Grails Restful Controller UPDATE-Method does not take updated Data from PUT - rest

Question

I set up a Restful Controller in my Grails 2.3.5 app. When sending an object via PUT to my endpoint the object won't get updated. My println does not show the updated data, but the original. I don't understand why.
Restful controller:
import grails.rest.RestfulController
class PluginSettingController extends RestfulController {
static responseFormats = ['json', 'xml']
PluginSettingController() {
super(PluginSetting)
}
#Override
def update(PluginSetting setting){
println(setting.name)
// This prints out the old name: "Old name"
}
Domain class:
class PluginSetting {
String name
String value
static constraints = {
name(nullable:false, blank:false, unique: true)
value(nullable:false, blank:false)
}
}
curl request:
curl -i -X PUT -d "{'name':'NEW','value':'my value', 'id':1}" http://localhost:8080/app/pluginSettings/1
old object (this is what i get when sending a GET to the URL 'http://localhost:8080/app/pluginSettings/1')
{
"class": "configuration.PluginSetting",
"id": 1,
"name": "Old name",
"value": "my value"
}

Answer 1

This finally worked for me with Grails 2.5.4 - it was suprise that the normal methods did not work when using a second controller.
#Transactional(readOnly=false) // not needed
class EngineController extends RestfulController<PluginSettings> {
static responseFormats = ['json', 'xml']
EngineController() {
super(PluginSettings)
}
}
class UrlMappings {
static mappings = {
"/$controller/$action?/$id?(.$format)?"{
constraints {
// apply constraints here
}
}
"/"(view:"/index")
"500"(view:'/error')
}
}
#Show
curl -i -X GET -H "Accept: application/json" localhost:8080/app/engine/index
curl -i -X GET -H "Accept: application/json" localhost:8080/app/engine/show/1
#Create
curl -i -X POST -H "Content-Type: application/json" -d '{"name":"Along Came A Spider"}' localhost:8080/app/engine/save
#Update
curl -i -X PUT -H "Content-Type: application/json" -d '{"name":"Along Came A Spider"}' localhost:8080/app/engine/update/1
#Delete
curl -i -X DELETE http://localhost:8080/app/engine/delete/1
However when I modified the urlMappings to include
"/api/engines"(resources:"Engine")
I had to use
curl -i -X GET -H "Accept: application/json" localhost:8080/app/api/engines/
curl -i -X GET -H "Accept: application/json" localhost:8080/app/api/engines/1
curl -i -X POST -H "Content-Type: application/json" -d '{"name":"Along Came A Spider"}' localhost:8080/app/api/engines/
curl -i -X PUT -H "Content-Type: application/json" -d '{"name":"Along Came A Spider"}' localhost:8080/app/api/engines/1
curl -i -X DELETE http://localhost:8080/app/api/engines/1