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Apache::PageKit Frequently Asked Questions $Id: FAQ.pod,v 1.7 2004/01/06 16:31:47 borisz Exp $
Last updated: Sep 26th, 2003

NAME

Apache::PageKit::FAQ -- The Frequently Asked Questions for Apache::PageKit

SYNOPSIS

    perldoc Apache::PageKit::FAQ

DESCRIPTION

This document serves to answer the most frequently asked questions for Apache::PageKit.

Basic Information & Information Sources

1.1 What is Apache::PageKit?

PageKit is an mod_perl based application framework that uses HTML::Template and XML to separate code, design, and content. Includes session management, authentication, form validation, co-branding, and a content management system.

Its goal is to solve all the common problems of web programming, and to make the creation and maintenance of dynamic web sites fast, easy and enjoyable.

1.2 Where can I get it from?

The Comprehensive Perl Archive Network.

Apache::PageKit may be downloaded from CPAN via:

    http://www.perl.com/cgi-bin/cpan_mod?module=Apache-PageKit

    http://search.cpan.org/search?dist=Apache-PageKit

1.3 Apache::PageKit uses XML, what is it?

XML (eXtensible Markup Language) is a way to store data and meta-data. The meta-data gives applications the ability to 'understand' the data and work with it in an intelligent fashion. For more information check the sites below:

  http://www.w3.org/TR/1998/REC-xml-19980210
  http://www.xml.com/

1.4 Apache::PageKit uses XSLT, what is it?

XSLT (eXtensible Stylesheet Language: Transformations)

  http://www.w3.org/TR/xslt
  http://www.w3.org/Style/XSL/
  http://www.xslinfo.com/
  http://www.oasis-open.org/cover/xsl.html
  http://www.xml.com/

XSLT is a language used to apply transformations to XML. This powerful tool helps seperate Content from the Presentation by changing the way the XML is presented to the end user. It can be used to reformat the XML into HTML, WML, XML, PDF, POD or any other template you come up with.

1.5 Is there a webpage with more information about Apache::PageKit?

Yes, http://www.pagekit.org and http://sourceforge.net/projects/pagekit/

1.6 Is there a mailing list?

Yes, one for users and one for developers.

To subscribe look here:

    http://lists.sourceforge.net/mailman/listinfo/pagekit-users
    http://lists.sourceforge.net/mailman/listinfo/pagekit-devel

1.7 Is there a mailling list archive?

Yes,

  http://www.geocrawler.com/redir-sf.php3?list=pagekit-users
  http://www.geocrawler.com/redir-sf.php3?list=pagekit-devel

Installation

2.1 Apache segfaults on start, but only with Apache::PageKit. What is wrong?

Apache is often compiled with the expat-lite library which is incompatible with the XML::Parser module. PageKit prior to 1.08 requires XML::Parser. You'll have to compile Apache with --disable-rule=expat for these early versions of PageKit.

It is recommended that you upgrade to PageKit 1.08 or higher, which doesn't require XML::Parser or expat. However, if your code uses XML::Parser Apache will still segfault. In this case you must recompile Apache with --disable-rule=expat or remove dependencies on XML::Parser in your code.

The mod_perl guide has an excellect section on compiling mod_perl and Apache from source. http://perl.apache.org/guide/

2.2 Do I really need to recompile Apache? It works without Apache::PageKit.

No, if you use Apache::PageKit >= 1.08 and promise to never use XML::Parser. Else yes, you must recompile Apache.

2.3 perl Makefile.PL result in Can't locate Apache/test.pm in @INC ...

You use mod_perl-1.28 or higher. Apache::test is obsolete and renamed to Apache::testold. The future is Apache::Test. To get around the error type

  perl -i -pe 's/Apache::test\b/Apache::testold/g' Makefile.PL

Or even better upgrade Apache::Pagekit to a version > 1.11. There we use Apache::Test.

2.4 I can not build libapreq or it stops working after a reboot.

You use perl >= 5.8.1 which includes a new version of ExtUtils::MakeMaker. Read more here: http://marc.theaimsgroup.com/?l=perl5-porters&m=105981649201380&w=2 http://marc.theaimsgroup.com/?l=apreq-dev&m=106146287323705&w=2

To fix the problem apply this patch from Steve Hay or use libapreq-1.3

  --- c/Makefile.PL.orig    2001-04-03 20:24:12.000000000 +0100
  +++ c/Makefile.PL 2004-08-21 11:31:42.000000000 +0100
  @@ -34,7 +34,8 @@
   sub MY::dynamic {
       my $self = shift;
       my $string = $self->MM::dynamic;
  -    $string =~ s/(Makefile\s+).*/$1/g;
  +    $string =~ s{ \$\(INST_DYNAMIC\)}{}g;
  +    $string =~ s{ \$\(INST_BOOT\)}{}g;
       $string;
   }

Migrating to Apache::PageKit from...

3.1 I already have a website and I want to extend it with Apache::PageKit. Where can I put my data?

You have several options, some follows.

  • Copy your whole site into the directory View/Default/. Of the edited eg site of Apache::PageKit.

