On 18 October 2016 at 22:13, Justin Ross <justin.r...@gmail.com> wrote: > https://gist.github.com/ssorj/1ccf4d1499563722bc419f1e1fac11bf > > In this example, there is still ample credit on the link after the last > on_sendable() is printed, but on_sendable is never fired again. Is that > expected behavior? > > It appears that on_link_flow is only fired when link credit is updated, and > on_link_flow is the source of all on_sendable events. > > https://github.com/apache/qpid-proton/blob/master/proton-c/bindings/python/proton/handlers.py#L36
Thats my understanding from past discussion on these bits. Flow events are raised when a flow frame arrives from the peer, and also generated when sends occur on sending links, I believe to represent that 'credit has changed' (I added a flag in proton-j to allow disabling that, since it makes no sense in many cases). The on_sendable callback then fires when a flow event is handled and there is actually credit to send messages. If the last sendable callback is triggered and you dont have anything to send, then you wont get any more sendable callbacks until more credit arrives from the peer, which if you arent doing anything such as sending it messages, its likely it will never give. Essentially at that point you have been told there is credit to send messages, and its up to you to react and manage doing something to send them [on the container thread] once you do have something to send. --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@qpid.apache.org For additional commands, e-mail: users-h...@qpid.apache.org
