XForms Everywhere

Most of the time, we use the address bar in Firefox to type the address of a web site. But we can also use it to configure Firefox or get detailed information about plugins, the cache, and other things by typing a URI that starts with “about:”.

When you create a bookmark in Firefox, you can also assign a keyword to that bookmark. Typing the keyword in the address bar will take you to the corresponding bookmark location. The interesting thing is that Firefox will replace the string %s in the URL by any text that you have typed after the keyword in the address bar. Let’s use this to quick searched in the PresentationServer user guide from the Firefox address bar:

1. Right click on OPS keyword, choose Bookmark This Link, and click OK.
2. Open the bookmarks (ctrl-b), right click the bookmark you just added, and type “ops” in the Keyword field.

That’s it. Now you’re looking for the documentation about the PresentationServer file serializer? Easy: just type ops file serializer in the address bar. The first link in the Google result it the one you are looking for.

The weekend is a time for leisure and recreation. So I’ll take the opportunity and talk about something different, something non-technical.

Malcolm Gladwell is the author of the bestsellers The Tipping Point: How Little Things Can Make a Big Difference (2002), which I can highly recommend, and Blink: The Power of Thinking Without Thinking (2005). He writes in an engaging way about sociology, psychology, and human communication. The implications of his ideas are inspiring for people interested in consumer behavior and business in general. When Malcolm speaks, people listen, so we can be sure that the blog he has just started will be very popular. The few entries he wrote so far focus on “setting the record straight” relative to other articles he published in the past, but something tells me that Malcolm will find more interesting ways to use his blog, as he becomes more familiar with the medium.

Michael Kay (XML guru, editor the XSLT 2.0 specification, and author of Saxon an excellent XSLT and XQuery processor), published an article on using XML technologies to build workflow applications. He describes workflow applications as “applications that one can think of in terms of documents moving around a community of people who each perform particular tasks”. He explains why XML and standard XML technologies like XSLT, XQuery, XML Schema, or XForms, are a very good fit to implement workflow applications. He also has some nice words for our product, PresentationServer:

[…] There are various tools you could use in this role, but most of them are completely general-purpose. I would recommend instead that you consider an approach that specialized for handling XML. An example that I have used very successfully is the Orbeon PresentationServer (www.orbeon.com).

In 2003, we published an article where we were making a very similar point: while most people still design applications around data models and operations, your architecture becomes simpler when you think in terms of documents and processes. Documents are in XML, and XML standards provide all the tools to process those documents, for instance: XForms to capture data with forms, XML databases to store it, XQuery to extract information, XSLT to transform XML into HTML.

One the big difference between open source and closed source projects is that open source projects have a natural tendency to create a community around the project. In the world of closed source software, people have well defined roles, like user, QA, developer, project manager, or program manager. In the open source community the difference between roles becomes less relevant: the same person can one day be a user of the product, the next day find a bug, and a day after that fix the bug and submit a patch to the community.

Because roles are relatively unimportant, everyone can talk to everyone. This shortens the distance between people, in particular between those who are using the product, and know very well about the features they need, and those who spend most of their time implementing new features in the product.

Benefits go both ways: if you have a feature to suggest, you know your voice will be heard, that your request be discussed, and is likely to be taken into account. If you are working on the product, you can get ideas about new features from the community and discuss those ideas with the community.

To a great extent, in an open source project, the community is in fact your project manager.

I will be in Cannes-Mandelieu (south of France) next week for face to face meetings involving the W3C working groups of which we are members, namely the XForms working group and the XML Processing working group.

The XForms working group has been active for quite a long time, as it has already produced the XForms 1.0 recommendation back in 2003, and is on the verge of publishing the second edition of XForms 1.0 as an official W3C recommendation. On the other hand, the XML Processing working group has just started. For this reason, the two groups have a very different dynamic which will be very interesting to observe and interact with.

We are very happy to help making these two technologies progress, as we think they are absolutely crucial for the web.

Mark Birbeck has recently published a good tutorial showing how you can use XForms to query Flickr for images matching one or more tags, and then display the resulting images while controlling their size with a slider. We have now included a variation on this example in OPS. Check it out live here!

You can browse and download the source code right here.

Relax, sit back, and enjoy in just under 10 minutes a guided tour of the most interesting OPS XForms examples including XForms Controls, To-Do List, Instant Translation, and the DMV Forms sample application. The screencast is available in small format for full-size format.

Orbeon PresentationServer (OPS) 3.0 is finally out, and we are quite happy about that! But it took us a while to get there. For most of OPS’s history (and before that OXF’s), we have tried and often managed to stick to a “release early, release often” strategy, by aiming at releasing something stable every 4 to 8 weeks. We sometimes succeeded, sometimes not. However, between the last two stable versions of OPS (2.8 and 3.0), the gap was much bigger than usual: a little bit over 30 weeks.

There is of course an explanation for this fact: the task of rewriting the XForms engine almost entirely was daunting, more so than we expected. We not only had to design the client-server architecture (which we presented in its broad lines at XTech in May 2005 already, with working examples), but to implement it, write the server-side XForms engine, write the client-side functionality (with all the JavaScript fun), integrate it nicely with the rest of OPS, provide examples and documentation, etc.

During all that time, the code was never in a drastically unstable state. In particular, we managed to keep backward compatibility with our XForms Classic engine; we managed to fit the new XForms architecture very nicely into the Page Flow Controller (PFC), in fact simplifying existing concepts in the process; we also initially based the new XForms NG engine on a refactoring of our existing XForms Classic code, and now things work the other way around, with the XForms Classic engine leveraging what it can of the XForms NG engine.

We could of course have released some intermediate stable releases with updates to OPS 2.8 features, but those would have disrupted the development of OPS 3.0. Instead, we released betas: in mid-July, early September, and early December 2005, with time between releases of 18 weeks, 6 weeks, 12 weeks, and 6 weeks respectively. What is the difference between beta releases and a “final” release? Obviously, it makes a difference in user perception to call something “final” as opposed to calling it “beta”. But we also had some objective measures, including a minimal set of features and bug-fixes we deemed absolutely necessary, as well as polishing of the examples and documentation.

With hindsight, it still looks like there was no easy way around the longer development cycle for OPS 3.0. But we can now aim at releasing stable versions more often again, because the bulk of the new XForms engine is in place and incremental updates are more reasonable to contemplate.

Intalio and Orbeon announced today that Intalio has selected PresentationServer as their front-end to Intalio|BPMS 4.0. Intalio|BPMS is a Business Process Management System (BPMS). It includes a BPEL engine, an Eclipse-based graphical process designer, and a workflow component that lets people interact with business processes. Interactions are done through forms, forms are designed in XForms, and the Intalio workflow component now includes PresentationServer, which is used for XForms rendering and processing. Check out the announcement as well as Intalio’s web site.

Orbeon PresentationServer now features an improved source code viewer.

The viewer uses XForms to display the list of files with the Repeat module. It also uses an XForms submission to call a server-side formatting service which returns the content of the file marked up with HTML, either as a simple text version which preserves all the details of the original source file, or as an optional syntax-highlighted version for XML files.

Thanks to the Ajax-based XForms engine, the viewer allows you to navigate between files or change the viewing mode without the page ever reloading. It also has a “download” function which allows you to directly downlad a source file.

You can access the viewer by selecting the “View Source” tab of each example. It is also possible to link directly to a particular source file.