Remote message broadcasting about protoactor-go HOT 7 CLOSED

In think we should synchronize this with the other idea of wrapping all messages in an envelope as proposed in #69.

For example, how would we handle message headers for a broadcasted message sent over the wire? Could we build broadcasting into the general message envelope by having a list of recipients? Or would it be better to wrap one of the envelopes inside the other? (and if so, in which order?)

I'm leaning towards either merging the two envelopes, or wrapping the broadcast envelope in the message envelope.

from protoactor-go.

I think the two are separate. I see BroadcastEnvelope as an implementation detail for optimizing the delivery of a message to multiple PIDs that exist on one or more remote nodes. We would generate an envelope for each remote node, with the subset of PIDs residing on that node.

As I understand it, a Message is sent via Tell, Request, etc, to a single PID. There could be middleware that inspects a header with a list of PIDs to forward this message, but I don't see that as the same thing. Something worth noting is if the header used a PIDSet to broadcast the message, it should benefit from the same optimizations based on the proposed PIDSet.Tell API.

from protoactor-go.

As I see this, there are two ways this could be implemented:

1. Which I guess is what @cpx86 is leaning towards.

We have a LocalEnvelope, a RemoteEnvelope and a BroadcastEnvelop. all of which carry the message header information to the receiver.

Or

2. We separate them to be only LocalEnvelope and RemoteEnvelope, and make the BroadcastEnvelope a separate thing with no headers.

This would mean that if we broadcast to a remote node, the broadcast envelope would have to contain a RemoteEnvelope internally. in order to also carry the header information.

from protoactor-go.

One thing we could do, is to let the current MessageEnvelope (in Remote) take a list of ID's instead of a PID target.

So a message could be sent to 1-n actors on a remote nod.

Not sure how this would affect allocations in the default (1 target) case.
But in theory, there is not really any different between having 1 or more targets

from protoactor-go.

Q: What is the difference between a LocalEnvelope and a RemoteEnvelope?

MessageEnvelop could work – as it also represents a single message to be delivered. It could be optimized to take one or more Ids instead of a single PID, which I doubt would add noticeable overhead.

from protoactor-go.

A LocalEnvelope could carry a Message interface{}, a remote envelope must serialize.

from protoactor-go.

Not planned for now

from protoactor-go.