Amazon Product Advertising API Signature in iOS

Question

I am trying to access Amazon's Product Advertising API in my iOS application. Creating the signature seems to be the tough part. On this page:

http://docs.amazonwebservices.com/AWSECommerceService/latest/DG/rest-signature.html

It says to "Calculate an RFC 2104-compliant HMAC with the SHA256 hash algorithm". Amazon also provides a java class to do this for you:

http://docs.amazonwebservices.com/AWSECommerceService/latest/DG/AuthJavaSampleSig2.html

Does anybody know how I can do this in Objective-C instead? I looked into the AWS iOS SDK, but it doesn't seem to include the Product Advertising API.

Answer 1

Actually the AWS iOS SDK DID have a static method to handle all auth situations. Maybe you should take a glance at the AmazonAuthUtils.h :

+(NSString *)HMACSign:(NSData *)data withKey:(NSString *)key usingAlgorithm:(CCHmacAlgorithm)algorithm;
+(NSData *)sha256HMac:(NSData *)data withKey:(NSString *)key;

you can find it in the document: http://docs.amazonwebservices.com/AWSiOSSDK/latest/Classes/AmazonAuthUtils.html