Can an ESB send HTTP POSTs to subscribers?

I'm researching ESBs & Queuing impleme开发者_运维百科ntations and it looks like in most cases when implemented as a pub/sub the subscriber needs to know about the publisher and either needs to initiate a connection to the publisher or watch the topic queue to grab a message.

Do any of the popular solutions support automatically sending messages to an HTTP/S endpoint? I would like to configure topics to send messages to one or many subscribing URLs so when the message hits the queue it automatically fires off a HTTP/S POST.

you can use WSO2 Message Broker[1] for this. WSO2 MB supports WS-Eventing specification which allows users to subscribe using an http end point as an event sink [2]. WSO2 ESB can also comes with this components.

[1] http://wso2.org/library/message-broker

[2] http://wso2.org/library/articles/2011/08/messaging-eventing-soa

wso2 esb supports Queuing implementations and also pub/sub model http://wso2.org/library/esb

Thanks for the feedback. WS-Eventing sent me down another path where I discovered the term I was looking for "Webhooks." A webhook is precisely what I was requesting that I need to implement. However, I didn't necessarily get an answer to my question because I was looking for a reliable & durable service that would handle this for me. However, now I can ask a more specific question about that.

You should checkout PServiceBus(pservicebus.codeplex.com), it support subscribing using a http transport. So when a message is publish to the bus, it will send an HTTP POST to the url that is specified in your subscriber's subscription and it also allows you to customize how the parameter are passed on the url. And example can be found here: http://pservicebus.codeplex.com/SourceControl/changeset/view/e6362c76f12b#pServiceBus%201.0.2%2fSamples%2fInvokeWebService%2fInvokeWebService%2fProgram.cs

In the example, it shows how the ESB can invoke both an HTTP POST and Web Service(I know that is not what you are looking for) using the HttpTransport.

you may look at the following article which explain pub sub with WSO2 ESB, WSO2 MB and WSO2 AS. http://wso2.org/library/articles/2011/12/wso2-esb-example-pubsub-soa

Yes, not only that ESB would support multiple protocols like AMQP, STOMP, SMTP, REST, JMS etc.

Service mix supported it long back using WS-Notification, you can find detail description about the implementation in JBOSS A-MQ, Further it is also possible to implement using JBOSS Fuse Service Works

Disclaimer I have provide the implementation of Fuse Service Works.