SweetHMAC 介绍
SweetHMAC 是个极小，简单易用的 Swift 类，使用 HMAC 算法加密字符串。
字符串扩展：
// Will output this string: e470f785afb708cd8c2a31860642fd11 "I'm going to make him an offer he can't refuse".HMAC(.MD5, secret:"Vito Corleone")
HMAC：
let quote = "I'm going to make him an offer he can't refuse" let author = "Vito Corleone" // Create a SweetHMAC instance with your message and secret strings let hmacEncrypt:SweetHMAC = SweetHMAC(source: quote, secret: author) // Pick some computed HMAC output based on some algorithm using "HMAC" method... let md5 = hmacEncrypt.HMAC(.MD5) // ...or do it more "Sweet" like this let md5 = SweetHMAC(source: quote, secret: author).HMAC(.MD5)