Monday, July 13, 2009

Standalone DocBook editor is ready!

Finally finished the DTD for all the tags :) *phew*

Also added a document tree which helps easy navigation, addition and deletion of elements etc. Please check this feature out here. It is really cool.

Checklist: Deliverable 1 done.

For the other two deliverables,test results and documentation, I have an idea. I will write the documentation in DocBook format using Beacon itself.

Note: Since the demo is still in testing do not trust your documents with it yet. We'll make it stable soon. Better yet, it would be great if community could report bugs/suggestions. :)

Saturday, July 11, 2009

XSLs done!

Finally sent my XSLs to Nandeep for review yesterday. He must have committed it by now.
Also found a DocBook CSS which publican uses and replaced the existing one. Using the same CSS might help in integrating later on.

Will finish the DTD today.

Now off to fill the mid term evaluation form...

Tuesday, July 7, 2009

What's Next

Mid-terms evaluations are knocking on door and its been quite a wild ride coding. Web development is a different ball game altogether and I am beginning to understand why they call JavaScript the world's best worst language :D

After I have spruced the Beacon code and finally finished the DocBook DTD with the initial subset, I am going to start the next big task of getting Beacon integrated with Zikula and Publican for a seamless documentation experience.

It looks like Zikula has some text editors and a plug-in for them. I have to find the best way to get Beacon fit in that work flow. Fortunately Beacon already has a feature that allows one to embed it on any page. So it shouldn't be that difficult.

Am still looking for a best way to get Beacon integrated with Publican. It would be nice if the community can suggest a way to do it.

Thursday, July 2, 2009

DocBook Editor 2

Just completed a tiny DTD for DocBook corresponding to the small set of tags for which I had written the XSLs. I am so glad it works! ( works best with firefox)

Now on it is just a matter of adding more elements to get a richer tag-set for DocBook till the mid-term evals. The basic infra is all set up (will try to keep improving usability though).

Also added a brand new and better CSS.

On the other side I think I should try and get more community involvement into developing the editor as the number of DocBook elements is *huge*.

I'll start by explaining what beacon is and how it works.

Beacon is a What you see is what you mean editor which relies heavily on XSL for XML to HTML conversions and vice-versa.

Most of the work involved in making a plugin is writing the two XSLs. One is required for converting the XML to HTML so that it can be displayed in the browser. And the other for converting the HTML back to XML. All these operations are done on the server side using PHP (or Python).

One may wonder, why rewrite XSLs if they already exists, like for Docbook for example. The reason is that Beacon needs some 'hooks' in the generated HTML so it can pick up the nodes using Javascript. This is required to do multitude of tasks like rendering inline editors, maintaining structural sanity, addition/deletion of new nodes, etc. Since HTML and Docbook XML tags are very different, there needs to be some way to map the XML tags over to HTML. These hooks are done using title attribute on tags. So for example, the tag will be rendered in HTML as:

< p title = "docbookPara"> Somethings are best with a title < /p >

Title tags tend to be most unobtrusive here and works well for DOM manipulation which is made even easier thanks to jQuery.

Once the HTML has been rendered, some Javascript magic makes it editable via inline editors of various types. We are still working on the node adding/deleting feature. Once that is done we will have a more or less a complete editor.

The validation of the generated HTML is kept in check via a Javascript based DTD.

So the user cycle of Beacon is:

new document -> XML -> HTML -> XML

All ajax-y communication is handled by JSON (except for file upload which uses an iframe of course).

Since its a web based it relies completely on Ajax for any post first page load. The UI is pretty much like a desktop Application with Tabs, sidebar etc.

To sum it up, a plugin now requires:
  1. Couple of XSLs
  2. Javascript based DTD
  3. Some trivial PHP code
  4. CSS + some template XMLs

I will write a tutorial on how to make a plugin for docbook next. Will be nice if folks chip in to get in as many tags supported as possible.

DocBook Editor 1

It's been very quiet in here. This month has been a marathon of coding and a lot of other events on the home front.

First off, a few non-GSoC related developments:
  • I finished college. (Phew!)
  • I got placed in Red Hat as an Associate Software Engineer. (gleee!)
  • I won the Sun India Code For Freedom contest for my B. Tech Project. (ZOMG!! yes that was COMPLETELY unexpected!)
  • I went out for a small trip this weekend after almost 2 years.
Now to the DocBook Editor...

I started off by learning XSLT (tough!) and making an initial RPM for Beacon and submitted it for review. I created a Feature page and worked on deciding on an initial subset with the help of the Fedora-docs list.

Here are a few links to complement the above:

Then, I constructed an initial XSL by referring to the example DocBook file in the Fedora Documentation repository and based on the initial tag set that was selected after a community review.

Initially, I fixed a few bugs in Beacon to learn the source code and worked on making it more convenient to add plug-ins by changing the implementation so that beacon needs only a DTD from the plug-in makers (which is us) rather than having us code the whole Javascript. A successful implementation of this would save a lot of time in feature addition and creation of plugins.

Apart from the DTD, I was learning the tools more from implementation perspective like JavaScript and jQuery library used in Beacon.

The last week has been the most exciting. Working with Nandeep Mali, the lead Beacon dev and my point of contact for the Beacon upstream, we got the DTD feature implemented to some extent and its working like a charm. The WYSIWYM is also working and just few more additions need to be done to make this a solid XML editor.

The DTD is actually a giant Javascript object which contains details about every node and its structure (like child, parent, siblings). One may think that why not use an existing WYSIWYG editor like TinyMCE. This is not very feasible because WYSIWYG editors are notorious for
the output they produce. This is what Beacon is trying to avoid by adding a different type of editor. The user will be places with a fill-in-the-blanks type of editor so the generated XML will retain its sanity and conform to Docbook DTD. Makes it easy for the Docs team as well.

Now for the treat:

The above URL is a demo of what we have been working with (I hope the Gentoo URL is not a problem. Beacon was a Gentoo SoC project and I cannot get PHP with JSON and XSLs on my fedora account).

The work till now mainly consisted of writing the XSLs for DocBook and making changes to the beacon core. One final enhancement in the usability of beacon would be a drag and drop feature that has not been committed so far as it is very slow at the moment. Once that is ready it will be very easy to add nodes at any point and still not mess up the corresponding XML.

I have been writing the DTD for DocBook since yesterday and will be able to commit it by very soon. So we can expect another blog post about it very soon.

Has been a fun journey so far. More to come in the next post.