[Overflow] Re: DL and PL integration

[Brad C. <cha...@ar...>]

jarl wrote:
>  This will change the old plan of linking the PL and BL to one binairy.
>  There's no real prob as long as we setup a good authentication
meganism
>   between the 2 layers.

Well, basically I guess I was just thinking about the CORBA layer only
being sort of between node communication from the PL to the BL. The
reason I think this is a good idea, is so that nodes can be written in
languages other than C++. I am really into this, since I think it will
help us use nodes from other projects (like ISYS and ALBeanBox) although
I'm not sure how yet :-).


[having id numbers that the BL would have to keep track of]
>  This we already have, the Universal Resource Id (URI), look @ the
>  DL-BL idl.

Right, although I'm not sure I understand how this will hook in with the
way Overflow uses unique 'names' as id for nodes. Have you already coded
this in the BL? Sorry, I am waaaaay behind on where the BL code is at
:-<.
 
I wrote:
>  > 2. How can the stream class return the stop or continue messages
> >  back to the node? I'm not sure how we can achieve this kind of
callback
> >  with the stream setup, but this is probably just me missing
something.

Jarl wrote:
>  I dont quite see what you're pointing at, can you explain a bit more?

Well, what I was thinking of is this:

-> The node registers some kind of error. It pauses the run because of
the error and then calls the error stream.

errorStream << 1 << 'some kind of error';

-> The error stream recieves the error. It creates a PlErrorCallback and
calls the BL with an error message.

-> The BL recieves the error message, passing it on to the DL and then
the UI, where the user decides to continue the run.

-> The BL gets this message and calls runContinue() on the
PlErrorCallback.

-> Now my big question mark -- how does this info get back to the node so
it knows to keep processing getOutputs()? Am I misunderstanding the
design here?

Brad

Does this make sense?