  • Copy the eg site of Apache::PageKit to a directory in the rootdir of your site ie:

      cp -R .../Apache-PageKit-x.yz/eg .../htdocs/.../pagekit

    edit MyModel/Model.pm, MyModel/Common.pm and Config/Config.xml and add Apache::PageKit as the handler for this dir in yout httpd.conf.

Apache::PageKit beginner's FAQ's

4.1 Can I run more as one site with one Apache Server?

Sure, as long as the Perl Classes don't conflict. (You can't run both production and development PageKits on the same server, unless you make sure that the Classes have different names.) You will also have to make sure that the PKIT_ROOT and cache_dir configuration option are distinct for each server. If cache_dir is not set for either of them, that should be fine, since it defaults to PKIT_ROOT/View/pkit_cache.

To set up, use the Apache <Location> or <Files> configuration directives.

4.2 Can I use Apache::PageKit inside Apache <VirtualHost> configuration directives?

Sure, you have to provide uniq sets of PageKit-modules and a uniq pkit_cache dir thats all.

xxxx

5.1 Is it possible to use expressions in <(MODEL|CONTENT)_(IF|UNLESS|VAR)> tags?

Yes, you have to use Apache::PageKit 1.08 or higher. In your Config/Config.xml change or add this line in the global section:

  template_class = "HTML::Template::Expr"

For more information type perldoc HTML::Template::Expr.

5.2 I'm using loop_context_vars as descriped in the HTML::Template manual within my <CONTENT_(IF|UNLESS)> tags, but it did not work.

As an undocumented feature of HTML::Template, loop_context_vars must be written in lowercase if your template is case_sensitive. <CONTENT_...> is case sensitive. So change __FIRST__, __LAST__, __INNER__, __ODD__ to __first__, __last__, __inner__, __odd__.

5.3 How do I deal with uploads?

If you call $model->apr->upload; Then this will return a single Apache::Upload object in a scalar context or all Apache::Upload objects in an array context. This is because $model->apr returns a Apache::Request object.

5.4 My Database busted after some time - What is wrong?

You did not use Apache::DBI. Load (use) Apache::DBI in your startup.pl file. If for some reason the use of Apache::DBI is not possible, close the connection in the pkit_cleanup methode.

something like this will do:

  sub pkit_cleanup {
    my $dbh = shift->dbh;
    $dbh && $dbh->disconnect;
  }

PageKit on Operatingsystem X

6.1 Did PageKit run on my systems?

Pagekit is known to run at least on the following systems:

  Darwin 6.4 powerpc
  FreeBSD 4.3
  FreeBSD 4.4
  FreeBSD 4.5
  FreeBSD 4.6
  HP UX 10
  HP UX 11
  Linux 2.2
  Linux 2.4
  Solaris 7 x86
  Solaris 8 sparc
  Solaris 8 x86
  Solaris 9 sparc
  Win 2000
  Win ME
  Win NT

6.3 My OS did not support flock, what can i do?

Add *CORE::GLOBAL::flock = sub {1};

to your startup.pl or in your httpd.conf file inside a <Perl> block:

  <Perl>
    *CORE::GLOBAL::flock = sub {1};
  </Perl>

Troubleshooting

I'm using MySQL Apache::Session store class and I'm getting DBD::mysql::st execute failed: Duplicate entry errors

This appears to be a DBD::mysql issue - see http://rt.cpan.org/NoAuth/Bug.html?id=1717 A workaround is to stringify the session_id if it is a number.

My sessions do not work. I'm using perl 5.8 and Apache::SessionX 2.00b3.

Install MD5. It is not part of perl core anymore. Or install this patch:

  --- SessionX/Generate/MD5.pm.orig     2002-11-11 08:35:54.000000000 +0100
  +++ SessionX/Generate/MD5.pm  2002-11-11 08:37:44.000000000 +0100
  @@ -12,12 +12,12 @@

   use strict;
   use vars qw($VERSION);
  -use MD5;
  +use Digest::MD5;

   $VERSION = '2.1';

   sub generate {
  -    my $session = shift;
  +    my $session = shift;
       my $arg = shift;
       my $length = 32;

  @@ -26,7 +26,7 @@
       }

       $session->{data}->{_session_id} =
  -        substr(MD5->hexhash(MD5->hexhash($arg || (time(). {}. rand(). $$))), 0, $length);
  +        substr(Digest::MD5::md5_hex(Digest::MD5::md5_hex($arg || (time(). {}. rand(). $$))), 0, $length);


   }

VERSION

This document is currently at version 0.03, as of Feb 10th, 2003.

AUTHORS

Boris Zentner (bzm@2bz.de)

TJ Mather (tjmather@tjmater.com)

CREDITS

Fixes, Bug Reports, Docs have been generously provided by:

  Tomasz Konefal
  Anton Permyakov
  Vladimir Bogdanov
  Rob Starkey
  Eugene Rachinsky

Parts of this FAQ are taken from the Apache::PageKit distribution and the website at http://www.pagekit.org/.

COPYRIGHT

Copyright (c) 2001 TJ Mather Copyright (c) 2002, 2003, 2004 Boris Zentner

LICENSE

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