Handel::Manual::About - A few words about the Handel Framework.


Handel is a cart/order/checkout framework with AxKit taglib support , TT2 (Template Toolkit) support and Catalyst::Helper support. It was created for the conversion of an IIS/ASP based commerce site to Apache/ModPerl, but I decided that it might be useful to others so here it is.

For the curious, Handel is German for commerce.


You can get the latest news, source, documentation and wiki help at


You can browse the latest source code at, or get the latest version of the source code from the Handel subversion repository at


Join the mailing list at Big thanks to gabb@#catalyst for the list space.


I can be found most nights on IRC in the following channels: 


The Handel philosophy is to provide a framework of reusable parts and not an entire solution. No two shopping carts or checkout processes are alike so it's impossible to create The One Great Solution.

Handel is built in layers, each of which should and can be reusable on their own. The storage layer deals with mapping generic actions like adding items, creating carts, etc to specific storage mechanisms like DBIC, DBI, XML, etc. The interface classes, like Handel::Cart, take care of providing one possible public API for consuming the storage layer classes.


Database Agnostic

Thanks to DBIx::Class and a general avoidance of auto incrementing ids, Handel should run in any database that DBIx::Class supports.

Schema Agnostic

The default schema isn't enough for everyone. Some have existing schemas in place, and some just need to add a field or two. Handel aims to have the ability to use as many disparate schema configurations as possible through a storage layer to abstract schema access without hardcoding specifics in the top level Cart/Order/Item classes.

Implementation Agnostic

Handel should be able to be used from the command line, from a web page, from a SOAP service, or from a GUI application. It's simply a data access mechanism. Any interaction with forms, web pages, browsers, cookies, etc is the responsibility of the consumer/programmer.

Checkout Agnostic

A checkout process means different things to different people in different situations. The Handel checkout pipeline by itself does absolutely nothing with an order. Instead, it's a plugin manager that allows you to specify and build plugins to do various actions (payment authorization, address validation, fax delivery, etc). Each site, server, page, even process() call can have its own unique order processing pipeline.

Easy Integration

Handel aims to provide as much glue as possible for existing application and page templating systems.


Basic Add/Edit/Delete/Save/Restore Cart Operations

What cart would be complete without the usual operations: add, update, delete, save, and restore.

Plugin Based Order Processing Pipeline

With just a few lines of code, you can utilize the power of CPAN to add address validation, credit card authorization, or even email confirmations to your checkout process. With a building block style order processing pipeline, your checkout process can be as easy or as complex as you need it to be.

Runs On Any Database

Handel runs on any database that DBIx::Class supports. That list includes, but is not limited to SQLite, MySQL, Postgres, DB2, MSSQL, and Oracle. In theory, it should also work and any generic DBI driver that can handle table relations and join statements.

Currency Conversion and Formatting

Handel includes support for currency conversion and formatting on all currency related fields.

Highly Customizable

Choose your level of dragons. You can use the default schema, adding column or two, or go full tilt and use a completely different schema.

Easy Integration with Catalyst

Handel includes Catalyst::Helper modules to make adding Handel functionality into a Catalyst website as easy as possible.

Easy Integration with AxKit

Handel includes basic Cart/Order/Checkout taglibs for use inside of AxKit XSP pages.

Easy Integration with Template Toolkit

Handel includes Cart/Order/Checkout plugins for those who use Template Toolkit as their page language of choice.


Handel is a framework to enable simple cart and order record maintenance with a plugin based checkout process.


Handel is not Intershop, Cart32, WebGUI, a CMS or a complete web commerce package(1).

(1) While it is not a complete web based commerce system, I do plan on having feature complete working demos sites so people can still quick-start their own projects. There is also a Catalyst/Handel commerce project in the works called Mango.


I big shout at to the DBix::Class folk for all the support. Without the flexibility that DBIx::Class provides, Handel would be a much less flexible.


    Christopher H. Laco