On 07/01/2020 5:01 am, tomt wrote:
As far as the naming of topics in the broker, I had asked last time about dot notation vs slashes since I had read the AMQP 1.0 addressing spec. Does it make sense to use slashes in the naming for topics to be inline with the addressing spec?
It doesn't make any difference to qpid-cpp (or the router).
As far as my expected setup goes, I have 4 machines dedicated to my exploration effort here and I am running the qpid-cpp broker in HA mode. I also have a router on each machine that points to the active broker. In the event of a broker failover to another node, the router configurations are expected to be modified on the fly to point to the newly active broker. My routers have link routing configured so any topic with a given prefix can be subscribed to from any machine in my cluster by any number of clients unknown to me. I would think the clients would have no idea that anything changed under the covers but have not yet had a chance to test this. It looks like this dispatcher config using link routers should work for my needs over broker messaging unless I'm missing something. From what I can tell, in broker messaging you must define the ins and outs for each queue in qdrouter's configuration where link routing is more flexible by creating the virtual tunnel you mentioned for the link. I can even set link options like timeout, which is important next.
Agreed, link routing is what you want for an arbitrary number of independent topic subscriptions.
I have seen in the broker that the defined name for the virtual tunnel is <router_id>:<container_id>@<subscription_name> (or something very close to that). If my AMQP client that is connected to one router unexpectedly moves over to another router, can it attach to the existing link on the new router (if the router names are all the same)?
I don't think the router names *can* be the same, as they need to be uniquely identified. For durable (or reliable) subscriptions, that will indeed likely pose a problem, not from where the client is attached but from which router is connected to the broker (as it is the container id of that router that the broker will see).
You can set a 'shared' capability on the link source, in which case the c++ broker will use only the link name (not qualified by the container id).
--------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
