使用Alamofire下载文件

Question

I'm downloading a file to a custom file path like this:

let tempFilePath = self.makeTempFilePath()
Alamofire.download(.GET, downloadURL) { temporaryURL, response in
    return tempFilePath
}

How do I know when the download is complete and the success/failure status? I tried responseData closure but result parameter always appears as "failure".

Answer 1

I'm afraid that you can do is use the Downloading a File w/Progress explained in the documentation of Alamofire like the following:

Alamofire.download(.GET, "http://httpbin.org/stream/100", destination: destination)
     .progress { bytesRead, totalBytesRead, totalBytesExpectedToRead in
         print(totalBytesRead)

         // This closure is NOT called on the main queue for performance
         // reasons. To update your ui, dispatch to the main queue.
         dispatch_async(dispatch_get_main_queue) {
             print("Total bytes read on main queue: \(totalBytesRead)")
         }
     }
     .responseData { response in
         print(response)
     }

With the above code you can know the totalBytesExpectedToRead and the totalBytesRead and in part know the difference between both to check if the file was downloaded or not.

In any case you can use too the Accessing Resume Data for Failed Downloads explained in the Alamofire doc in any case of failure during the download process.

I hope this help you.