iOS Swift：Firebase 存储上传错误 - 只有初始文件上传有效

Question

Environment: Xcode 12.0.1 (Swift 5.x) iOS 13 Firebase 6.34.0 FirebaseFirestore 1.19.0 FirebaseStorage 3.9.1 GoogleDataTransport 7.5.1 PromisesObjC 1.2.11

Problem: I initialize Firebase in iOS app and successfully write database data to Cloud FireStore. I then upload related video file to Firebase Storage with an asynch call.

1. Cloud Firestore database writes ALWAYS work.
2. Using the index generated from Cloud Firestore write, Firebase storage is then used to upload a video and a data file with names as the index from (1) above.

The first first file upload always works with a new app launch. The second or any additional file upload fails with the following error:

cloud storage VIDEO file upload error: Error Domain=FIRStorageErrorDomain Code=-13000 "An unknown error occurred, please check the server response." UserInfo={object=PBY7Ost7nPWD8jWWF4qG.mov, ResponseBody=Can not finalize upload. Current size is 1692167. Expected final size is 1665242 ., bucket=launch-me-47860.appspot.com, data={length = 83, bytes = 0x43616e20 6e6f7420 66696e61 6c697a65 ... 31363635 3234322e }, data_content_type=text/plain; charset=utf-8, NSLocalizedDescription=An unknown error occurred, please check the server response., ResponseErrorDomain=com.google.HTTPStatus, ResponseErrorCode=400}

I have found similar questions posted from 2016 and 2017 but this Firebase write problem seems different as the initial upload always works and then the next time I try to perform an upload it fails with the error.

I added a routine to try additional upload attempts if the first upload fails. They all fail. Here is the upload code:

    // MARK: Write file to Firebase Cloud Storage
    private func fbCloudFileWrite(indexName: String) {
        let fbStorage = Storage.storage()
        print("(DEBUG FB) fbCloudFileWrite: upload indexName.csv and indexName.mov")
        // now upload file to cloud FireStore
        let fbStorageRef = fbStorage.reference()
        // Create a reference to the file you want to upload
        //let LaunchMeDataRef = fbStorageRef.child("LaunchMe/" + indexName + ".csv")
        //let LaunchMeVideoRef = fbStorageRef.child("LaunchMe/" + indexName + ".mov")
        var LaunchMeDataRef = fbStorageRef.child(indexName + ".csv")
        var LaunchMeVideoRef = fbStorageRef.child(indexName + ".mov")
        // Upload the file to the path "images/rivers.jpg"
        fbWriteAttempts += 1
        DispatchQueue.main.async {
            print("(DEBUG FB) ***** write attemp #: \(self.fbWriteAttempts)")
            if let vURL = self.videoURL, let dURL = self.dataFileURL {
                let uploadVideoTask = LaunchMeVideoRef.putFile(from: vURL, metadata: nil) { metadata, err in
                    if let err = err {
                        print("(DEBUG FB) cloud storage VIDEO file upload error: \(err)")
                        if self.fbWriteAttempts < 4 {
                            self.fbCloudFileWrite(indexName: indexName)
                        }
                    } else {
                        print("(DEBUG FB) video uploaded: \(indexName)")
                        let uploadDataTask = LaunchMeDataRef.putFile(from: dURL, metadata: nil) { metadata, err in
                            if let err = err {
                                print("(DEBUG FB) cloud storage SENSOR file upload error: \(err)")
                            } else {
                                print("(DEBUG FB) sensor data uploaded: \(indexName)")
                                print("(DEBUG FB) set newRecording = false to prevent duplicates")
                                // all files successfully uploaded. Set newRecording to false
                                self.newRecording = false
                            }
                        } // close uploadDataTask
                    } // close else
                } // close let uploadVideoTask
            } // close vURL unwrap
            else {
                print("(DEBUG FB) videoURL could not be unwrapped")
            }
        } // close Dispatch.main.async

Answer 1

Strangely enough, I was able to solve this problem by setting the URL variable of the movie local directory path within the VideoPlayerViewController instead of passing the URL in from the previous controller during the segue. This makes no sense to me that this would be necessary except perhaps some caching that happens behind the scenes.

I know the correct URL is passed in as the correct video plays on the screen when it is passed in, yet the Firebase Storage upload tries to upload the previous video (hence the expected size error) when provided the same URL that played the correct video.

New function added within the controller that sets the URL instead of passing it in (prior to performing the Firebase Storage upload):

private func setVideoStorageURL() {
        let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
        let path = "output.mov"
        videoURL = paths[0].appendingPathComponent(path)
    }

whereas the previous implementation that was not working passed the URL into the controller:

if let destinationVC = segue.destination as? VideoPlayerViewController {
                print("(DEBUG) Setting data to be passed to VideoPlayerViewController")
                destinationVC.newRecording = newRecording
                //now set newRecording to false if it is true
                if newRecording {
                    newRecording = false
                }
                destinationVC.audioMode = audioMode
                destinationVC.selectedDevice = selectedDevice
                destinationVC.videoURL = passFileURL