AnyEvent-MP/MP/LogCatcher.pm

=head1 NAME

AnyEvent::MP::LogCatcher - catch all logs from all nodes

=head1 SYNOPSIS

   use AnyEvent::MP::LogCatcher;

=head1 DESCRIPTION

This relatively simple module attaches itself to the
C<$AnyEvent::Log::COLLECT> context on every node and sends all log
messages to the node showing interest via the C<catch> function.

No attempt to buffer log messages on connection loss, or to retransmit
lost messages, is done.

=head1 GLOBALS AND FUNCTIONS

=over 4

=cut

package AnyEvent::MP::LogCatcher;

use common::sense;
use Carp ();
use POSIX ();

use AnyEvent ();
use AnyEvent::Log ();
use AnyEvent::Util ();

use AnyEvent::MP;
use AnyEvent::MP::Kernel;

use base "Exporter";

AE::log 7 => "starting log catcher service.";

our $LOGLEVEL;
our %lport; # local logging ports

# other nodes connect via this
sub connect {
   my ($version, $rport, $loglevel) = @_;

   my $ctx = new AnyEvent::Log::Ctx
      title  => "AnyEvent::MP::LogCatcher",
      level  => $loglevel,
      log_cb => sub {
         snd $rport, @{ $_[0] };
      },
      fmt_cb => sub {
         [$_[0], $_[1]->title, $_[2], $_[3]]
      },
   ;

   $AnyEvent::Log::COLLECT->attach ($ctx);

   # monitor them, silently die
   mon $rport, sub {
      $AnyEvent::Log::COLLECT->detach ($ctx);
   };
}

sub mon_node {
   my ($node, $is_up) = @_;

   return unless $is_up;

   my $lport = $lport{$node} = port {
      my ($time, $ctx, $level, $msg) = @_;

      $level = 2 if $level < 2; # do not exit because others do so

      my $diff = $time - AE::now;
      $diff = $diff < 1e-4 ? "" : sprintf ", %gs", $diff;
      AE::log $level, "[$node$diff] $msg";
   };

   # establish connection
   AnyEvent::MP::Kernel::snd_to_func $node, "AnyEvent::MP::LogCatcher::connect", 0, $lport, $LOGLEVEL;

   mon $node, $lport;
}

=item AnyEvent::MP::LogCatcher::catch [$level]

Starts catching all log messages from all nodes with level C<$level> or
lower. If the C<$level> is C<undef>, then stop catching all messages
again.

Example: start a node that catches all messages (you might have to specify
a suitable profile name).

   aemp run profilename services '[["AnyEvent::MP::LogCatcher::catch",9]]'

=cut

sub catch {
   $LOGLEVEL = $_[0];
   kil $_, "restart" for values %lport;
   %lport = ();

   return unless defined $LOGLEVEL;

   mon_node $_, 1
      for up_nodes;

   mon_nodes \&mon_node;
   ()
}

=back

=head1 SEE ALSO

L<AnyEvent::MP>.

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

=cut

1

Revision:	1.5
Committed:	Thu Mar 22 01:24:26 2012 UTC (12 years, 2 months ago) by root
Branch:	MAIN
Changes since 1.4:	+24 -18 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3			AnyEvent::MP::LogCatcher - catch all logs from all nodes
4
5			=head1 SYNOPSIS
6
7			use AnyEvent::MP::LogCatcher;
8
9			=head1 DESCRIPTION
10
11	root	1.5	This relatively simple module attaches itself to the
12			C<$AnyEvent::Log::COLLECT> context on every node and sends all log
13			messages to the node showing interest via the C<catch> function.
14	root	1.1
15	root	1.5	No attempt to buffer log messages on connection loss, or to retransmit
16			lost messages, is done.
17	root	1.1
18			=head1 GLOBALS AND FUNCTIONS
19
20			=over 4
21
22			=cut
23
24			package AnyEvent::MP::LogCatcher;
25
26			use common::sense;
27			use Carp ();
28			use POSIX ();
29
30			use AnyEvent ();
31	root	1.5	use AnyEvent::Log ();
32	root	1.1	use AnyEvent::Util ();
33
34			use AnyEvent::MP;
35			use AnyEvent::MP::Kernel;
36
37			use base "Exporter";
38
39	root	1.5	AE::log 7 => "starting log catcher service.";
40	root	1.1
41			our $LOGLEVEL;
42			our %lport; # local logging ports
43
44			# other nodes connect via this
45			sub connect {
46			my ($version, $rport, $loglevel) = @_;
47
48	root	1.5	my $ctx = new AnyEvent::Log::Ctx
49			title => "AnyEvent::MP::LogCatcher",
50			level => $loglevel,
51			log_cb => sub {
52			snd $rport, @{ $_[0] };
53			},
54			fmt_cb => sub {
55			[$_[0], $_[1]->title, $_[2], $_[3]]
56			},
57			;
58	root	1.1
59	root	1.5	$AnyEvent::Log::COLLECT->attach ($ctx);
60	root	1.1
61			# monitor them, silently die
62			mon $rport, sub {
63	root	1.5	$AnyEvent::Log::COLLECT->detach ($ctx);
64	root	1.1	};
65			}
66
67			sub mon_node {
68			my ($node, $is_up) = @_;
69
70			return unless $is_up;
71
72			my $lport = $lport{$node} = port {
73	root	1.5	my ($time, $ctx, $level, $msg) = @_;
74	root	1.1
75	root	1.5	$level = 2 if $level < 2; # do not exit because others do so
76	root	1.1
77	root	1.5	my $diff = $time - AE::now;
78			$diff = $diff < 1e-4 ? "" : sprintf ", %gs", $diff;
79			AE::log $level, "[$node$diff] $msg";
80	root	1.1	};
81
82			# establish connection
83	root	1.4	AnyEvent::MP::Kernel::snd_to_func $node, "AnyEvent::MP::LogCatcher::connect", 0, $lport, $LOGLEVEL;
84	root	1.1
85	root	1.4	mon $node, $lport;
86	root	1.1	}
87
88	root	1.3	=item AnyEvent::MP::LogCatcher::catch [$level]
89
90			Starts catching all log messages from all nodes with level C<$level> or
91			lower. If the C<$level> is C<undef>, then stop catching all messages
92			again.
93
94			Example: start a node that catches all messages (you might have to specify
95			a suitable profile name).
96
97			aemp run profilename services '[["AnyEvent::MP::LogCatcher::catch",9]]'
98
99			=cut
100
101	root	1.1	sub catch {
102			$LOGLEVEL = $_[0];
103			kil $_, "restart" for values %lport;
104			%lport = ();
105
106			return unless defined $LOGLEVEL;
107
108			mon_node $_, 1
109			for up_nodes;
110
111			mon_nodes \&mon_node;
112			()
113			}
114
115			=back
116
117			=head1 SEE ALSO
118
119			L<AnyEvent::MP>.
120
121			=head1 AUTHOR
122
123			Marc Lehmann <schmorp@schmorp.de>
124			http://home.schmorp.de/
125
126			=cut
127
128			1
129