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=head1 NAME |
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|
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AnyEvent::MP::LogCatcher - catch all logs from all nodes |
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|
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=head1 SYNOPSIS |
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|
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use AnyEvent::MP::LogCatcher; |
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|
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=head1 DESCRIPTION |
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|
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This relatively simple module attaches itself to the |
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C<$AnyEvent::Log::COLLECT> context on every node and sends all log |
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messages to the node showing interest via the C<catch> function. |
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|
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No attempt to buffer log messages on connection loss, or to retransmit |
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lost messages, is done. |
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|
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=head1 GLOBALS AND FUNCTIONS |
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|
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=over 4 |
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|
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=cut |
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|
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package AnyEvent::MP::LogCatcher; |
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|
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use common::sense; |
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use Carp (); |
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use POSIX (); |
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|
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use AnyEvent (); |
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use AnyEvent::Log (); |
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use AnyEvent::Util (); |
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|
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use AnyEvent::MP; |
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use AnyEvent::MP::Kernel; |
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|
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use base "Exporter"; |
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|
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AE::log 7 => "starting log catcher service."; |
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|
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our $LOGLEVEL; |
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our $MON; |
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our $PROPAGATE = 1; # set to one when messages ought to be send to remote nodes |
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our %lport; # local logging ports |
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|
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# other nodes connect via this |
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sub connect { |
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my ($version, $rport, $loglevel) = @_; |
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|
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# context to catch log messages |
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my $ctx = new AnyEvent::Log::Ctx |
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title => "AnyEvent::MP::LogCatcher", |
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level => $loglevel, |
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log_cb => sub { |
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snd $rport, @{ $_[0] } |
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if $PROPAGATE; |
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}, |
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fmt_cb => sub { |
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[$_[0], $_[1]->title, $_[2], $_[3]] |
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}, |
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; |
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|
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$AnyEvent::Log::COLLECT->attach ($ctx); |
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|
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# monitor them, silently die if they die |
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mon $rport, sub { |
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$AnyEvent::Log::COLLECT->detach ($ctx); |
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}; |
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|
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AE::log 8 => "starting to propagate log messages to $rport"; |
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} |
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|
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sub mon_node { |
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my ($node) = @_; |
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|
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# don't log messages from ourselves |
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return if $node eq $NODE; |
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|
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$lport{$node} ||= do { |
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my $lport = port { |
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my ($time, $ctx, $level, $msg) = @_; |
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|
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$level = 2 if $level < 2; # do not exit just because others do so |
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|
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my $diff = AE::now - $time; |
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$diff = (abs $diff) < 1e-3 ? "" : sprintf "%+.3fs", $diff; |
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|
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local $PROPAGATE; # do not propagate to other nodes |
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(AnyEvent::Log::ctx $ctx)->log ($level, "[$node$diff] $msg"); |
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}; |
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|
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mon $lport, sub { |
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delete $lport{$node} |
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or return; |
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AE::log error => "@_" |
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if @_; |
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mon_node ($node); |
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}; |
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|
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# establish connection |
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AnyEvent::MP::Kernel::snd_to_func $node, "AnyEvent::MP::LogCatcher::connect", 0, $lport, $LOGLEVEL; |
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|
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mon $node, $lport; |
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|
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$lport |
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} |
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} |
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=item AnyEvent::MP::LogCatcher::catch [$level] |
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Starts catching all log messages from all nodes with level C<$level> or |
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lower. If the C<$level> is C<undef>, then stop catching all messages |
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again. |
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|
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Example: start a node that catches all messages (you might have to specify |
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a suitable profile name). |
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|
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AE_VERBOSE=9 aemp run profilename services '[["AnyEvent::MP::LogCatcher::catch",9]]' |
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|
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=cut |
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|
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sub catch { |
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$LOGLEVEL = $_[0]; |
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kil $_ for values %lport; |
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%lport = (); |
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return unless defined $LOGLEVEL; |
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|
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$MON = db_mon "'l" => sub { |
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my ($family, $add, $chg, $del) = @_; |
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|
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kil delete $lport{$_} |
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for @$del; |
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|
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mon_node $_ |
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for @$add; |
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}; |
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|
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() |
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} |
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|
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=back |
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|
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=head1 LOGGING |
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AnyEvent::MP::LogCatcher logs messages from remote nodes. It logs them |
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into the original logging context and prepends the origin node name |
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and, if the time difference is larger than 1e-4 seconds, also the time |
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difference between local time and origin time. |
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=head1 SEE ALSO |
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|
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L<AnyEvent::MP>. |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <schmorp@schmorp.de> |
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http://home.schmorp.de/ |
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|
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=cut |
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|
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1 |
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