JEP-0060: Publish-Subscribe suitable forHTTP/POX XML Based EDA / Pub Sub?

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Hi, I’'m relatively new to XMPP so give me some slack if this a lame question …

I use pub/sub - event driven architecture heavily for integration. We use JMS for the pub/sub.

The WS-* world has some specs out there that are trying to make this platform independant. I have convinced myself that WS-* is going to fail so I don’'t want to go near them.

I glanced at JEP-0060: Publish-Subscribe over the weekend and am wondering if it could be an alternative? The one thing I didn’'t see in it was the concept of durable subscriptions.

For a bit more background on what I am talking about, here is a post on my blog discussing it:

HTTP/POX XML Based EDA / Pub Sub ?

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Hey Mike,

In JEP-60: Pubslish-Subscribe subscriptions are always persistent. That means that if the server/service goes down when it is restarted again subscriptions will be there. PubSub also specifies a concept called “leasing” where subscriptions can expire in a certain date. Anyway, subscriptions should be explicitly deleted by the subscriber or any node owner. And the expiration date (if any and if supported by the pubsub service) can also be configured by the subscriber.

PubSub in XMPP is meant to be used by XMPP clients (i.e. XMPP entities). That means that XMPP clients should also support PubSub (JEP-60) to be able to use the pubsub service hosted by the server. It is also possible to add “adapters” to the pubsub service where the adapter could let you integrate pubsub with any other type of application (e.g. email system, nntp, HTTP, etc.). Therefore, if you are looking for a solution that will let you just publish an item to a node by submitting an HTTP request using Plain Old XML (POX) you may use pubsub and you will also need to write an HTTP adapter. The HTTP/POX adapter would be a servlet that is added to the servlet container (e.g. jetty, tomcat, websphere, etc.) that parses the POX and interacts with the pubsub service. The HTTP adapter can also let users subscribe to nodes or whatever you need.

BTW, pubsub support will be released in Wildfire 2.6.0 that is coming out April 6th.

Regards,

– Gato

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Hello!

> BTW, pubsub support will be released in Wildfire

> 2.6.0 that is coming out April 6th.

Great news!

After taking a look into JEP-060 it looks like this openes up a whole new universe. So, could you pls elobarate a little bit, what/how much/etc. we will be able to do with V2.6, maybe some examples.

Bye

Starry

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Hi Gato,

Thanks for the response.

I read the spec in more detail last night. Impressive spec. Think that it will be very useful in many ways.

I’‘m not sure if it fits with what I am envisioning though. I’'m thinking of a HTTP / REST based pub/sub. Basically 100% platform indepdent pub/sub. I posted an initial reaction to JEP-0060 here:

Initial Thoughts on JEP-0060 Pub/Sub

Let me know if you think I’‘m off on my thinking … as I said, I’'m new to XMPP.

Thanks again for the response.

Mike