RE: Drools and CAM

[<martin.me.roberts@bt.com>]

Hi,
 
 In JCAM I have built in a mechanism to have DROOLS perform the DataValidation section of the CAM Spec.  The idea is that by passing in a set of nodes described by an XPath it would be posible to invoke a script that would then work with the nodes supplied.
This is done by describing a Java Class that allows the nodes to be added to the DROOLS working memory and allow the consequences to interact with the nodes by changing values etc.
It seems to work reasonably well and is very simple to implement.
 
I am also toying with the idea of using the DROOLS ApplicationData construct to allow the rules engine to be passed the either the template or the xmlfile.  This would enable DROOLS to manipulate the complete tree and possibly transform the output based on the rules.  The other extension would be to allow the DROOLS to be passed an empty document that it could use to hang new constructs off based on the rules firing.
 
One of the questions I have is what rules might be applied.  Without some clear examples it if not easy to know how to integrate the tool.  It seems to me that DROOLS could be used in two parts of the CAM template - DataValidations and External Mappings.
 
One further thing I am investigating for jCAM is the use of PicoContainer as a method to allow the other processors to be included into the processor.  The idea being that for each section of the CAM template a processor would be passed three possible things - the XML file being processed, the Assembly Structure after the Business Rules hade been applied and the section of the CAM template the applied to the processor being plugin.  The advantage of this method is that we can get the whole of the CAM Spec done by different people yet all work with the same tool.  It also means that somebody can change the default processor with another without affecting the other bits.  For example if I get the split right we should be able to allow schema based includes without disrupting the rest of the tool.
 
Happy New Year
 
Martin

________________________________

From: Mark Proctor [mailto:mproctor@codehaus.org]
Sent: Mon 02/01/2006 05:46
To: David RR Webber (XML)
Cc: TANVEER_ASHIQUE@bah.com; CAM TC; Roberts,MME,Martin,XBX R
Subject: Re: Drools and CAM


Sure no problem, we are always there - just letting you know, in case you need any help with Drools.

Mark
David RR Webber (XML) wrote: 

	Mark,
	 
	We'll see who it goes.  My time is extremely short this week - will attend to the PPT first.  Maybe some of the other folks on the list may want to hop over for a chat....
	 
	Thanks, DW
	
	


		-------- Original Message --------
		Subject: Re: Drools and CAM
		From: Mark Proctor <mproctor@codehaus.org> <mailto:mproctor@codehaus.org> 
		Date: Sun, January 01, 2006 10:38 pm
		To: "David Webber (XML)" <david@drrw.info> <mailto:david@drrw.info> 
		Cc: TANVEER_ASHIQUE@bah.com, CAM TC <cam@lists.oasis-open.org> <mailto:cam@lists.oasis-open.org> , Martin
		Roberts <martin.me.roberts@bt.com> <mailto:martin.me.roberts@bt.com> 
		
		IRC isn't a list it's a live chat room where you can talk to me and the other developers - no need to subscribe, just pop in and have a chat :)
		
		Mark
		David Webber (XML) wrote: 

			Mark,
			
			Your PPT is a great introduction to the world of rule engines and
			methods.
			
			My own background is heavily Prolog - for 15 years.  I missed seeing
			constraint based solutioning - but I guess DROOLS has to leave
			somethings to
			those old purpose built engines!  And besides DROOLS could always
			collaborate with a Prolog engine as a close cousin.... ; -)
			
			On to CAM and DROOLS.  I have some PPT slides I will share during the
			week
			once I've cleaned them up for external perusal.
			
			Basically the notion is to use the mechanisms in CAM - that is
			essentially a
			domain expert agent in XML structures and metadata - and provide an
			interface directly in CAM to DROOLS and back again.  Then we're adding
			the
			ability to persist to SQL databases in CAM directly from the XML source
			-
			using simple XML syntax based assignment instructions.
			
			This should allow people who are not DROOLS experts - to create a
			business-centric solution that quickly handles basic ebusiness
			transactions - while allowing extended rules to be layered into this -
			by
			software staff - that handle decreet rules and tests that are beyond the
			scope of the base CAM function set.
			
			This gives people the best of both worlds - a purpose built business XML
			expert agent - coupled to the extensible DROOLS engine.
			
			Your snippet of DROOLS V3 shows that this is all heading in the right
			direction.
			
			We've been experimenting with:
			 <as:includeScript location="{url/my.drl}"/>
			and
			<as:executeScript name="{name.drl}" parm="\\xpath\locator\*"/>
			
			as a first pass to provide linkage between the two.
			
			I am definately interested in discussing this with the DROOLS community
			-
			where CAM can provide a pluggable XML handler toolkit for DROOLS users?
			
			Beyond all this - DROOLS also looks like a good means to implement a
			state
			machine for BPSS (and JBOSS driven BPM) as envisioned in our BCM
			architecture work - but we'll solve one problem at a time here!
			
			I'm a bit allergic to signing up for IRC lists - my daily bandwidth is
			severally constrained already - but we can definately look at sharing
			some
			collaboration resources - possibly a wiki area - where ideas and test
			components can be posted..?
			
			Thanks, DW
			
			----- Original Message ----- 
			From: "Mark Proctor" <mproctor@codehaus.org> <mailto:mproctor@codehaus.org> 
			To: <david@drrw.info> <mailto:david@drrw.info> ; <TANVEER_ASHIQUE@bah.com> <mailto:TANVEER_ASHIQUE@bah.com> 
			Sent: Sunday, January 01, 2006 2:24 PM
			Subject: Drools and CAM
			
			
			  

				David, Tanveer,
				
				GoogleAlert brought your postings to my attention. We have big plans for
				Drools 3.0, which will be available at the end of Q1 - see the slides at
				
				    

			http://drools.org/download/attachments/20545/Business+Rules+Engines.ppt?version=1
			  

				for more details.
				
				In the mean time if there is anything more we can do to assist or you
				just want a general chat, we are always on the irc server #drools at
				irc.codehaus.org - we provide a web gateway at http://irc.codehaus.org <http://irc.codehaus.org/> 
				if you do not want to install an IRC client.
				
				Mark