RPC cancellation

[Rosa Lisin]

Hi Emile,

Could you please provide some guidance on remote procedure call cancellation usage?  How can the following call be cancelled:

auto result= session->call(Rpc("some_long_call"), yield);

It seems that in order to cancel an RPC one needs to know the request Id, but request id seems to be available only when that call returns since it is a member of the Result class.

Thanks a lot,

Rosa Lisin

[Emile Cormier]

Hi Rosa,

You need to use the Session::call overload, which is asynchronous and immediately returns a RequestId: https://github.com/ecorm/cppwamp/blob/310278b74c3413c8cc44c60adc6feb777d651dca/cppwamp/include/cppwamp/session.hpp#L207

CoroSession derives from Session, so you have access to the async API if you need it from a CoroSession instance.

You'll need to provide an asynchronous handler routine, within which you can spawn a new coroutine if needed.

There's an example of call cancellation in the unit tests here: https://github.com/ecorm/cppwamp/blob/310278b74c3413c8cc44c60adc6feb777d651dca/test/wamptestadvanced.cpp#L409

I'm sorry that there's no tutorial example of call cancellation at this point. Hopefully you can figure it out from the unit test example.

Cheers,

Emile

[Rosa Lisin]

Thanks, Emille,

I will try to figure it out. 

Best regards,

Rosa