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  1. camunda BPM
  2. CAM-13637

Support JUEL delegate expressions in Quarkus



    • Feature Request
    • Resolution: Unresolved
    • L3 - Default
    • None
    • None
    • quarkus
    • None


      User Story (Required on creation):

      As a user, in modeling resources (e.g., on sequence flows), I can define expressions that call methods on a bean.

      Functional Requirements (Required before implementation):

      E.g., in a sequence flow camunda:expression attribute, I can use the following expression:

      Technical Requirements (Required before implementation):

      Quarkus ArC does not support the API method BeanManager#getELResolver. Replace it with something else.

      Limitations of Scope (Optional):

      Hints (Optional):

      Right now, only a simple JUEL expression referencing a delegate bean directly can be resolved: ${myDelegateBean}. Referencing a delegate bean via a more complex expression is not possible ${myBean.getDelegateBean()} due to missing support in Quarkus ArC of BeanManager#getELResolver. Let's evaluate if and how we can fix this.

      Solution ideas

      1. Shade de.odysseus.juel into the Quarkus extension like we already do it in the legacy JUEL FEEL Engine.
        • Or even cleaner: create a shaded jar containing de.odysseus.juel the DMN legacy FEEL Engine, as well as Quarkus, uses.
        • Identify Quarkus environment by catching the UnsupportedOperationException when BeanManager#getELResolver is called in CdiResolver#getWrappedResolver.
        • Register the javax.el.BeanELResolver instead.
          • Tries to create a ExpressionFactory by looking up the SPI.
        • Register an ExpressionFactory SPI in the Qurkus extension pointing to de.odysseus.el.ExpressionFactoryImpl.
        • See prototypical implementation (shading is missing): fix-quarkus-el-support.patch.txt
      2. Wait until Quarkus supports BeanManager#getELResolver


        This is the controller panel for Smart Panels app


          Issue Links



                Unassigned Unassigned
                tassilo.weidner Tassilo Weidner
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