perfsonar development work

[Daniel <>]

Hello,

I'm a developer working on a RNP project which deals with Stream Processing Engines, in a similar way that ps-flowsub deals with flows.

In this project, a client can subscribe to a flow (given a specific query on the stream) sending a QueryRegisterRequest to the WebService, receiving a QueryRegisterResponse saying it was sucessfull registered.

This QueryRegister carries query info, that will be applied into a stream (not webservice's function) being generated in real-time by other applications.

My question is: When the webservice receives a QueryRegisterRequest, is there any "correct" way to make the webservice start sending periodic messages (like, QueryResult) to the client?

I'm asking this because the approach used @ ps-flowsub is to create a zebedee tunnel when a Subscription arrives, the webservice then makes a pseudo-direct connection to the client. I would like to know if it's possible to send periodic nmwg messages without making a direct connection.

Also, I don't see any way to send messages w/o "returning" function to the requestHandler.  I know that perfsonar's message schema is request-response, but is it 1-to-1, or can I send multiple responses to a single request? 

Thanks in Advance, and sorry for the long message.