Grails 3.0.1 Respond method Ambiguous method overloading

[jameskleeh]

In 2.4.4 I could call the respond method in my controller and pass into it a map (Ex: respond([name: "Joe"]). Now I get the following exception

Ambiguous method overloading for method grails.artefact.controller.RestResponder$Trait$Helper#respond. Cannot resolve which method to invoke for [class websockets.TestController, class java.util.LinkedHashMap, class java.util.LinkedHashMap] due to overlapping prototypes between: [interface grails.artefact.controller.RestResponder, class java.lang.Object, interface java.util.Map] [interface grails.artefact.controller.RestResponder, interface java.util.Map, class java.lang.Object]

[jeffscottbrown]

I kind of see what is going wrong. We have the same problem with 2.4.4 but it manifests kind of the other way around. In 2.4.4 if you invoke something like respond([name: 'Joe'], [status: 200]) I think the ambiguous method problem will show up. Will get it sorted out. Thanks for the feedback.

[jeffscottbrown]

The tests at https://github.com/grails/grails-core/blob/66c8c7b097b136eb131421e400aef0a8622b4aff/grails-test-suite-web/src/test/groovy/grails/rest/web/RespondMethodSpec.groovy#L234 and https://github.com/grails/grails-core/blob/66c8c7b097b136eb131421e400aef0a8622b4aff/grails-test-suite-web/src/test/groovy/grails/rest/web/RespondMethodSpec.groovy#L244 are now passing.

[jameskleeh]

Thanks @jeffbrown !

[davidtinker]

You can work around this by wrapping your Map and registering a marshaller for your wrapper:

class MapWrapper { Map map }

JSON.registerObjectMarshaller(MapWrapper, { MapWrapper it -> it.map })

respond new MapWrapper(map: [foo: "bar"])

[orubel]

Well problem here... we shouldn't have to wrap a JSON marchaller in every response in every method in every controller.

As this is just passing the resource to the MQ / handlerInterceptor, they are final handoff prior to sending to client and may want to handle formatting prior to return to client. This also simplifies as it is one single point for format handling rather than placing a service call in every controller/method.

[orubel]

There are still errors with this it appears; it seems to always assume a domain as a resource. A resource can be a linkedhashmap, a commandobject, an algorithm, a list, an enum, etc. The method needs to allow for a generic Object or Model to be passed or for for passed Object to be easily converted to the generic type.

As of right now, this is still broken as render does not work with 'after' in handlerInterceptor' and this ('response') does not work with anything besides domain resource it appears.

[orubel]

Hmmm... Ok still a problem but you can get around by just returning result ...which I guess I should be doing anyway for what I am talking about. But this should be able to handle various data it seems.

[jeffscottbrown]

@orubel

Hmmm... Ok still a problem

In which version is it still a problem, and what is the problem?

[orubel]

3.0.4. I don't think this is an issue though as I see my problem. 'return' can handle response fine without sending view. Problem exists with handlerInterceptor and how 'after' method will ALWAYS expect VIEW if response is sent ... even if returning false (see #9175)

Opened ticket #9175 for this