ios - RESTKIT : deserialize JSON with not all relationship attribute -

i tried deserialize json :

{"id":1234, "content": "hi, message", "datesaved":"10/04/2015 11:00", "user":{"id":12}} 

model :

class message: nsmanagedobject {     @nsmanaged var content: string     @nsmanaged var datesaved: nsdate     @nsmanaged var id: nsnumber     @nsmanaged var user: user }  class user: nsmanagedobject {     @nsmanaged var id: nsnumber     @nsmanaged var login: string     @nsmanaged var mobile: string     @nsmanaged var password: string     @nsmanaged var picture: nsdata     @nsmanaged var messages: nsset } 

the user saved in ios data base, don't need send data server. problem both rkrelationshipmapping , rkconnectiondescription seem not done kind of works : first works complete objects, can directly operate coredata ; second 1 can used identifier , not object

i can not change way server serialize objects json, because other android app works kind of json

somebody knows how solve issue?

ok figured out. have forgotten set method addattributemappingsfromdictionary rkrelationshipmapping :

let messageattributesmapping = [     "id":  "id",     "content":  "content",     "datesaved":  "datesaved" ]  extension message {     class func mappingresponse(managedobjectstore: rkmanagedobjectstore) -> rkmapping {         let messagemapping = rkentitymapping(forentityforname: "message", inmanagedobjectstore: managedobjectstore)          messagemapping.identificationattributes = ["id"]         messagemapping.addattributemappingsfromdictionary(messageattributesmapping)          let usermapping = rkentitymapping(forentityforname: "user", inmanagedobjectstore: managedobjectstore)         usermapping.identificationattributes = ["id"]         usermapping.addattributemappingsfromdictionary(["id" : "id"])          messagemapping.addpropertymapping(rkrelationshipmapping(fromkeypath: "user", tokeypath: "user", withmapping: usermapping))          return messagemapping     } } 

this solution works deserialize json, still wondering if should try use rkconnectiondescription, seemed built relationship have id?