Supporting different delivery modes for connections about msgflo

[jonnor]

A major problem with option 2) is that is requires changes to the Participant code, making it impossible to use existing/foreign participants. This would limit use to systems where one has complete control over each node. And make nodes participate in multiple networks/system very difficult.
So the way forward seems to be the bindings approach.
Note that we might want to have minimal support for participants self-initializing with possibly matching queues, but this will then be secondary. Major reason for this right now is allowing use on Heroku/AMQP without needing Coordinator to set up communication...

For MQTT and similar systems where the Broker cannot provide this functionality, a helper will be used by the Coordinator to perform this role. Probably hidden behind the transport.MessageBroker interface.

[jonnor]

Another problem is consoliating the need for various type of communication stategies. For instance in http://github.com/jonnor/imgflo-server we want round-robin between API frontend and the workers, but the result from worker should be communicated back to the API frontend which made the processing request.
The back-comm can be done using either a reply-to/peer-based model, or pub-sub.

Current thinking is to make edges be pub-sub by default (currently its transport dependent), and let a special router component implement round-robin. In AMQP (and other transports with neccesary capabilities) this would not actually be code in the coordinator, but instead just configure the broker suitably. On MQTT etc it will be implemented using a helper in the coordinator.
ACK/NACK would the be optional??

[jonnor]

All transports are now pub-sub by default. Need to still develop a msgflo/RoundRobin type component/participant

[jonnor]

RoundRobin now exists since 1+week

[jonnor]

Inside one role on AMQP, round-robin is the default since 2016. One can use msgflo/PubSub pseudo-component in order for all participant of a single-role to all get the message. Example usage in imgflo-server