In BSParseDotComRequestSerializer override requestBySerializingRequest:withParameters:error:

Reference
https://github.com/programmingthomas/AFN2-Play-ground/blob/master/AFN2%20Play%20Ground/AFN2%20Play%20Ground/YahooFinanceRequestSerializer.m
In BSHTTPSessionManager add designated initializer, override super’s designated initializer, and revise sharedInstance to set self.requestSerializer