Incoming messages are delegated through a chain of correlation logic to route messages to the proper response message. The multi-layered approach to correlating incoming messages to response messages provides flexibility and power in modeling dynamic and realistic virtual assets that behave in the same way as the real assets— and do so in a manner than scales well.

When an incoming message is received, the following occurs:

  1. Virtual asset selection: A deployed virtual asset is selected to respond to the message based on the HTTP path, JMS/MQ queue names, or other extension/custom criteria that is configured in each virtual asset configuration. A virtual asset corresponds to a .pva, so this step effectively determines which .pva file will be used to respond to that message. If no virtual asset is found to respond to that message, then an error message is returned to the requester. If two virtual assets are deployed on the same HTTP path, Virtualize will choose one that has a responder with matching correlation criteria.
  2. Responder selection: A responder is selected among the responders in the responder suite of the virtual asset’s .pva file. Responders are evaluated sequentially, in a depth-first search pattern within the virtual asset. Once a Responder Correlation criteria matches the incoming message (see Responder Correlation Tab), this responder will be used to respond to the message and the correlation moves on to the next step.
  3. Response: The response is built and populated using data source correlations.