下载大文件时Alamofire ResponseSerializationFailureReason.inputFileReadFailedFailed

Question

我正在使用Alamofire将文件下载到我的iOS应用程序中，它适用于较小的文件（约1GB或更少），但是当我尝试下载更大的文件时，它会失败。它完成整个下载，达到100％，然后抛出错误：

FAILURE: responseSerializationFailed(Alamofire.AFError.ResponseSerializationFailureReason.inputFileReadFailed(file:///...))

为什么大文件失败？

这是我的代码：

let destination: (URL, HTTPURLResponse) -> (URL, DownloadRequest.DownloadOptions) = {
                (temporaryURL, response) in
                if let directoryURL = FileManager().containerURL(forSecurityApplicationGroupIdentifier: applicationGroup), let suggestedFilename = response.suggestedFilename {
                    let filePath = directoryURL.appendingPathComponent("\(suggestedFilename)")
                    return (filePath, [.removePreviousFile, .createIntermediateDirectories])
                }
                return (temporaryURL, [.removePreviousFile, .createIntermediateDirectories])
            }
            if self.reachability.isReachableViaWiFi {

                var request: DownloadRequest

                if let resumeData = resumeData {

                    request = BackendAPIManager.sharedInstance.alamoFireManager.download(resumingWith: resumeData)
                        .downloadProgress { progress in
                            cell?.progressView.isHidden = false
                            cell?.progressView.setProgress(Float(progress.fractionCompleted), animated: true)
                    }
                } else {
                    request = BackendAPIManager.sharedInstance.alamoFireManager.download(fileLocation, to: destination)
                        .downloadProgress { progress in
                            cell?.progressView.isHidden = false
                            cell?.progressView.setProgress(Float(progress.fractionCompleted), animated: true)
                    }
                }

                request.responseData { response in
                    switch response.result {
                        case .success( _):
                            cell?.pctLabel.text = nil
                            cell?.progressView.isHidden = true
                            break;
                        case .failure:
                            print(response)
                            resumeData = response.resumeData
                    }
                }
            }


class BackendAPIManager: NSObject {
static let sharedInstance = BackendAPIManager()

var alamoFireManager : Alamofire.SessionManager!

var backgroundCompletionHandler: (() -> Void)? {
    get {
        return alamoFireManager?.backgroundCompletionHandler
    }
    set {
        alamoFireManager?.backgroundCompletionHandler = newValue
    }
}

fileprivate override init()
{
    let configuration = URLSessionConfiguration.background(withIdentifier: "com.nw.fileDownload.background")
    configuration.timeoutIntervalForRequest = 14400 // 4 hours
    configuration.timeoutIntervalForResource = 14400
    self.alamoFireManager = Alamofire.SessionManager(configuration: configuration)
}
}