AWS S3 iOS SDK: How to resume upload after connection is interrupted? - ios

Question

This is my code to accomplish the upload task:
let image = UIImage(named: "12.jpeg")
let fileManager = FileManager.default
let imageData = UIImageJPEGRepresentation(image!, 0.99)
let path = (NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] as NSString).appendingPathComponent("\(imageData!).jpeg")
fileManager.createFile(atPath: path as String, contents: imageData, attributes: nil)
let fileUrl = NSURL(fileURLWithPath: path)
uploadRequest?.bucket = "testrawdata"
uploadRequest?.key = "test/loodfd.jpeg"
uploadRequest?.contentType = "image/jpeg"
uploadRequest?.body = fileUrl as URL!
uploadRequest?.serverSideEncryption = AWSS3ServerSideEncryption.awsKms
uploadRequest?.uploadProgress = { (bytesSent, totalBytesSent, totalBytesExpectedToSend) -> Void in
DispatchQueue.main.async(execute: {
print("bytes sent \(bytesSent), total bytes sent \(totalBytesSent), of total \(totalBytesExpectedToSend)")
})
}
transferManager?.upload(uploadRequest).continue(with: AWSExecutor.mainThread(), withSuccessBlock: { (taskk: AWSTask) -> Any? in
if taskk.error != nil {
// Error.
} else {
// Do something with your result.
}
return nil
})
}
I know I don't need to apply it to image, but this is just an example, by default I'm going to send files like 100mb.
When I put my phone into airplane mode during the transfer then turn the network on again, it does not finish the upload task.
Docs are not saying explicitly what should I do to resume interrupted task.
Here is what I tried:
I put initialization of request and manager into viewDidLoad() to assure I'm not creating another request
class ViewController: UIViewController {
var uploadRequest:AWSS3TransferManagerUploadRequest!
var transferManager: AWSS3TransferManager!
override func viewDidLoad() {
super.viewDidLoad()
uploadRequest = AWSS3TransferManagerUploadRequest()
transferManager = AWSS3TransferManager.default()
}
and tried to call
func resumeTransfer() {
transferManager?.resumeAll(nil)
}
But it does not work.
Thanks in advance

Answer 1

It turns out that Transfer Utility is the right tool to accomplish this task
func uploadData(data: NSData) {
let expression = AWSS3TransferUtilityUploadExpression()
expression.progressBlock = progressBlock
let transferUtility = AWSS3TransferUtility.default()
transferUtility.uploadData(
data as Data,
bucket: "test",
key: "test/test.jpeg",
contentType: "image/jpeg",
expression: expression,
completionHander: completionHandler).continue(successBlock: { (task) -> AnyObject! in
if let error = task.error {
NSLog("Error: %#",error.localizedDescription);
}
if let exception = task.exception {
NSLog("Exception: %#",exception.description);
}
if let _ = task.result {
NSLog("Upload Starting!")
// Do something with uploadTask.
}
return nil;
})
}
This way all upload stuff happens in the background, I don't have to worry about app being killed by the iOS, about networks problem etc.
One can even specify
configuration?.allowsCellularAccess = false
in AWSServiceConfiguration
to resume the task only when wifi is available.