As a user I want to be able to define a custom default exception strategy that is used when a a flow or service does not define one explicitly

• User impact:

  Medium
• Effort points:

  3
• Similar Issues:

  None
• Effort:

  S
• % Users Impacted:

  >80%
• Value:

  5

Acceptance Criteria

1. Must be able to redefine default exception strategy for flows and services in a single place.
2. If a flow or service is configured without an explicitly defined exception strategy the custom default exception strategy is used.
3. If there's a global exception strategy configured and no other exception strategy configured then flows / services must use that exception strategy.
   When:

   <mule>
     <configuration defaultExceptionStrategy-ref="dlqExceptionStrategy"/>
   
     <catch-exception-strategy name="dlqExceptionStrategy">
       <jms:outbound-endpoint queue="dlq">
          <jms:transaction action="ALWAYS_BEGIN"/>
       </jms:outbound-endpoint>
     </catch-exception-strategy>
   
   
     <flow name="A">
       ...
     </flow>
   
     <model>
       <service name="B">
         ...
       </service>
     </model>
   </mule>

   Then:

   • flow A uses exception strategy defined in global-exception-strategy
   • service B uses exception strategy defined in global-exception-strategy
4. If there's a global exception strategy configured, an exception strategy configured for a model then services within that model must use exception strategy configured in the model.
   When:

   <mule>
     <configuration defaultExceptionStrategy-ref="dlqExceptionStrategy"/>
   
     <catch-exception-strategy name="dlqExceptionStrategy">
       <jms:outbound-endpoint queue="dlq">
          <jms:transaction action="ALWAYS_BEGIN"/>
       </jms:outbound-endpoint>
     </catch-exception-strategy>
   
     <flow name="A">
       ...
     </flow>
   
     <model>
       <default-exception-strategy>
         ...
       </default-exception-strategy>
   
       <service name="B">
         ...
       </service>
     </model>
   </mule>

   Then:

   • flow A uses exception strategy defined within it
   • service B uses exception strategy defined within model
5. If there's a global exception strategy configured, an exception strategy configured in a model and a service with a configured exception strategy within that model, then for that service the exception strategy to use must be the one defined in the service.
   When:

   <mule>
     <configuration defaultExceptionStrategy-ref="dlqExceptionStrategy"/>
   
     <catch-exception-strategy name="dlqExceptionStrategy">
       <jms:outbound-endpoint queue="dlq">
          <jms:transaction action="ALWAYS_BEGIN"/>
       </jms:outbound-endpoint>
     </catch-exception-strategy>
   
     <flow name="A">
       ...
       <default-exception-strategy>
         ...
       </default-exception-strategy>
     </flow>
   
     <flow name="B">
       ...
     </flow>
   
     <model>
       <default-exception-strategy>
         ...
       </default-exception-strategy>
   
       <service name="C">
         ...
         <default-exception-strategy>
            ...
         </default-exception-strategy>
       </service>
   
       <service name="D">
         ...
       </service>
     </model>
   </mule>

   Then:

   • flow A uses exception strategy defined within it
   • flow B uses global exception strategy
   • service C uses exception strategy defined within it
   • service D uses exception strategy defined within model