sending JSON using simple RKClient post - objective-c

Question

I'm trying to send a request using RestKit. I want it to be sent in JSON, but it seems that default post methot from RKClient uses some kind of FORM data formatting (I check it using [request HTTPBodyString]).
I need to send the data using simple POST, like this (I'm not using object mapping):
[[RKClient sharedClient] post:path usingBlock:^(RKRequest* req) {
req.params = params;
req.delegate = self;
}];
I found some solutions that use NSJSONSerialization, but that method crashes when I put NSDate object in my JSON dictionary.
Is there a way to tell the RKClient to send requests using JSON?
Update: params is a NSDictionary. I want to be able to tell RestKit to serialize my dictionary using JSON when sending it by POST.

Answer 1

You can do this by setting the RestKit's serializationMIMEType property to RKMIMETypeJSON.
E.g.
[RKObjectManager sharedManager].acceptMIMEType = RKMIMETypeJSON;
[RKObjectManager sharedManager].serializationMIMEType = RKMIMETypeJSON;
see also http://restkit.org/api/master/Classes/RKObjectManager.html:
The desired serialization format is configured by setting the
serializationMIMEType property. RestKit currently supports
serialization to RKMIMETypeFormURLEncoded and RKMIMETypeJSON.
Update:
Example for posting a plain JSON String with the correct Mime Type:
RKParams *params = [RKRequestSerialization serializationWithData:[jsonString dataUsingEncoding:NSUTF8StringEncoding]
MIMEType:RKMIMETypeJSON];
[[RKObjectManager sharedManager].client post:#"/mypath"
params:params
delegate:self];
Update 2:
Getting JSON from a NSDictionary object:
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:myNSDictionaryObject
options:NSJSONWritingPrettyPrinted
error:&error];
jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];