Converting string in Base64 and HMAC sha1

Question

I need help with making a signature in swift 3 with HMAC SHA1 for a web request. I have an example in Java but really do not know how to do it in swift.

Java formula:

signature = Base64.encode(HMAC_SHA1.digest(data,Base64.decode(client_secret))

signature = +t2GOKtZt1hU+C7OGBKZbDOKxds=

Answer 1

Problem solved

extension String {
    func hmac(algorithm: kCCHmacAlgSHA1, key: NSData) -> String {
        let cKey = key
        let cData = self.cString(using: String.Encoding.ascii)
        var cHMAC = [CC_SHA1_DIGEST_LENGTH]
        CCHmac(CCHmacAlgorithm(kCCHmacAlgSHA1), cKey.bytes, cKey.length, cData, Int(strlen(cData!)), &cHMAC)
        let hmacData:NSData = NSData(bytes: cHMAC, length: cHMAC)
        let hmacBase64 = hmacData.base64EncodedString(options: NSData.Base64EncodingOptions(rawValue: 0))
        return String(hmacBase64)
    }
}

let hmacResult: String = cData.hmac(algorithm: HMACAlgorithm.SHA1, key: keyData)