[rules-users] Rule one-by-one comparison

Swindells, Thomas TSwindells at nds.com
Fri Aug 26 12:02:04 EDT 2011


xPath is also a pretty powerful solution, have one xPath that fines the rule node, then against that node run a pair of xpath expression which extract the agenda-group value and the literal restriction value(s).

Thomas

From: rules-users-bounces at lists.jboss.org [mailto:rules-users-bounces at lists.jboss.org] On Behalf Of Wolfgang Laun
Sent: 26 August 2011 16:58
To: Rules Users List
Subject: Re: [rules-users] Rule one-by-one comparison

Perhaps you consider using JAXB for creating Java classes from the XML schema, which lets you unmarshall the XML file into an object tree which is easy to traverse and provides you with all the data as objects and lists; no string parsing at all.

-W

2011/8/26 miguel machado <mls.machado at gmail.com<mailto:mls.machado at gmail.com>>
Hi there,

I'm considering analyzing the pre-compiled xml document as a "last resort": I actually find it easier to deal with objects/collections/arrays than with Strings and XML, etc. This is a personal stance with no much foundation regarding this specific drools scenario, really.

What I need to do (before the actual comparison) is to group the rules according to the agenda-group plus a variable value within a condition within every <rule>, such as this:

<rule>
  ...
  <rule-attribute name="agenda-group" value="0da90b15" />
  ...
  <field-constraint field-name="object">
    <literal-restriction evaluator="==" value="d:" /> <!-- LiteralConstraint java object -->
  </field-constraint>
  ...
</rule>

(in this case I'd like to index this rule to a 2-key hashmap => [0da90b15, "d:"])

XML manipulation would mean parsing hundreds of rules, extracting the agenda-group and the "object" condition manually. Further down the road, I will also need to extract the whole LHS to perform the comparison. I'm afraid this would take too long, but I might be wrong.

Thanks again,
_ miguel, PT



2011/8/26 Swindells, Thomas <TSwindells at nds.com<mailto:TSwindells at nds.com>>
Wouldn't it be easier to analyze the pre-converted xml document rather than trying to do it on the compiled knowledge base (presumably you keep the old xml file around) - this way it is just string and xml manipulation, though it depends on how exactly the matches must be.

Thomas

From: rules-users-bounces at lists.jboss.org<mailto:rules-users-bounces at lists.jboss.org> [mailto:rules-users-bounces at lists.jboss.org<mailto:rules-users-bounces at lists.jboss.org>] On Behalf Of miguel machado
Sent: 26 August 2011 15:55

To: Rules Users List
Subject: Re: [rules-users] Rule one-by-one comparison

Hi there,

Thanks for replying. I will try to explain my current challenge a bit further:

I have a ruleset which is sent by an external application in XML format. I load it to a new knowledge package and then into a knowlegde base. It is made of smaller subsets of 3 rules each (a "set" rule, a "reset" rule and a "clear" rule) that control my application's internal logic, which must be stateful and kept on disk (basically, there are 2 important hashmaps).

Whenever the rules change, a new XML ruleset is sent and my application restarts and loads the new file the exact same way. However, I need to resume the application state (as it was before the restart). I also have to do this selectively, because I only care about the application state on a per-rule basis:

- If a rule keeps the same LHS, I need to resume the application state before restart regarding that rule;
- If a rule has been modified, I may discard the state regarding that rule (do not need to load it);

I don't think I can refactor this problem into smaller ones, the application internal logic is indeed complex I'm afraid. The rules are analyzed in a stateless way BUT they control a set of critical information which must be stateful (beyond restarts). There is a (not-so-direct) correspondence between each (fire, reset, clear) rule subset and the information that keeps track of the internal state, so that's why I need to verify rule-by-rule what has changed between restarts.

I hope this helps to describe the problem.
Thanks again for reading. Any help is greatly appreciated.

_ miguel, PT





2011/8/26 Swindells, Thomas <TSwindells at nds.com<mailto:TSwindells at nds.com>>
Can you share what you actual requirement is and why you need to do it?
Can you perhaps change the problem into one that is simpler to solve?
Ie rather than comparing knowledge bases can you get the input to these knowledgebases?
Can you control what that input is, if it is a DSL or a spreadsheet then your comparision job will probably become a lot simpler.

Thomas

From: rules-users-bounces at lists.jboss.org<mailto:rules-users-bounces at lists.jboss.org> [mailto:rules-users-bounces at lists.jboss.org<mailto:rules-users-bounces at lists.jboss.org>] On Behalf Of miguel machado
Sent: 26 August 2011 13:01
To: Rules Users List
Subject: Re: [rules-users] Rule one-by-one comparison

Esteban,

Thank you very much for that. I will look into it.
Any other ideas, anyone?

_ miguel



2011/8/26 Esteban Aliverti <esteban.aliverti at gmail.com<mailto:esteban.aliverti at gmail.com>>
You can try to use drools-verifier. This project basically lets you define rules about your rules.
You can have a look at its tests to see how it works.
You can get more info about drools-verifier here: http://community.jboss.org/wiki/DroolsVerifier

And here you can see how are we using drools-verifier inside Guvnor: http://ilesteban.wordpress.com/2010/04/05/guvnors-field-constraints/

Best Regards,

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Esteban Aliverti
- Developer @ http://www.plugtree.com
- Blog @ http://ilesteban.wordpress.com
2011/8/26 miguel machado <mls.machado at gmail.com<mailto:mls.machado at gmail.com>>
Hi there everybody,

I need to perform rule comparison on a project I'm working on using drools expert 5.0. For a specific feature implementation, I have two different knowledge bases with several rules which I need to compare, one by one. By comparing, I mean "inspect" certain conditions within the LHS.

Currently, I'm able to obtain several attributes from rules (org.drools.rule.Rule), such as the agenda-group and the rule name and a few others, but I haven't been able to do it all. Going deeper, there is LiteralConstraint (for simple conditions) which I can parse and obtain data. However, I don't know how to do it for OR-conditions, which I guess represents a MultiRestrictionFieldConstraint. Perhaps there is another way?

I know this may seem like a very unorthodox thing to do, but I don't think there is a better way of comparing knowledge packages (except for full text comparison). Is there?

Thanks in advance,
_ miguel, PT


--
"To understand what is recursion you must first understand recursion"


_______________________________________________
rules-users mailing list
rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
https://lists.jboss.org/mailman/listinfo/rules-users


_______________________________________________
rules-users mailing list
rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
https://lists.jboss.org/mailman/listinfo/rules-users



--
"To understand what is recursion you must first understand recursion"


________________________________

**************************************************************************************
This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster at nds.com<mailto:postmaster at nds.com> and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do not print this e-mail unless necessary.

NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00
**************************************************************************************

_______________________________________________
rules-users mailing list
rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
https://lists.jboss.org/mailman/listinfo/rules-users



--
"To understand what is recursion you must first understand recursion"


_______________________________________________
rules-users mailing list
rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
https://lists.jboss.org/mailman/listinfo/rules-users



--
"To understand what is recursion you must first understand recursion"


_______________________________________________
rules-users mailing list
rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
https://lists.jboss.org/mailman/listinfo/rules-users

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20110826/2f66b194/attachment.html 


More information about the rules-users mailing list