| [corona-dev] Container and Collaboration Evenets |
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The support of Collaboration Events between containers is an
important feature. When we talked this morning we thought we would have
subcontainers send events to their parent containers. The problem with
this approach is subcontainers are not really subcontainers but are related
containers (graph structure rather than tree structure), which can result in
cycle when trying to propagate events from container to container. I
think the solution may be easier than I thought. The ProjectContainerManager has a list of active (open)
containers. It also can locate and open containers that are not
opened. In other words, the ProjectContainerManager knows what included
in the unique set of containers. So, if we have a subcontainer
(related-container) request the ProjectContainerManager send an event to the
containers we can guarantee that the container will only get the message
once. The simplest thing to do would be to have the
ProjectContainerManager to send the event once to each container. We
could try to get more clever by only sending the event containers that are
related-containers of the container that originated the event. The
ProjectManagerContainer would have to look at each container and its
related-containers and create unique list containers to send the event.
It would mean the ProjectContainerManager would have to do cycle detection to
create this unique set. Personally, I don’t think it is worth the
trouble, I think you can send the Collaboration Event to all of the
Containers and let them decide whether it is an event they are interested in
processing. The container could decide that it is interested only in
CollaborationEvents from related-containers and check its list of
related-containers or it could just ignore the Collaboration Event. One remaining question is if a container is closed and it is
going to be sent a Collaboration Event should it be opened so it can process
the event? The originally thinking on the Container is that we would keep
a reference count and if no clients had a container open it would be saved to
disk and closed to conserve memory. Any thoughts? |