IS 8.2 now handles GET, POST, PUT & DELETE http methods. Reverse invoke nodes only serve to proxy requests to your internal IS nodes, the benefit is typically through a firewall. Unless you have specific code or security in your RI nodes, which isn’t typical, the /rest directive will typically be proxied too.
Your rest service 404, from the looks of your post:
is only a matter of changing (.'s & :'s) to /'s.
This is because a rest service translates flow namespace into uri differently to how the /invoke directive does.
PUT to domainName:5555/rest/wmUsers/forums/webServices
A rest service will handle your situation nicely, whilst giving you “out-of-the-box” control of inputs ($resourceID & $path) and also any queryString values.
Continuing with the above example:
PUT to domainName:5555/rest/wmUsers/forums/webServices…
|$resourceID| $path --------------------->
With a rest service, you can do whatever you need with the services $resourceID and/or $path input from here.
Alternatively any queryString values can be captured in the rest service’s input by creating input’s with the associative queryString keys.
PUT to domainName:5555/rest/wmUsers/forums/webServices/
Though usage of queryStrings needs to be evaluated against how specific, by definition, you’re going to be with Resource Oriented Architecture.
I’m initially running blanks about extracting postData into flowServices, but happy to post again if this is how your client is sending data, which I’m guessing is the case being s/mime. Until then, hope this is helpful.