Why don't you define two databases in your own DbHelper:
<drools:endpoint service="test:service"
endpoint="endpoint"
ruleBaseResource="classpath:router.drl"
globals="#globals" />
<util:map id="globals">
<entry key="helper" value-ref="helper" />
</util:map>
<bean id="helper" class="DbHelper" />
<bean id="ds1" class="org.springframework.jndi.JndiObjectFactoryBean">
<property name="jndiName" value="java:ds1" />
</bean>
<bean id="ds2" class="org.springframework.jndi.JndiObjectFactoryBean">
<property name="jndiName" value="java:ds2" />
</bean>
</bean>
Then in your drools rules:
package org.apache.servicemix.drools
global DbHelper helper;
global DataSource ds1;
global DataSource ds2;
rule "Rule1"
when
eval( db.exist( in.valueOf("/ACTION/@name"), "STRING", "attribute",
"name", ds1 ) );
That way, you just need to patch the DbHelper so that it can take an
optional argument which is a dataSource
instead of using the one that is configured on the DbHelper.
It should be possible to include such a patch.
On Jan 30, 2008 9:04 AM, Andrea Zoppello <[EMAIL PROTECTED]> wrote:
> Hi.
>
> I don't understand quite well this approach. Could you provide an
> example please.
>
> But it could be more useful, to inject in dbhelper an object that give
> me the access to
> JNID tree of servicemix.
>
> Is there a way to do this, now in my customized version od DroolsHelper
> i get the context and
> i pass to dbhelper as follow.
>
> protected void populateWorkingMemory(WorkingMemory memory,
> MessageExchange exchange) throws Exception {
> memory.setGlobal("jbi", new JbiHelper(this, exchange, memory));
> EndpointComponentContext aContext =
> (EndpointComponentContext)getContext();
> InitialContext jndiContext = aContext.getNamingContext();
> memory.assertObject(new DbHelper(jndiContext));
> }
>
> What i need is only a way to inject such object in spring xbean file.
>
> Is this possible??
>
>
>
>
> rgavlin ha scritto:
>
> > Hi,
> >
> > How about using xbean/spring as in the referenced blog to populate the
> > Drools globals map with key/value pairs, the key being the datasource name
> > and the value begin a DbHelper instance that wraps the corresponding
> > datasource instance? In the drools file, one can reference the desired
> > DbHelper by datasource name key. Using this technique, there should be no
> > need to package the DbHelper class within the Drools SE component.
> >
> > - Ron
> >
> >
> > Andrea Zoppello-2 wrote:
> >
> >> Hi all,
> >>
> >> I need to use drools servicemix component, and in my rules, i need to
> >> use a db helper object to
> >> evaluate some rule conditions against database.
> >>
> >> I've just read the very good approach, proposed in
> >> http://gnodet.blogspot.com/2007/06/accessing-databases-in-servicemix.html.
> >>
> >> The only problem, that i've with this approach is that some of my
> >> customer, want to have in
> >> the dbhelper methods, a parameter that switch the datasource to use for
> >> a query:
> >>
> >> for example they want to write something like:
> >>
> >>
> >> package org.apache.servicemix.drools
> >>
> >> import org.apache.servicemix.drools.model.Exchange;
> >> import org.apache.servicemix.drools.model.DbHelper;
> >> global org.apache.servicemix.drools.model.JbiHelper jbi;
> >>
> >> rule "Rule1"
> >> when
> >> me : Exchange( status == Exchange.ACTIVE, in : in != null );
> >> db : DbHelper ( );
> >> eval( db.exist( in.valueOf("/ACTION/@name"), "STRING",
> >> "attribute", "name", "ds1" ) );
> >> then
> >> jbi.fault( "<ERROR> The value is already present in db </ERROR>"
> >> );
> >> end
> >>
> >> rule "Rule1"
> >> when
> >> me : Exchange( status == Exchange.ACTIVE, in : in != null );
> >> db : DbHelper ( );
> >> eval( db.exist( in.valueOf("/ACTION/@name"), "STRING",
> >> "attribute", "name", "ds2" ) );
> >> then
> >> jbi.fault( "<ERROR> The value is already present in db </ERROR>"
> >> );
> >> end
> >>
> >> where the last parameter of db.exist method identidies the datasource
> >> and they could have rules that
> >> switch from ds1 to ds2.
> >>
> >> To do this it could be enough to have an object that let's my helper to
> >> access the jndi context of servicemix.
> >>
> >> To get this type of behaviour at the moment, we've a customized version
> >> of servicemix-drools, but
> >> in future i'd like to rely on the standard component.
> >>
> >> Is this possible to achieve this, maybe injectiong in a helper object
> >> that lets me to access to jndi of servicemix???
> >>
> >>
> >> Thanks in advance
> >>
> >>
> >> Andrea
> >>
> >>
> >>
> >>
> >>
> >
> >
>
>
--
Cheers,
Guillaume Nodet
------------------------
Blog: http://gnodet.blogspot.com/
