.\" -*- mode: troff; coding: utf-8 -*- .\" Automatically generated by Pod::Man v6.0.2 (Pod::Simple 3.45) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. .ie n \{\ . ds C` "" . ds C' "" 'br\} .el\{\ . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" .\" Required to disable full justification in groff 1.23.0. .if n .ds AD l .\" ======================================================================== .\" .IX Title "Appender::Limit 3" .TH Appender::Limit 3 2026-08-14 "perl v5.42.2" "User Contributed Perl Documentation" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH NAME Log::Log4perl::Appender::Limit \- Limit message delivery via block period .SH SYNOPSIS .IX Header "SYNOPSIS" .Vb 1 \& use Log::Log4perl qw(:easy); \& \& my $conf = qq( \& log4perl.category = WARN, Limiter \& \& # Email appender \& log4perl.appender.Mailer = Log::Dispatch::Email::MailSend \& log4perl.appender.Mailer.to = drone\e@pageme.com \& log4perl.appender.Mailer.subject = Something\*(Aqs broken! \& log4perl.appender.Mailer.buffered = 0 \& log4perl.appender.Mailer.layout = PatternLayout \& log4perl.appender.Mailer.layout.ConversionPattern=%d %m %n \& \& # Limiting appender, using the email appender above \& log4perl.appender.Limiter = Log::Log4perl::Appender::Limit \& log4perl.appender.Limiter.appender = Mailer \& log4perl.appender.Limiter.block_period = 3600 \& ); \& \& Log::Log4perl\->init(\e$conf); \& WARN("This message will be sent immediately."); \& WARN("This message will be delayed by one hour."); \& sleep(3601); \& WARN("This message plus the last one will be sent now, seperately."); .Ve .SH DESCRIPTION .IX Header "DESCRIPTION" .ie n .IP """appender""" 4 .el .IP \f(CWappender\fR 4 .IX Item "appender" Specifies the name of the appender used by the limiter. The appender specified must be defined somewhere in the configuration file, not necessarily before the definition of \&\f(CW\*(C`Log::Log4perl::Appender::Limit\*(C'\fR. .ie n .IP """block_period""" 4 .el .IP \f(CWblock_period\fR 4 .IX Item "block_period" Period in seconds between delivery of messages. If messages arrive in between, they will be either saved (if \f(CW\*(C`accumulate\*(C'\fR is set to a true value) or discarded (if \f(CW\*(C`accumulate\*(C'\fR isn\*(Aqt set). .ie n .IP """persistent""" 4 .el .IP \f(CWpersistent\fR 4 .IX Item "persistent" File name in which \f(CW\*(C`Log::Log4perl::Appender::Limit\*(C'\fR persistently stores delivery times. If omitted, the appender will have no recollection of what happened when the program restarts. .ie n .IP """max_until_flushed""" 4 .el .IP \f(CWmax_until_flushed\fR 4 .IX Item "max_until_flushed" Maximum number of accumulated messages. If exceeded, the appender flushes all messages, regardless if the interval set in \f(CW\*(C`block_period\*(C'\fR has passed or not. Don\*(Aqt mix with \f(CW\*(C`max_until_discarded\*(C'\fR. .ie n .IP """max_until_discarded""" 4 .el .IP \f(CWmax_until_discarded\fR 4 .IX Item "max_until_discarded" Maximum number of accumulated messages. If exceeded, the appender will simply discard additional messages, waiting for \f(CW\*(C`block_period\*(C'\fR to expire to flush all accumulated messages. Don\*(Aqt mix with \f(CW\*(C`max_until_flushed\*(C'\fR. .ie n .IP """appender_method_on_flush""" 4 .el .IP \f(CWappender_method_on_flush\fR 4 .IX Item "appender_method_on_flush" Optional method name to be called on the appender attached to the limiter when messages are flushed. For example, to have the sample code in the SYNOPSIS section bundle buffered emails into one, change the mailer\*(Aqs \f(CW\*(C`buffered\*(C'\fR parameter to \f(CW1\fR and set the limiters \&\f(CW\*(C`appender_method_on_flush\*(C'\fR value to the string \f(CW"flush"\fR: .Sp .Vb 1 \& log4perl.category = WARN, Limiter \& \& # Email appender \& log4perl.appender.Mailer = Log::Dispatch::Email::MailSend \& log4perl.appender.Mailer.to = drone\e@pageme.com \& log4perl.appender.Mailer.subject = Something\*(Aqs broken! \& log4perl.appender.Mailer.buffered = 1 \& log4perl.appender.Mailer.layout = PatternLayout \& log4perl.appender.Mailer.layout.ConversionPattern=%d %m %n \& \& # Limiting appender, using the email appender above \& log4perl.appender.Limiter = Log::Log4perl::Appender::Limit \& log4perl.appender.Limiter.appender = Mailer \& log4perl.appender.Limiter.block_period = 3600 \& log4perl.appender.Limiter.appender_method_on_flush = flush .Ve .Sp This will cause the mailer to buffer messages and wait for \f(CWflush()\fR to send out the whole batch. The limiter will then call the appender\*(Aqs \&\f(CWflush()\fR method when it\*(Aqs own buffer gets flushed out. .PP If the appender attached to \f(CW\*(C`Limit\*(C'\fR uses \f(CW\*(C`PatternLayout\*(C'\fR with a timestamp specifier, you will notice that the message timestamps are reflecting the original log event, not the time of the message rendering in the attached appender. Major trickery has been applied to accomplish this (Cough!). .SH "DEVELOPMENT NOTES" .IX Header "DEVELOPMENT NOTES" \&\f(CW\*(C`Log::Log4perl::Appender::Limit\*(C'\fR is a \fIcomposite\fR appender. Unlike other appenders, it doesn\*(Aqt log any messages, it just passes them on to its attached sub\-appender. For this reason, it doesn\*(Aqt need a layout (contrary to regular appenders). If it defines none, messages are passed on unaltered. .PP Custom filters are also applied to the composite appender only. They are \fInot\fR applied to the sub\-appender. Same applies to appender thresholds. This behaviour might change in the future. .SH LICENSE .IX Header "LICENSE" Copyright 2002\-2026 by Mike Schilli and Kevin Goess . .PP This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.