mod_perl2 User's Guide
By Stas Bekman, Jim Brandt
By Stas Bekman, Eric Cholet
On CPAN you will be able to find a number of Perl modules created to run under mod_perl. We will give a presentation of them here and ways to get at these modules.
Apache/Perl modules are somewhat different from the many others found on CPAN (http://www.cpan.org/). Most Perl modules are "building blocks"; developers use them to build applications or even more building blocks. It just so happens that Apache/Perl modules are encapsulated inside a namespace and .pm file. However, this does not make them all building blocks, many are just like Apache modules written in C: you install them, edit the server configuration files and you're done.
Before you start a new module, consider this: Apache/Perl modules are
useless outside of mod_perl and Apache. Do your best to design such
Apache::* module will make good use of the building
blocks found on CPAN, putting together new building blocks where
appropriate and simply glue them together with the Apache API, keeping
Apache::* modules very small.
These modules will also serve as good examples, showing you where
modules can step in during a stage of a request with
callbacks. You'll also see how and when to use the Apache API
Like other CPAN modules, the Apache/Perl modules are listed on the
Perl module list, under the World Wide Web category:
. Browse down the page to find the
Apache:: modules, organized by
their role in the request cycle.
Modules listed with the APML as is contact are part of the mod_perl distribution package. Other modules can be found on CPAN in the http://www.cpan.org/modules/by-module/Apache/ directory. If they have not made it to CPAN yet, they might be found in the mod_perl contrib directory at http://perl.apache.org/dist/contrib/. Otherwise, feel free to ask the contact author or the list how you can go about getting your hands on a copy. The modules listed with MPB as the author were present in the Writing Apache Modules with Perl and C book by Lincoln Stein and Doug MacEachern. If you can't find these modules on CPAN, look for them at http://modperl.com:9000/book/source/.
Apache and Perl are world-wide collaborative efforts; naturally, the Apache/Perl integration project is the same. You've started on the right foot simply by reading this document, thanks! Please make sure you've read the main Perl module list at http://www.cpan.org/modules/00modlist.long.html, all that is said there is relevant here!
If you wish to share your module(s) in the Perl way, by putting them on CPAN, send a request to firstname.lastname@example.org to get set up with a PAUSE user id and directory. See http://www.cpan.org/modules/04pause.html for more details.
HINT: For a nice set of template files try this:
% h2xs -AX -n Apache::YourPackageName
Like for normal Perl modules on CPAN, the
conventionally used for mod_perl modules needs to keep a certain
organization. This is why you should choose a multi-level name for
your module, categorizing it into a namespace that you feel fits your
module. There should be a very good reason for a module to not have a
nested name (ie. living directly under
Apache::), that should only
be the case for the core API modules and older modules which may keep
Here are some examples of namespaces that you may want to use:
Apache::App Applications: any module serving content with a point-and-click interface * Apache::Auth Modules related to general user authentication/authorization Apache::Authen Modules solely related to authentication Apache::Authz Solely related to authorization Apache::Access Only access control Apache::Config Configuration-related things Apache::Devel Development-related modules (debug/devel help) Apache::Filter Filtering modules ::Output Output filters (1.0 style Filter/OutputChain or 2.0 style) ::Input Input filters Apache::Framework Modules providing application frameworks (templating and/or publication frameworks) * Apache::Log Logging modules Apache::Method Method handlers (PATCH/PUT and the like) Apache::MIME MIME-type modules Apache::Monitor Monitoring modules Apache::Persistent Modules providing for persistency in connections Apache::Proxy Proxies Apache::RPC RPC/SOAP modules Apache::Trans URI Translation handlers Apache::Util General-utility modules, usually not handlers but providing an API to use in your code
*: If you are writing a small application or templating module,
contained in one module, you can use these namespaces. However, if you
are planning a substantial framework with many inter-related modules,
you should probably go with a top-level namespace outside of
For an illustration of how this would look for the older modules, you can look at this example categorization.
Note: Of course none of these categories are cast in stone: you
should feel free to choose the module name that suits your module best
instead of trying to follow these general indications. If in doubt,
just ask around at the mod_perl list; you are sure to get some
assistance in naming your module! Furthermore, you should look at the
way it's done on CPAN, and apply it under the
The following modules have already been ported to mod_perl 2.0 and are available from CPAN. If you know of other modules that have been ported but not listed here, please contact the modperl list, so we can update this information:
Module Name Required Dist Package -------------------------------------------------------- Apache::ASP Apache-ASP-2.55 Apache::DBILogin Apache-DBILogin-2.03 Apache::AuthCookie Apache-AuthCookie-3.05 Apache::AuthExpire Apache-AuthExpire-0.38 Apache::AuthNetLDAP Apache-AuthNetLDAP-0.25 Apache::AuthPerLDAP Apache-AuthPerLDAP-2.01 Apache::AuthenNTLM Apache-AuthenNTLM-2.04 Apache::AuthenPasswd Apache-AuthenPasswd-0.12 Apache::AuthenSmb Apache-AuthenSmb-0.70 Apache::AuthenURL Apache-AuthenURL-2.02 Apache::AuthzNetLDAP Apache-AuthzNetLDAP-0.07 Apache::AuthzPasswd Apache-AuthzPasswd-0.11 Apache::Clean Apache-Clean-2.00_4 Apache::DB Apache-DB-0.10 Apache::DProf Apache-DB-0.10 Apache::GeoIP Apache-GeoIP-1.215 Apache::PAR Apache-PAR-0.30 Apache::Peek Apache-Peek-1.03 Apache::Scoreboard Apache-Scoreboard-2.01 Apache::SessionManager Apache-SessionManager 1.00 Apache::SmallProf Apache-DB-0.10 Apache::Syntax::Highlight::Perl Apache-Syntax-Highlight-Perl-1.00 Apache::VMonitor Apache-VMonitor-2.0 CGI CGI.pm-3.10 CGI::Cookie CGI.pm-3.10 (comes in the CGI dist) Apache::Request Apache2-Request (comes in libapreq2 dist)
The following modules are in the process of being ported to mod_perl 2.0. Please contact the porter if you wish to help the porting.
If you have started the porting, in order to avoid duplicated efforts please contact the modperl list, and let us know what module you are porting. This information should also help others to help you to do the porting and testing.
Module Porters ---------------------------------- Apache::Language Philippe M. Chiasson <gozer AT cpan.org> Apache::AutoIndex Philippe M. Chiasson <gozer AT cpan.org> Apache::Icon Philippe M. Chiasson <gozer AT cpan.org> Apache::Template Geoffrey Young <geoff AT modperlcookbook.org> Apache::AuthzNIS
The following modules have gone beyond the porting stage and are specifically designed for mod_perl 2.0 and the new features and functionality it brings. Each is available from CPAN. If you know of other modules that have been written for the 2.0 API but not listed here, please contact the modperl list, so we can update this information:
Module Maintainers ------------------------------------------------ Apache::AuthenHook Geoffrey Young <geoff AT modperlcookbook.org> Apache::IncludeHook Geoffrey Young <geoff AT modperlcookbook.org> Apache2::DebugFilter Philip M. Gollucci <pgollucci AT p6m7g8.com> Apache2::Filter::HTTPHeadersFixup Philip M. Gollucci <pgollucci AT p6m7g8.com>
The maintainer is the person you should contact with updates, corrections and patches.
Per Einar Ellefsen <pereinar (at) oslo.online.no>
Per Einar Ellefsen <pereinar (at) oslo.online.no>