upload to s3 with accelerated endpoint swift

uploads3.swift

// initiation in appdelegate
let east1Configuration = AWSServiceConfiguration(
            region: AWSRegionType.USEast1,
            credentialsProvider: credentialsProvider
            )!
let largeImageConfiguration = AWSS3TransferUtilityConfiguration()
        largeImageConfiguration.isAccelerateModeEnabled = true

AWSS3TransferUtility.register(with: east1Configuration, 
                              transferUtilityConfiguration: inputImageConfiguration, 
                              forKey: S3ConfigurationKey.smallImage.rawValue)



// function definition
static func uploadData(data:Data, uploadPath:String, bucket:String, endpoint:S3ConfigurationKey){
        
        let expression = AWSS3TransferUtilityUploadExpression()
        expression.progressBlock = {(task, progress) in
            debugPrint(task, progress)
        }
        
        var completionHandler: AWSS3TransferUtilityUploadCompletionHandlerBlock?
        completionHandler = {(task, error) -> Void in
            guard error == nil else {debugPrint(error!); return}
            debugPrint("task upload completed")
        }
        
        
        
        
        let transferUtility = AWSS3TransferUtility.s3TransferUtility(forKey: endpoint.rawValue)!
        
        
        transferUtility.uploadData(data,bucket: bucket, key: uploadPath, contentType: "text/plain", expression: expression, completionHandler: completionHandler).continueWith {
            (task) -> AnyObject? in
            guard task.error == nil else {debugPrint(task.error!); return nil}
            if let result = task.result {
                debugPrint(result)
            }
            return nil
        }
    }