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Log::Report::Extract::Template - collect translatable strings from template files


   is a Log::Report::Extract


 # First use of this module: extract msgids from various kinds
 # of text-files, usually web templates.
 # See script "xgettext-perl" for standard wrapper script

 my $extr = Log::Report::Extract::Template->new
   ( lexicon => '/usr/share/locale'
   , domain  => 'my-web-site'
   , pattern => 'TT2-loc'
 $extr->process('website/page.html');  # many times

 # Second use: connect to Template::Toolkit
 # See DETAILS chapter below

 [% loc("Greetings {name},", name => %]
 [% | loc(name => %]Greetings {name}[% END %]
 [% 'Greetings {name}' | loc(name => %]


This module helps maintaining the POT files which list translatable strings from template files (or other flat text files) by updating the list of message-ids which are kept in them.

After initiation, the process() method needs to be called for each file in the domain and the existing PO files will get updated accordingly.

If no translations exist yet, one $textdomain.po file will be created as point to start. Copy that file into $textdomain/$lang.po

Extends "DESCRIPTION" in Log::Report::Extract.


Extends "METHODS" in Log::Report::Extract.


Extends "Constructors" in Log::Report::Extract.

 -Option --Defined in          --Default
  charset  Log::Report::Extract  'utf-8'
  domain                         <required>
  lexicon  Log::Report::Extract  <required>
  pattern                        <undef>
charset => STRING
domain => DOMAIN

There is no syntax for specifying domains in templates (yet), so you must be explicit about the collection we are making now.

lexicon => DIRECTORY

See the DETAILS section below for a detailed explenation.


Extends "Accessors" in Log::Report::Extract.

$obj->addPot($domain, $pot, %options)

Inherited, see "Accessors" in Log::Report::Extract


Inherited, see "Accessors" in Log::Report::Extract


Inherited, see "Accessors" in Log::Report::Extract


Inherited, see "Accessors" in Log::Report::Extract


Inherited, see "Accessors" in Log::Report::Extract


Extends "Processors" in Log::Report::Extract.


Inherited, see "Processors" in Log::Report::Extract

$obj->process($filename, %options)

Update the domains mentioned in the $filename. All textdomains defined in the file will get updated automatically, but not written before all files where processed.

 -Option --Default
  charset  'utf-8'
  pattern  <from new(pattern)>
charset => STRING

The character encoding used in this template file.


Read the DETAILS section about this.

$obj->showStats( [$domains] )

Inherited, see "Processors" in Log::Report::Extract

$obj->store( $domain, $filename, $linenr, $context, $msg, [$msg_plural] )

Inherited, see "Processors" in Log::Report::Extract

$obj->write( [$domain] )

Inherited, see "Processors" in Log::Report::Extract


Scan Patterns

Various template systems use different conventions for denoting strings to be translated.

Predefined for Template-Toolkit

There is not a single convention for translations in Template-Toolkit (see Template), so you need to specify which version TT you use and which function name you want to use. In extreme cases, you may even build separate translation tables by simply providing using functions.

For instance

   pattern => 'TT2-loc'

will scan for

  [% loc("msgid", key => value, ...) %]
  [% loc('msgid', key => value, ...) %]
  [% loc("msgid|plural", count, key => value, ...) %]
       title = loc('something')
  [% | loc(n => name) %]hi {n}[% END %]
  [% 'hi {n}' | loc(n => name) %]

For TT1, the brackets can either be '[%...%]' or '%%...%%'. The function name is treated case-sensitive. Some people prefer 'l()' or 'L()'.

The code needed

  # during initiation of the webserver, once in your script (before fork)
  my $lexicons   = 'some-directory-for-translation-tables';
  my $translator = Log::Report::Translator::POT->new(lexicons => $lexicons);
  my $domain     = textdomain $textdomain;
  $domain->configure(translator => $translator);

  # your standard template driver
  sub handler {
     my $vars      = { ...all kinds of values... };
     $vars->{loc}  = \&translate;           # <--- this is extra

     my $output    = '';
     my $templater = Template->new(...);
     $templater->process($template_fn, $vars, \$output);
     print $output;

  # anywhere in the same file
  sub translate {
    my $textdomain = ...;   # your choice when running xgettext-perl
    my $lang       = ...;   # how do you figure that out?
    my $msg = Log::Report::Message->fromTemplateToolkit($textdomain, @_);

To generate the pod tables, run in the shell something like

  xgettext-perl -p $lexicons --template TT2-loc \
      --domain $textdomain  $templates_dir

If you want to implement your own extractor --to avoid xgettext-perl-- you need to run something like this:

  my $extr = Log::Report::Extract::Template->new
    ( lexicon => $output
    , charset => 'utf-8'
    , domain  => $domain
    , pattern => 'TT2-loc'
  $extr->process($_) for @filenames;

Use in combination with contexts

This example extends the previous with using context sensitive translations, as implemented by Log::Report::Translator::Context.

Let's say that the translation of some of the sentences on the website depend on the gender of the addressed person. An example of the use in a TT2 template:

  [% loc("{name<gender} forgot his key", name => %]

The extraction script xgettext-perl will expand this into two records in the PO file, respectively with msgctxt attribute 'gender=male' and 'gender=female'.

When your PO-files are not generated by 'xgettext-perl', you do not need a separate domain configuration file:

    ( context_rules => +{gender => ['male','female']}
    , translator    => $translator

When your PO-files are generated by 'xgettext-perl', you need to share the context-rules between that msgid extractor and your runtime code. That same file needs to be passed with the 'domain' parameter to the script.

  # add context_rules either explicit or via 'config' filename
    ( config     => 'my/own/$domain.conf'
    , translator => $translator

Now, when you generate the pages, you need to set-up the right context. In this case, we set-up the gender of the person who gets addressed. (The name 'gender' is good for examples, but quite non-descriptive. Maybe 'user_gender' is more maintainable)

  $domain->setContext( +{gender => 'male'} );  # or ('gender=male')
  $domain->setContext( "gender=male" );        # same


This module is part of Log-Report-Lexicon distribution version 1.11, built on March 22, 2018. Website:


Copyrights 2007-2018 by [Mark Overmeer <>]. For other contributors see ChangeLog.

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