Drools Flow, threads and persistence in a clustered environment
by Alexandros Karypidis
Hello,
We plan to use Drools (Flow) in our application for managing
long-running processes. High-availability is important to us and
therefore we target a clustered JBoss environment with 3 nodes. We are
looking for advice on how to approach this from a Drools perspective.
Can anybody share their experiences on running Drools in a cluster? The
following scenarios come to mind:
1) A "singleton" ksession runs constantly on one of the nodes and does
all the work; it migrates when the node goes down to another machine.
2) Multiple "ksession" instances on different nodes (for distributing
load); when one fails the other picks up its processes by having a
second "ksession" instance created on it and resuming execution.
Are there any wrapper/utility libraries for Drools that help in
clustered environments?
Thank you
16 years, 5 months
DSLR Editor: Context Assist + Enter deletes the who line? Is is broken??
by mehdi bennani
Hi guys,
I have been using drools 4 for couple of months now and I am starting to get the hang of it. We recently decided to move to Dools 5 with Eclipse 3.4.2 (Ganymede).
We unfortunately hit a major 'show stopper' (for us). In the DSLR editor: Context Assist + space + enter removes/replaces the whole line, not only the place holder.
In other words:
DSL:
[*][]Log : {msg}=System.out.println("{msg}");
[*][]id1="some id label"
DSLR:
rule "MyRule"
when
then
end
If I Press L , control space --> the line Log:{msg} appears in the context menu. Hit enter I get
Log :{msg}
Now, If want to replace msg by id1. I position the cursor in the {msg}, hit ctrl space, id1 shows in the list. I hit enter the whole line disappear, and I am left with
id1
instead of
Log : id1
Is this a setting somewhere in eclipse itself?? I doubt it.
The same thing use to work as expected in Drools 4.
thanks.
/elextra
16 years, 5 months
adding constraints in DSL
by Chandana Pingle
Hi,
i need to add multiple constraints on the same field
example
There is a Cheese with
- age is less than 42 or age is more than 60
- age is not in ("20" ," 30", "40")
how can i write this in DRL and DSL?
Thanks
chandana
16 years, 5 months
Drools Fusion aggregate functions
by PF
Hi,
Does Drools Fusion provides any kind of aggregate functions over events
(count, sum, etc.) or these should be created as rules with intermediate
results exchanged through the database (inserted and delated facts)?
Regards,
Paul Fodor.
16 years, 5 months
Re: [rules-users] For each - properties
by Bill Tarr
Betto,
I just went down this road with ForEach in DroolsFlow. The documentation on those properties was a little lacking in my opinion.
CollectionExpression = should be an expression that resolves to a java.util.Collection. So a Person has a List<Loans>, and your flow has a variable person which you set, the expression could be:
person.loans
VariableName = is the name given to the current item you are passing in. Perhaps just loan. That is the variable that will be passed into your subflow (or RuleGroup in your case.)
I did a similar thing with for a demo, but ran into another problem. I called a Subflow from within the ForEach, and passed in my variable (lets say loan.) I could access the variable easily enough in Actions, using code - like
loan.getStatus().equals("Approved")
but have not been able to get a RULE to execute against that variable. Like
$loan : Loan (status == "Approved")
Not sure what the problem was with my code, but will revisit later.
I bring that up in case you run into it because you are just calling a rule within your ForEach. Maybe try a simple code action first, something like
System.out.println(loan.getStatus());
Anyway, let me know how it goes. Kind of nice to see someone going down the same road...
Bill
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
16 years, 5 months
How to avoid hardcoded URL in the ChangeSet resource XML file?
by Blythe, Marshall
Is there any way to avoid using hardcoded URLs in the ChangeSet resource XML file? I'd like to be able to parameterize that bit of data and substitute the actual value at runtime. For example, something like this would be nice:
<change-set xmlns='http://drools.org/drools-5.0/change-set'
xmlns:xs='http://www.w3.org/2001/XMLSchema-instance'
xs:schemaLocation='http://drools.org/drools-5.0/change-set.xsd'>
<add>
<resource source='${rules.url}' type='DRL' />
</add>
</change-set>
${rules.url} would be read from a resource bundle (i.e. property file) at runtime. Is there some extension point that I can use to implement this behavior?
----------------------------------------- This e-mail and any attachments may contain CONFIDENTIAL information, including PROTECTED HEALTH INFORMATION. If you are not the intended recipient, any use or disclosure of this information is STRICTLY PROHIBITED; you are requested to delete this e-mail and any attachments, notify the sender immediately, and notify the LabCorp Privacy Officer at privacyofficer(a)labcorp.com or call (877) 23-HIPAA.
16 years, 5 months
[DroosFlow] Restore the StatefulKnowledgeSession
by Anderson vasconcelos
Hi
I'm have a flow with two moments. First the *client* created the task.
Second the *user* approve the task. The Second can occurred in another
day, year, month. Has one way to persist the StatefulKnowledgeSession in
database and recuperated them again?
This is necessary:
1) Because my Application Server can crash and i need to recuperated my
session
2) Because i need to update the facts after *user* approve task
Thanks
16 years, 5 months
Conversion from Normal Decision Tables to Web-Based Tables and vice-versa
by Vikrant Yagnick
Hi All,
I am wondering if anyone has had a requirement where they would need to convert their normal decision tables into web-based decision tables(or vice-versa).
If someone has already done this, can they share either some code or pointers to how this can be done? (I guess it will involving parsing the Excel and creating the XML for the decision table).
Will this be a useful feature to have?
Cheers,
Vikrant
MASTEK LTD.
Mastek is in NASSCOM's 'India Top 20' Software Service Exporters List.
In the US, we're called MAJESCOMASTEK
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Opinions expressed in this e-mail are those of the individual and not that of Mastek Limited, unless specifically indicated to that effect. Mastek Limited does not accept any responsibility or liability for it. This e-mail and attachments (if any) transmitted with it are confidential and/or privileged and solely for the use of the intended person or entity to which it is addressed. Any review, re-transmission, dissemination or other use of or taking of any action in reliance upon this information by persons or entities other than the intended recipient is prohibited. This e-mail and its attachments have been scanned for the presence of computer viruses. It is the responsibility of the recipient to run the virus check on e-mails and attachments before opening them. If you have received this e-mail in error, kindly delete this e-mail from desktop and server.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
16 years, 5 months
Mail System Error - Returned Mail
by Mail Delivery Subsystem
The original message was received at Mon, 5 Oct 2009 06:09:22 +0200 from 136.108.8.185
----- The following addresses had permanent fatal errors -----
<rules-users(a)lists.jboss.org>
16 years, 5 months
