NAME

Fluent::Logger - A structured event logger for Fluent

SYNOPSIS

use Fluent::Logger;

my $logger = Fluent::Logger->new(
    host => '127.0.0.1',
    port => 24224,
);
$logger->post("myapp.access", { "agent" => "foo" });
# output: myapp.access {"agent":"foo"}

my $logger = Fluent::Logger->new(
    tag_prefix => 'myapp',
    host       => '127.0.0.1',
    port       => 24224,
);
$logger->post("access", { "agent" => "foo" });
# output: myapp.access {"agent":"foo"}

DESCRIPTION

Fluent::Logger is a structured event logger for Fluentd.

METHODS

• new(%args)

  create new logger instance.

  %args:

    tag_prefix                  => 'Str':  optional
    host                        => 'Str':  default is '127.0.0.1'
    port                        => 'Int':  default is 24224
    timeout                     => 'Num':  default is 3.0
    socket                      => 'Str':  default undef (e.g. "/var/run/fluent/fluent.sock")
    prefer_integer              => 'Bool': default 1 (set to Data::MessagePack->prefer_integer)
    event_time                  => 'Bool': default 0 (timestamp includes nanoseconds, supported by fluentd >= 0.14.0)
    buffer_limit                => 'Int':  defualt 8388608 (8MB)
    buffer_overflow_handler     => 'Code': optional
    truncate_buffer_at_overflow => 'Bool': default 0
    ack                         => 'Bool': default 0 (not works on MSWin32)
    retry_immediately           => 'Int':  default 0 (retries immediately  N times on error occured)
  

  • buffer_overflow_handler

    You can inject your own custom coderef to handle buffer overflow in the event of connection failure. This will mitigate the loss of data instead of simply throwing data away.

    Your proc should accept a single argument, which will be the internal buffer of messages from the logger. This coderef is also called when logger.close() failed to flush the remaining internal buffer of messages. A typical use-case for this would be writing to disk or possibly writing to Redis.

  • truncate_buffer_at_overflow

    When truncate_buffer_at_overflow is true and pending buffer size is larger than buffer_limit, post() returns undef.

    Pending buffer still be kept, but last message passed to post() is not sent and not appended to buffer. You may handle the message by other method.

  • ack

    post() waits ack response from server for each messages.

    An exception will raise if ack is miss match or timed out.

    This option does not work on MSWin32 platform currently, because Data::MessagePack::Stream does not work.

  • retry_immediately

    By default, Fluent::Logger will retry to send the buffer at next post() called when an error occured in post().

    If retry_immediately(N) is set, retries immediately max N times.

• post($tag:Str, $msg:HashRef)

  Send message to fluent server with tag.

  Return bytes length of written messages.

  If event_time is set to true, log's timestamp includes nanoseconds.

• post_with_time($tag:Str, $msg:HashRef, $time:Int|Float)

  Send message to fluent server with tag and time.

  If event_time is set to true, $time argument accepts Float value (such as Time::HiRes::time()).

• close()

  close connection.

  If the logger has pending data, flushing it to server on close.

• errstr

  return error message.

    $logger->post( info => { "msg": "test" } )
        or die $logger->errstr;
  

AUTHOR

HIROSE Masaaki <hirose31 _at_ gmail.com>

Shinichiro Sei <sei _at_ kayac.com>

FUJIWARA Shunichiro <fujiwara _at_ cpan.org>

THANKS TO

Kazuki Ohta

FURUHASHI Sadayuki

lestrrat

REPOSITORY

https://github.com/fluent/fluent-logger-perl

git clone git://github.com/fluent/fluent-logger-perl.git

patches and collaborators are welcome.

SEE ALSO

http://fluent.github.com/

COPYRIGHT & LICENSE

Copyright FUJIWARA Shunichiro

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.