Jeni's Musings

For the last several months, I’ve been working on a project at TSO for publishing UK legislation using a native XML database (eg eXist or MarkLogic Server) with some middleware (eg Orbeon or Cocoon). It’s a powerful and flexible approach that’s built on declarative languages like XQuery, XSLT, and XML pipelines; you can see it in action with the Command and House Papers demo.

But the killer platform isn’t quite here yet, partly because the specs aren’t quite done. Both Orbeon and Cocoon use XML pipelines, but they use different languages to define them; XProc is just around the corner. XML databases are all over the place in their conformance to XQuery, its optional features and the not-quite-finalised specs for free-text searching and updating.

People talk about how productive you can be using Ruby on Rails or Django, and they work great for publishing data you can store in a relational database. What we need is a similarly easy-to-use platform for document-oriented, XML-based content. This is my wish-list.

A lot of people run into problems with namespaces, and most of those arise from using default namespaces (ie not giving namespaces prefixes). The transformation technology you use can have a big effect on how confusing and irritating it gets.

Default namespaces make XML documents easier to read because they allow you to just give the local name of an element rather than using prefixes all over the place. For example, using:

<house status="For Sale" xmlns="http://www.example.com/ns/house">
  <askingPrice>...</askingPrice>
  <address>...</address>
  <layout>...</layout>
</house>