I'm constantly getting this message in Flutter: 'Connection closed before full header was received', when calling to create a download url for an image from storage.
It takes very long for the images to download, as the url needs to be regenerated, because the tokens expire in a short amount of time.
I'm wondering if there's faster way to do this, especially to download multiple images quickly.
final images = await Amplify.Storage.getUrl(key: element.groupIconUrl);
AWS Amplify DA here
If you want to download the file with key, you can use the downloadFile function instead of getUrl
I don't know which version of the library that you are working with but with the latest stable version of the AWS Amplify, you can download a local copy of the file by doing the following by using path_provider package:
import 'dart:io';
import 'package:path_provider/path_provider.dart';
Future<void> downloadFile() async {
final documentsDir = await getApplicationDocumentsDirectory();
final filepath = documentsDir.path + '/example.txt';
final file = File(filepath);
try {
final result = await Amplify.Storage.downloadFile(
key: element.groupIconUrl,
local: file,
onProgress: (progress) {
safePrint('Fraction completed: ${progress.getFractionCompleted()}');
},
);
final contents = result.file.readAsStringSync();
// Or you can reference the file that is created above
// final contents = file.readAsStringSync();
safePrint('Downloaded contents: $contents');
} on StorageException catch (e) {
safePrint('Error downloading file: $e');
}
}
For more information, you can check the official documentation here.
Let me know if you have any further questions!
EDIT: Question: How to generate URL for images?
The AWS Amplify generates a signed URL for each user according to the level of access that they have. That is why you can (also should) not generate a URL and let it be. You can define the expiration date for it.
How I do it in my sample app is as the following. Each time when I have see the image in the screen, then I call for getting the URL. Also I cache the image so when I come back I can keep the previous reference to it.
So my answer is, do not fetch all the image urls, only get them when you use them.
