ISSUE 21 - Clarify Request Scope lifetime

RAISER: Michael Rowley

TARGET: SCA Java Component Implementation Specification section titled “Request Scope”

DESCRIPTION:

The section currently starts with the following sentence:

“The lifecycle of request scope extends from the point a request on a remotable interface enters the SCA runtime and a thread processes that request until the thread completes synchronously processing the request.”

From this description, it is not clear whether the request scope lasts through a remotable call to another component that happens to be local. In one possible interpretation it would depend on the binding. A call through a web service binding would be seen as changing threads, and therefore would be a new request scope. The same call through an SCA binding might be assumed to remain within the thread and therefore be within the same scope.

It is probably a bad idea for the scope to depend on the binding that is used, and it may even be a bad idea for the scope to depend on whether a call through a remotable interface _happens_ to be local.

PROPOSALS:

1) Have the request scope be only for a single remotable operation call. From that operation, any request scope component that is reached through only local-service calls would reach the same component instance. Calls through a remotable interface would introduce a new request scope.

2) Alternately, the request scope could last from the time a request “enters the SCA runtime” until it is done, but with the clarification that the “SCA Runtime” is domain-wide. As long as a call is made to another SCA component within the same domain (irrespective of the binding used) it is part of the same request scope.

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