log level names with the minimum level
+first and the maximum level last. The list of level names can be accessed via
+the arg_levels method which is exportable to the consumer of this class. The log
+level names are:
+
+=over 4
+
+=item trace
+
+As much information about operation as possible including multiple line dumps of
+large content. Tripple verbose operation (-v -v -v).
+
+=item debug
+
+Messages about operations that could hang as well as internal state changes,
+results from method invocations, and information useful when looking for faults.
+Double verbose operation (-v -v).
+
+=item verbose
+
+Additional optional messages to the user that can be enabled at their will. Single
+verbose operation (-v).
+
+=item info
+
+Messages from normal operation that are intended to be displayed to the end
+user if quiet operation is not indicated and more verbose operation is not
+in effect.
+
+=item warn
+
+Something wasn't supposed to happen but did. Operation was not impacted but
+otherwise the event is noteworthy. Single quiet operation (-q).
+
+=item error
+
+Something went wrong. Operation of the system may continue but some operation
+has most definitely failed. Double quiet operation (-q -q).
+
+=item fatal
+
+Something went wrong and recovery is not possible. The system should stop operating
+as soon as possible. Tripple quiet operation (-q -q -q).
+
+=back
+
+=head1 ENVIRONMENT
+
+=over 4
+
+=item OBJECT_REMOTE_LOG_LEVEL
+
+By default Object::Remote will generate log events but messages will not be
+output to STDERR. If there is a defined value for this variable then logs will
+be sent to STDERR if they are at this level or higher.
+
+=item OBJECT_REMOTE_LOG_FORMAT
+
+If logging output is enabled and this value is defined then the logger will
+use this format string instead of the default '[%l %r] %s'; See
+L<Object::Remote::Logging::Logger> for documentation on the format string.
+
+=item OBJECT_REMOTE_LOG_SELECTIONS
+
+By default Object::Remote log output will only be enabled for messages generated inside
+Object::Remote packages. If logs should be generated for other log messages instead of just
+Object::Remote messages set this variable to the names of any Object::Remote::Logging subclass or
+Object::Remote::Logging itself seperated by a space. To output all logs generated set the value
+to *.
+
+=item OBJECT_REMOTE_LOG_FORWARDING
+
+Object::Remote can forward log events from the remote Perl interpreter to the local Perl
+interpreter in a transparent way. Currently this feature is disabled by default but
+that will change Really Soon Now(TM); to enable it set the variable to '1'.
+
+=back