Show file upload speed - firebase

Question

Is it possible to show for user upload speed?
I'm uploading file (video) to Firebase. File is so large (approx. 2GB).
Can I show for user currently upload speed for that file?

Answer 1

It's pretty similar to how you are showing the progress. If you are showing the progress that means you can access the bytesTransferred property. now you just need to calculate the speed by using that property. There could be a better or more optimized way to do this but this is how I do it.
int lastBytesTransferred = 0;
DateTime? lastBytesTransferredTime;
// to make sure the speed only updates once in an interval and not every millisecond or so
Duration updateDurationThreshold = const Duration(seconds: 2);
double speed = 0;
UploadTask task =
FirebaseStorage.instance.ref().child("files/$fileName").putData(file!);
task.snapshotEvents.listen((event) {
if (lastBytesTransferredTime == null) {
lastBytesTransferred = event.bytesTransferred;
lastBytesTransferredTime = DateTime.now();
speed = 0;
} else {
final now = DateTime.now();
final Duration duration = now.difference(lastBytesTransferredTime!);
if (duration > updateDurationThreshold) {
final double bytesPerSecond =
(event.bytesTransferred - lastBytesTransferred) /
duration.inSeconds;
lastBytesTransferred = event.bytesTransferred;
lastBytesTransferredTime = now;
setState(() {
speed = bytesPerSecond / 1024; // in kbps
});
}
}
});

Answer 2

The Firebase SDKs report progress for file uploads to Cloud Storage, which you can use to calculate the upload speed. In Flutter you can listen for upload events, as shown in the second code sample in the documentation on handling upload tasks. From there:
for larger files it may be a better user experience if a progress indicator can be shown. Tasks can also provide a stream of events, which emits a TaskSnapshot each time a notable event occurs (e.g. upload progress). The snapshot provides information about the state of the task along with the amount of bytes that have been processed:
Future<void> handleTaskExample2(String filePath) async {
File largeFile = File(filePath);
firebase_storage.UploadTask task = firebase_storage.FirebaseStorage.instance
.ref('uploads/hello-world.txt')
.putFile(largeFile);
task.snapshotEvents.listen((firebase_storage.TaskSnapshot snapshot) {
print('Task state: ${snapshot.state}');
print(
'Progress: ${(snapshot.bytesTransferred / snapshot.totalBytes) * 100} %');
}, onError: (e) {
// The final snapshot is also available on the task via `.snapshot`,
// this can include 2 additional states, `TaskState.error` & `TaskState.canceled`
print(task.snapshot);
if (e.code == 'permission-denied') {
print('User does not have permission to upload to this reference.');
}
});
// We can still optionally use the Future alongside the stream.
try {
await task;
print('Upload complete.');
} on firebase_core.FirebaseException catch (e) {
if (e.code == 'permission-denied') {
print('User does not have permission to upload to this reference.');
}
// ...
}
}