Any use case for SOAP over SMTP/JMS?

Question

I've frequently used SOAP over HTTP for web services that so far worked great and with REST this is only choice we're left with.

I would like to know If you've come across a use case/scenario in your projects that needs SOAP over SMTP or SOAP over JMS type of communication? I'm just trying to understand uses of SMTP or JMS with SOAP?

Answer 1

Both SMTP, and most JMS implementations, provide queueing of messages. If you need to reliably send a message to an endpoint that may not be available, they are both reasonable choices.

JMS implementations often add additional properties, such as in-order delivery, the ability to select the appropriate level of assurance (eg: at least once, only once, etc), the ability to load-balance processing more easily, and various topologies such as broadcast or fan-out.

These are really properties of the underlying transport, and would be equally valid if you replaced SOAP with "custom JSON", XML, or any other message encoding in your question.