Upload images to Qiniu via multipart-form with Alamofire

QNUploader.swift

//
//  QNUploader.swift
//
//  Created by Lex on 12/1/15.
//

import Foundation
import Alamofire

private let kCDNDomain = "__YOUR_QINIU_CDN_DOMAIN__"
private let kUploadDomain = "http://upload.qiniu.com/"

typealias QNUploadCompletion = ((URL: NSURL?) -> Void)

struct QNUploader {

    func uploadImage(image: UIImage, token: String, completion: QNUploadCompletion?) {
        guard let data = UIImageJPEGRepresentation(image, 0.7) else {
            completion?(URL: nil)
            return
        }

        Alamofire.upload(.POST, kUploadDomain, multipartFormData: {
            form in
            form.appendBodyPart(data: data, name: "file")
            form.appendBodyPart(
                data: token.dataUsingEncoding(NSUTF8StringEncoding)!,
                name: "token")
            }) { result in
                switch result {
                case .Success(let upload, _, _):
                    upload.responseJSON { response in
                        if let key = response.result.value?["key"] as? String {
                            let URLString = "http://\(kCDNDomain)/\(key)"
                            let URL = NSURL(string: URLString)
                            completion?(URL: URL)
                        } else {
                            completion?(URL: nil)
                        }
                    }
                default:
                    completion?(URL: nil)
                }
        }
    }

}