X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=scpubgit%2FObject-Remote.git;a=blobdiff_plain;f=lib%2FObject%2FRemote%2FLogging.pm;h=48110480e220db8025696281164d7a3efcef95d3;hp=22860ed2bb61e4b810569dcfc92a305ffbaa9f50;hb=d672a9bff87112bf8cfea0a5749e934d4c8c996e;hpb=0fe333eb337345ecc842a14bf738b5db837936b0

diff --git a/lib/Object/Remote/Logging.pm b/lib/Object/Remote/Logging.pm
index 22860ed..4811048 100644
--- a/lib/Object/Remote/Logging.pm
+++ b/lib/Object/Remote/Logging.pm
@@ -4,10 +4,15 @@ 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 ));
+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 {
@@ -31,20 +36,68 @@ sub arg_levels {
   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), 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 $_[1]->{remote}->{connection_id};
@@ -58,8 +111,169 @@ sub init_logging_forwarding {
   my ($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