Making the Broker Client Direct Dial Aware
Yesterday I worked on the Broker's C++ Service adapter to allow for these direct dial connections with the addition of the boost asio acceptor listening on a ephemeral port and putting that in the registration message to the Broker. That looked to be pretty good, and so today I worked on adding the client-side of the protocol.
I went with a simple scheme - if the user explicitly asks to locate() a service, then we'll ask the Broker for the direct dial location, and save it. Then, for every connection to that service, we'll have a pool of connections to use that connect directly to the service and do not go through the Broker.
There's a hitch - if the Broker is trying to load balance my calls, then I'm going to mess him up as I am creating a pool on the one and only location he's giving me. This isn't great, but the alternative is to not have any pooling of connections and ask the Broker for the location each time, and then create a connection and then throw it away.
It's possible, but I decided against it. I think there's more value in this pooling, but we'll see. Maybe I'm all wet and the real value is in asking the Broker each time. We'll have to see how it plays out in the usage patterns.