Hi Guys, Just exploring Flowable. Started playing with modeler but couldn’t figure out a way to use conditions for rules. Any thoughts?
Thanks for your time.
Hi Guys, Just exploring Flowable. Started playing with modeler but couldn’t figure out a way to use conditions for rules. Any thoughts?
Thanks for your time.
Hi,
A good place to get started is the docs (http://www.flowable.org/docs/userguide-dmn/index.html#whatIsDmn).
But the Flowable DMN editor is supporting JUEL for expressions. So any JUEL expression that evaluates to a boolean can be used in a rule. But you can also use the simple input conditions without JUEL expressions with for example a < 40 condition for a number variable.
Best regards,
Tijs
@tijs Thanks for your reply.
I understand JUEL is supported but not sure how it can be modelled on Modeller though. Not sure if operations dropdown (please see attachment ) is relevant when using JUEL. Any thoughts?
Hi,
Ok. When you defined a JUEL expression like ${test == ‘test’} in the cell then the operator and even the variable name in the input column are ignored. So the JUEL expression like it is filled in will be executed as-is.
Best regards,
Tijs
Understood now @tijs. Thanks.
I think we should “expression” as data type and hide operators when it chosen. Is GitHub is the right place create this feature request?
I wasn’t fully complete about this. Defining a full JUEL expression is optional, and you can also use it to define the expression after the input variable name and operator. Only if the rule starts with ${ the rule is taken as-is. If the rule is define like:
== "Pass" && inputVar > 1
Then this will be transformed to a JUEL expression like:
${test == "Pass" && inputVar > 1}
So in this case the operator is still used. So the logic should check if the rule starts with ${ or #{ and then the operator should be disabled.
Yes Github is the right place to add a feature request.
Best regards,
Tijs
Thanks @tijs. Very much appreciate it.
Sorry, just one last question on this. Any idea how can we validate DMN JUEL expressions for syntax errors?
Hi,
Good point, that’s not so easy :-). The only possibility I can think of is to really execute the JUEL expression with an example variable value that the user provides.
Best regards,
Tijs