The URL that you use to access a custom apex rest service is determined by the @RestResource annotation, which can only be used at the class level.
So it makes sense for Salesforce to only allow a single @HttpPost method in a @RestResource annotated class. There would be no way to provide a more specific URL to be able to choose between two @HttpPost methods. The @HttpPost method also needs to be static, so that precludes using inner classes to help juggle things.
What you can do, however, is have your @HttpPost method act as a receptionist. Your @HttpPost method stands at the front door and interacts with all incoming requests. You can then have several other methods (or other classes) that your @HttpPost receptionist dispatches the incoming request to.
Something like
@RestResource(urlMapping='/my/endpoint/*') global class MyRestAPI{ // You could use an if/else if chain or a switch statement to take care of this, // but I personally find using a Map to be more elegant private static Map<String, iRestPostHandler> resourceToHandler = new Map<String, iRestPostHandler>{ '/my/endpoint/service1' => new Service1Handler(), '/my/endpoint/service2' => new Service2Handler() }; @HttpPost global static void dispatch(){ // @Http<X> annotated methods have access to the RestContext variable, which // contains a RestRequest instance // The RestRequest contains the request URI, which will always start with the // urlMapping defined in the @RestResource annotation if(resourceToHandler.containsKey(RestContext.request.requestURI)){ // dispatch to the appropriate class resourceToHandler.get(RestContext.request.requestURI).handleRequest(RestContext.request, RestContext.response); } } public interface iRestPostHandler{ // Have the interface take both the request (so you can handle the request body // separately in each concrete class) and response (so that the dispatcher // doesn't need to worry about handling output) void handleRequest(RestRequest req, RestResponse resp) } // Because we don't need to use the @HttpPost annotation (not like we could), we // can make use of inner classes public class Service1Handler implements iRestPostHandler{ public void handleRequest(RestRequest req, RestResponse resp){ Map<String, Object> requestBodyDeserialized = JSON.deserializeUntyped(req.requestBody); //do work } } public class Service2Handler implements iRestPostHandler{ public void handleRequest(RestRequest req, RestResponse resp){ Map<String, Object> requestBodyDeserialized = JSON.deserializeUntyped(req.requestBody); //do different work } } }
