Project Ragnaroek - The Road towards Midgard 2
Note: this document is still in proposal stage. Definite decisions on the roadmap towards Midgard 2 have not yet been made.
- 2003-03-29: Added Martin's notes to Application server evaluation
- 2003-03-28: Added Alexander's notes to Application server evaluation
There have been several attempts at rewriting Midgard in the past, most notably the separate Midgard 2 development projects lead by Jukka Zitting (2000) and Ami Ganguli (2001). However, these attempts have not been able to produce results.
Important point here is that rewrites are very difficult for Open Source projects. Volunteer contributions usually rely on the fact that contributors can receive something immediately usable from their efforts. Because of this it is important to implement Project Ragnarok on existing infrastructure, minimizing effort needed for producing results.
What is Ragnaroek?
Ragnaroek (Ragnarøk) is the final battle between gods and giants in Nordic mythology. After the final battle a new world will be built on the ruins.
What is Midgard?
The first part in planning a rewrite of Midgard's architecture is to understand what Midgard actually is. In the discussions so far the following has appeared:
- Midgard is a Web Content Management Framework for medium-sized websites
- Midgard is simple and quick to implement
- Midgard is international, enabling creation of global websites
There are several important goals for the Midgard rewrite:
- Cleaner, more maintainable codebase (possibly using a scripting language)
- Enabling creation of new Midgard object types
- Fewer API dependencies
- Persistent application server
- Building on existing software
- Multiplatform, easier installation
- Moving MidCOM to Midgard core
- Aligning Midgard more closely with the PHP community
Midgard has several important aspects that should be retained in the rewrite:
- International support: UTF-8, Multilang
- Keeping PHP as the "site development language"
- GNU licensing
- Backwards compatibility (target: 90%)
Idea discussed by Henri Bergius, Torben Nehmer and David Schmitter in OSCOM Sprint Zurich was to base the new Midgard 2 on top of an existing application server. Ideas presented included Zope and JBOSS.
In this case the application server would provide data management services. Midgard API would be provided by a PHP-level library, preferably available from PEAR. The library would communicate with the application server using a RPC protocol like SOAP or XML-RPC. HTTP query handling would be managed by a lightweight Apache 2 module.
Using an existing application server would simplify development, as it would be only required to write the needed Midgard object classes for that application server. Also, since all data would be managed by the application server the PHP library could be relatively lightweight. Using an Apache module instead of mod_rewrite like Midgard Lite does would allow greater flexibility and keep the Midgard name in Apache response headers. Preferably Midgard 2 would be also runnable without the Apache module.