Exception policy for handling request, notification and message. #21
Description
Current state of exception handling is:
- When handling a request, forward exception to requester and go on.
- When handling a notification and a message, follow akka exception policy (ask a parent to what to do)
The reason that request handling have a different exception policy is that it follows the RPC model and exception need to be propagated to caller. (not parent) But this inconsistency is not good to keep and sometimes a critical exception in handling a request requires parent to do something. It seems reasonable to change policy like following.
- When handlig a [request | notification | message], follow akka exception policy.
- There might be an option to make some kinds of exception propagated to a caller not a parent.
- Whenever an exception is raised in handling a request, a caller should get exception response to prevent a request timeout.