incubator-cloudstack-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Murali Reddy <>
Subject Re: Event Publish and Subscribe ( was perhaps Re: Cloudstack Questions )
Date Fri, 18 May 2012 13:12:39 GMT

Are there any use-cases for which it make sense to have publishers (that
use CloudStack API to publish) other than CloudStack? If its not overkill
we can have generic mechanism of publish/subscribe as service in
CloudStack. I can think of tenants workload VM's be able to leverage this
and publish something to subscribers.

On 18/05/12 5:54 PM, "George Reese" <> wrote:

>Here's the way event pub sub should workĊ 
>People interested in events will subscribe to them via API and CloudStack
>will maintain a record that includes:
>* What type of event(s) the subscriber cares about
>* The URI of an endpoint to notify on events
>* An optional API key for signing event publications
>If you want it to be really rich, you allow for multiple notifications
>endpoints, including SMS and email.
>When the existing event management system in CloudStack identifies a
>state change, it published it to a message queue.
>A new CloudStack component is subscribed to the message queue and pulls
>the state change off. It then sends the event to all interested parties.
>It does not keep delivery state. It sends and forgets. The only thing
>resembling state is the counting of failures, eventually killing an
>endpoint that fails to often.

View raw message