RestKit send post request, parse the result? - iphone

Question

I'm trying to pull data from my web service API and parse the received JSON... I've been though RestKit tutorials, but I couldn't find any information on doing a post request!
Right now I have this code:
-(void) loadPerformers
{
// Create our request mapping
RKObjectMapping* requestMapping = [RKObjectMapping mappingForClass:[JsonOperationModel class]];
[requestMapping addAttributeMappingsFromArray:#[#"RequestType"]];
// Create our data mapping
RKObjectMapping* dataMapping = [RKObjectMapping mappingForClass:[DataModel class] ];
[dataMapping addAttributeMappingsFromArray:#[#"Status"]];
// Create our performer mapping
RKObjectMapping* performerMapping = [RKObjectMapping mappingForClass:[PerformerModel class] ];
[performerMapping addAttributeMappingsFromArray:#[#"IdPerformer", #"Name", #"Rate",
#"IsInWatch", #"Rating", #"PictureUrl", #"LastModifiedDate"]];
// Create our talent mapping
RKObjectMapping* talentMapping = [RKObjectMapping mappingForClass:[DataModel class] ];
[talentMapping addAttributeMappingsFromArray:#[#"Id", #"Value"]];
// Define the relationship mapping with request -> data
[requestMapping addPropertyMapping:[RKRelationshipMapping relationshipMappingFromKeyPath:#"data"
toKeyPath:#"data"
withMapping:dataMapping]];
// Define the relationship mapping with data -> performers
[requestMapping addPropertyMapping:[RKRelationshipMapping relationshipMappingFromKeyPath:#"Performers"
toKeyPath:#"Performers"
withMapping:performerMapping]];
// Define the relationship mapping with performer -> talent
[requestMapping addPropertyMapping:[RKRelationshipMapping relationshipMappingFromKeyPath:#"Talents"
toKeyPath:#"Talents"
withMapping:talentMapping]];
RKResponseDescriptor *responseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:JsonOperationMapping pathPattern:nil keyPath:nil statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];
NSURL *URL = [NSURL URLWithString:#"http://10.10.5.106:8089/Mobile/Default.ashx"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];
RKObjectRequestOperation *objectRequestOperation = [[RKObjectRequestOperation alloc] initWithRequest:request responseDescriptors:#[ responseDescriptor]];
[objectRequestOperation setCompletionBlockWithSuccess:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) {
RKLogInfo(#"result: %#", mappingResult.array);
} failure:^(RKObjectRequestOperation *operation, NSError *error) {
RKLogError(#"Operation failed with error: %#", error);
}];
[objectRequestOperation start];
}
Which was a sample on an official tutorial of RestKit, modified to my needs according to my json. But how can I adapt this sample to send a JSON string to the URL, and then fetch the server anwser?
I couldn't find any information on that, and each of my server response needs some client information sent through a JSON string before being able to send a response back to the client. (It's isn't only fetching from an URL as my current sample does!)
Thanks for any input on this!