Missing parameters with RESTful request when upgrading to Grails 2.3.0 - rest

Question

I am using Grails with RESTful to develop my web application. Everything works fine, till I upgrade my application to Grails 2.3. Here is my UrlMappings:
I still send request, submit or do some other things normally, but in POST, PUT requests, the parameters are missing. Server just recognize only the parameters I put on the URL directly, but the remain I enclose in form or model when submit cannot be found in the "params" variable. He is my UrlMappings:
class UrlMappings {
static mappings = {
"/$controller/$action?/$id?"{ constraints {} }
name apiSingle: "/api/$controller/$id"(parseRequest:true){
action = [GET: "show", PUT: "update", DELETE: "delete"]
constraints { id(matches:/\d+/) }
}
name apiCollection: "/api/$controller"(parseRequest:true){
action = [GET: "list", POST: "save"]
}
name api2: "/api/$controller/$action"(parseRequest:true)
name api3: "/api/$controller/$action/$id"(parseRequest:true)
"/"(view:"/welcome")
"500"(view:'/error')
}
}
I have read the latest document of Grails 2.3, at http://grails.org/doc/latest/guide/theWebLayer.html#restfulMappings
but I think it is not clear. I have tried it follow the documentation but have no result. And there are no any sample about using Grails 2.3 with RESTful for me to refer.
How can I make it work normally as before, and can access all parameter values in REST request? Thank you so much!

Answer 1

According to this http://grails.1312388.n4.nabble.com/Grails-2-3-and-parsing-json-td4649119.html parseRequest has no effect since Grails 2.3
If you use JSON as request body you can accees request params as request.JSON.paramName
As a workaround you can add a filter that will populate data from JSON to params:
class ParseRequestFilters {
def filters = {
remoteCalls(uri: "/remote/**") {
before = {
if (request.JSON) {
log.debug("Populating parsed json to params")
params << request.JSON
}
}
}
}
}

Answer 2

Adding on to Kipriz's answer and cdeszaq's comment, you can write a recursive method to inject nested params. Something along these lines:
public void processNestedKeys(Map requestMap, String key) {
if (getParameterValue(requestMap, key) instanceof JSONObject) {
String nestedPrefix = key + ".";
Map nestedMap = getParameterValue(requestMap, key)
for (Map.Entry<String, Object> entry : nestedMap.entrySet()) {
String newKey = nestedPrefix + entry.key;
requestMap.put(newKey, getParameterValue(nestedMap, entry.key))
processNestedKeys(requestMap, "${nestedPrefix + entry.key}");
}
}
}
public static Map populateParamsFromRequestJSON(def json) {
Map requestParameters = json as ConcurrentHashMap
for (Map.Entry<String, Object> entry : requestParameters.entrySet()) {
processNestedKeys(requestParameters, entry.key)
}
return requestParameters
}