RestKit 0.20 Posting object's attributes on conditional basis - ios

Question

I have complex JSON handling large amount of data, I need to optimise network traffic by sending only required attributes of mapped object to server.
For simplicity lets say I have following User class :
#property (nonatomic, retain) NSString *email;
#property (nonatomic, retain) NSString *fname;
#property (nonatomic, retain) NSString *password;
#property (nonatomic, retain) NSString *profilePic;
#property (nonatomic, retain) NSString *sname;
#property (nonatomic, retain) NSString *status;
#property (nonatomic, retain) NSString *token;
#property (nonatomic, retain) NSString *username;
#property (nonatomic, retain) NSNumber *isLoggedIn;
#property (nonatomic, retain) NSDate *dateCreated;
and my attributes mapping dictionary is following :
[dic addEntriesFromDictionary:#{
#"fname": #"fname",
#"sname": #"sname",
#"profilePic": #"profilePic",
#"email": #"email",
#"username": #"username",
#"password": #"password",
#"status": #"status",
#"token": #"token",
#"isLoggedIn": #"isLoggedIn",
#"dateCreated": #"dateCreated"
}];
For Signin call I needs to post just username & password as following JSON :
{
"user": {
"password": "password",
"username": "demouser"
}
}
While for Signup call I needs to POST entire User object so I cant downsize mapping dictionary. I needs to apply same procedure to lot more complex JSON.
How can I send required attributes of an object in POST call on conditional basis in an optimal fashion?
Thanks.

Answer 1

You are free to create multiple mappings for the same class / entity type - there is no restriction. Each mapping is associated with other mappings / request descriptor / response descriptor and this is where you need to concentrate on identification and uniqueness.
It may be simplest for you to have one request mapping which covers all of the attributes, and whose class is NSDictionary. Then, to use this mapping for a request you use KVC (dictionaryWithValuesForKeys:) to extract only the keys of interest from your true source object into a dictionary that you can then supply to the object manager for mapping and transmission.