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Masahiro Nagano > Apache-LogFormat-Compiler-0.05 > Apache::LogFormat::Compiler



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Module Version: 0.04   Source   Latest Release: Apache-LogFormat-Compiler-0.35


Apache::LogFormat::Compiler - Compile LogFormat to perl-code


  use Apache::LogFormat::Compiler;

  my $log_handler = Apache::LogFormat::Compiler->new("combined");
  my $log = $log_handler->log_line(


Compile LogFormat to perl-code. For faster generating access_log line.



Takes a format string (or a preset template combined or custom) to specify the log format. This middleware implements a subset of Apache's LogFormat templates:

   %%    a percent sign
   %h    REMOTE_ADDR from the PSGI environment, or -
   %l    remote logname not implemented (currently always -)
   %u    REMOTE_USER from the PSGI environment, or -
   %t    [local timestamp, in default format]
   %r    REQUEST_METHOD, REQUEST_URI and SERVER_PROTOCOL from the PSGI environment
   %s    the HTTP status code of the response
   %b    content length of the response
   %T    custom field for handling times in subclasses
   %D    custom field for handling sub-second times in subclasses
   %v    SERVER_NAME from the PSGI environment, or -
   %V    HTTP_HOST or SERVER_NAME from the PSGI environment, or -
   %p    SERVER_PORT from the PSGI environment
   %P    the worker's process id
   %m    REQUEST_METHOD from the PSGI environment
   %U    PATH_INFO from the PSGI environment
   %q    QUERY_STRING from the PSGI environment
   %H    SERVER_PROTOCOL from the PSGI environment

Some of these format fields are only supported by middleware that subclasses AccessLog.

In addition, custom values can be referenced, using %{name}, with one of the mandatory modifier flags i, o or t:

   %{variable-name}i    HTTP_VARIABLE_NAME value from the PSGI environment
   %{header-name}o      header-name header in the response
   %{time-format]t      localtime in the specified strftime format
log_line($env:HashRef,$res:ArrayRef,$length:Integer,$reqtime:Integer,$time:Integer): $log:String

Generates log line.

  $env      PSGI-style $env
  $res      PSGI-style $res
  $length   Content-Length
  $reqtime  the time taken to serve request in microseconds 
  $time     time the request was received

Sample psgi

  use Plack::Builder;
  use Time::HiRes;
  use Apache::LogFormat::Compiler;

  my $log_handler = Apache::LogFormat::Compiler->new(
      '%h %l %u %t "%r" %>s %b "%{Referer}i" "%{User-agent}i" %D'
  my $compile_log_app = builder {
      enable sub {
          my $app = shift;
          sub {
              my $env = shift;
              my $t0 = [gettimeofday];
              my $res = $app->();
              my $reqtime = int(Time::HiRes::tv_interval($t0) * 1_000_000);
                  $env,$res,6,$reqtime, $t0->[0]));


Apache::LogFormat::Compiler allows to add custom format string

  my $log_handler = Apache::LogFormat::Compiler->new(
      char_handlers => +{
          'z' => sub {
              my ($env,$req) = @_;
              return $env->{HTTP_X_FORWARDED_FOR};
      block_handlers => +{
          'Z' => sub {
              my ($block,$env,$req) = @_;
              # block eq 'HTTP_X_FORWARDED_FOR|REMOTE_ADDR'
              my ($main, $alt) = split('\|', $args);
              return exists $env->{$main} ? $env->{$main} : $env->{$alt};

Any single letter can be used other than Apache::LogFormat::Compiler used. Your sub is called with two or three arguments the content inside the {} from the format (block_handlers only), PSGI environment ($env), and ArrayRef of the response. It should return the string to be logged


Masahiro Nagano <>




Copyright (C) Masahiro Nagano

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

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