RESTKit - post a large array of objects to server - ios

Question

How can I post an array of objects to my server with RESTKit?
I have a custom object called Contact which have some properties like name, phone etc. I would like to send an array of these Contact objects to the server.
The method I know for this is postObject:path:parameters:success:failure, but what object I put here? If I put Contact - how will it know it is an array? and if I put NSArray, how will it know it is a Contact?
My Contact object header file is:
#interface Contact : NSObject
#property (strong, nonatomic) NSString *name;
#property (strong, nonatomic) NSString *phone;
#property (nonatomic) NSInteger order;
#property (strong, nonatomic) NSString *firstName;
#property (strong, nonatomic) NSString *lastName;
#end
my response mapping is:
RKObjectMapping *personMapping = [RKObjectMapping mappingForClass:[Contact class]];
[personMapping addAttributeMappingsFromDictionary:#{
#"username": #"name",
#"firstname" : #"firstName",
#"lastname" : #"lastName",
}];
my response descriptor is:
RKResponseDescriptor *personResponseDescriptorForArrayOfPhones =
[RKResponseDescriptor responseDescriptorWithMapping:personMapping
method:RKRequestMethodANY
pathPattern:#"getUsersInfoByPhones"
keyPath:nil
statusCodes:[NSIndexSet indexSetWithIndex:200]];
my request mapping is:
RKObjectMapping *personRequestMapping = [RKObjectMapping requestMapping ];
[personRequestMapping addAttributeMappingsFromDictionary:#{
#"name": #"username",
#"firstName" : #"firstName",
#"lastName" : #"lastName",
#"phone" : #"usernames"
}];
my request descriptor is:
RKRequestDescriptor *personRequestDescriptor = [RKRequestDescriptor requestDescriptorWithMapping:personRequestMapping
objectClass:[Contact class]
rootKeyPath:nil
method:RKRequestMethodAny];
Does this implementation looks good?
Also, this array I want to send to the server could be very big, around 200-1000 objects. Is that possible with RESTKit?
Update: Actually, I would prefer to send an array of strings (which would be phone numbers), and get from the server the Contact objects I have. How can I set RESTKit to post the array of strings and to expect a response of an array of Contact objects?
The json I need to send looks like this:
{
"usernames":["11","22"]
}
the json I expect to get is:
[
{
"_id" : "53e23a54e811310000955f70",
"profileUpdatesCounter" : 3,
"lastname" : "SMITH",
"firstname" : "BOB",
"username" : "11"
}
]