[SoC] SoC report: Geo-BI dashboards

[Etienne Dube]

Hi everybody,

1. What did I do this week:

- Continued work on OLAP navigation operators (let's call them navops). 
I had some feedback from Julian Hyde (lead developer of Mondrian and 
olap4j) on the olap4j forums (see 
http://sourceforge.net/forum/forum.php?thread_id=2081316&forum_id=577988 
) and started the implementation of query transformations following his 
proposal for an interface. However, most of the needed MDX query 
transformations for OLAP navigation operators are very complex to 
implement. After discussion with my mentor, I've chosen to write a 
limited subset of these, mainly a simple drill by replacement which 
handles a single dimension on an axis, and a simple roll-up by level 
(also handling a single dim by axis). The interface for generic MDX 
query transforms is cleanly defined though, so more complex OLAP 
transforms will be added at a later time (maybe after the end of the 
GSoC timeframe) and could be integrated to the core GeoBI servlet with 
minimal modifications. Since these MDX query transforms could be useful 
for a large number OLAP applications based on the olap4j API, I will 
contribute the new org.olap4j.transform experimental package to the 
olap4j trunk, once I had time to clean and document the code a little 
bit ;) .

- Started the needed work to handle these navops in the servlet and web 
client (feature selection and click handling with OpenLayers, created a 
Dojo toolbar for selecting the navop to apply, added new parameters to 
the request passed to the servlet, ...). Basic drill-down functionality 
is almost there!

2. What do I plan on doing next week:

- Continue working on navops and their use in the OLAP web mapping 
client/servlet.

3. Am I blocked on anything:

- No, I just hopped past quite a major block. There's still a lot of 
work to do on OLAP navops and query transforms, but for the moment what 
I coded will be sufficient to continue my work on the OLAP web mapping 
component.

Have a nice weekend,

Etienne