let userName = "myUsername"
let password = "myPassword"
let authString = userName + ":" + password
let credentialData = authString.dataUsingEncoding(NSUTF8StringEncoding)!
let base64Credentials = credentialData.base64EncodedStringWithOptions([])

let headers = ["Authorization": "Basic " + base64Credentials]
let url = URL(string: api)!
Alamofire.request(url, method: .post,
                parameters: params,
                encoding: JSONEncoding.default,
                headers: headers)
    .validate().responseJSON { (response) in
    print(response)
}