[rules-users] Advice on varying rule behavior based on object tested?

[zstlaw]

Each item I am testing MAY have overridden the default thresholds or disable
the rule entirely.  I would prefer to have this data related to the item I
am testing rather than have each rule manage customized behavior for
thousands of different types of objects.  

The object could have a map of rule thresholds it overrides, but for
simplicity I assume there is a method to return the current threshold for
the current object.  is there a better way to perform this kind of logic? 
Example of my current code:

declare TestedEntity
    temp : Double
end

declare AlertThreshold
    maxAllowed : Double
end

rule "Check temperature"
    when
        $entity : TestedEntity( )
        // would prefer to use drools.getRule().getName() on next line
        AlertThreshold($entity.temp > maxAllowed)  from
$entity.getAlertThresholdForRule("Check temperature")
    then
        // raise alert
end

I dislike hard-coding the rule name as it leads to copy paste errors.  I
can't insert thresholds easily unless I define different ones for each rule
and I want to be able to fall back to defaults easily.  This is a type of
problem I have come up against several times now so I feel like others must
have dealt with it before.  The idea of writing copies of rules tailored to
each Entity appeals less than a generalized way of doing this.  By doing
this I want to contain complexity.  Dozens of slightly different
implementations of the same rule would be much harder to test and support. 
I am dealing with hundreds of thousands of facts today and will need to
scale to millions before I can deploy fully.  But with that large number I
need to have ways to manage exceptions to the general case just to keep
complexity manageable.

Thanks,
Zack

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