Cancelling ongoing file uploads

[RichardBruskiewich]

Is there a use case and is it feasible to allow data submitters to gracefully cancel an upload process? What happens if the "Done Upload" is not yet pressed and the user leaves the upload screen.

[RichardBruskiewich]

Our current design may actually keep an upload "going" after a browser window is closed (bug or feature?). There needs to be a more graceful, user-controlled mechanism. Is there a browser-mediated way of intercepting a "window closure event" within which a user may be prompted to "cancel" their upload (or just use it to cancel the upload).

[RichardBruskiewich]

Mechanism implemented!

However, we need to check if MPU uploads are cleanly cancelled (since an embedded exception is thrown inside the s3_client.upload_fileobj() call.