How to download a file from a AWS S3 bucket in iOS? - ios

Question

In my iOS app, I try to download a file from an AWS S3 bucket. Here is what I tried:
I initialize AWSMobileClient:
import AWSMobileClient
import AWSS3
let configuration = AWSServiceConfiguration(
region: AWSRegionType.EUCentral1,
credentialsProvider: AWSMobileClient.default())
AWSServiceManager.default().defaultServiceConfiguration = configuration
AWSMobileClient.default().initialize { (userState: UserState?, error: Error?) in
if (userState != nil)
{
print("Initialize OK : \(userState.debugDescription)")
}
if (error != nil)
{
print("Initialize error: \(String(describing: error))")
}
}
I got:
"initialize OK : Optional(AWSMobileClient.UserState.guest)"
Now I try to download a file:
let expression = AWSS3TransferUtilityDownloadExpression()
expression.progressBlock = {(task, progress) in DispatchQueue.main.async(execute: {
print("Progress : \(progress)")
})
}
let completionHandler: AWSS3TransferUtilityDownloadCompletionHandlerBlock = {
(task: AWSS3TransferUtilityDownloadTask, url: URL?, data: Data?, error: Error?) -> Void in
DispatchQueue.main.async(execute: {
print("End download 1")
})
}
let fileManager = FileManager.default
let fileURL = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent("100.ogg")
let transferUtility: AWSS3TransferUtility = AWSS3TransferUtility.default()
transferUtility.download(
to: fileURL,
bucket: "my-s3-bucket",
key: "100.ogg",
expression: expression,
completionHandler: completionHandler).continueWith { (task) -> AnyObject? in
if let error = task.error {
print("Error download : \(error)")
}
if let result = task.result {
print("Result : \(result.debugDescription)")
}
print("End download 2 : \(fileManager.fileExists(atPath: fileURL.absoluteString))")
return nil
}
I got:
"Result : <AWSS3TransferUtilityDownloadTask: 0x6000020bd4d0>
"End download 2 : false"
I don't get any progress, and I also don't get the "End download 1"
So basically, I dont get any error, but it does look like nothing has been downloaded. Also, on a side note, it works well with the Android version of my app, so it's very likely that there is an error in my code.
So what should I change to make it work?
Thanks.

Answer 1

My bad, the example above is actually working, But I had to:
change fileManager.fileExists(atPath: fileURL.absoluteString)) by fileManager.fileExists(atPath: fileURL.path))
check if file exists in the first completionHandler (where I wrote print("End download 1"))