The goal is to add expressions support in any of both Data Inputs and Data Outputs declarations.

An expression is given by the following syntax:

#{expression}

This way, the actions to perform are:

• On the UI side
  • For Data Inputs -> Add another dropdown option, in addition to the existing constant one, for expression
  • For Data Outputs -> Add a dropdown option for expression (constant is not allowed for Data Outputs)

• On the marshalling side
  • Once having an expression value, it must NOT be encoded in the resulting XML file, allowing the engine the properly parsing for the expression and further runtime evaluation
  • PS: Nothing has to change in case for constant - value will be encoded as actually it does

Notes:
Engine: https://github.com/kiegroup/kogito-runtimes/pull/314
Example in Eclipse :