[BUG] Ass considers an ID as valid, and crashes when it tries to load the corresponding file since it does not exist about ass HOT 3 CLOSED

As a solution, I manually removed this particular upload from the data.json file, and restarted ass.
So the problem is solved, but it could happen again in the future.
So either there was an error during the upload, but ass still considered the upload valid and complete and therefore wrote the upload to the data.json file, and was therefore trying to serve a file that didn't exist, or there was an error during a deletion, which caused the file to be deleted, but not the file entry to be deleted from the data.json file.

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Just to confirm your Issue, you're using Node 12 with Docker?? My Docker files specifically specify Node 14. If you're not using Docker, then you need to use Node 14 for ass (mentioned in the README for local installation method)

Re-read the issue and this doesn't apply, writing new comment

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an upload failed, and ass considers the ID passed in the URL as valid, and when it tries to upload the file corresponding to this ID

I'm not sure what you mean by this. The upload process saves the file to disk/wherever first, then generates the ID after. If the file save failed, the upload is reject()'d by Promise and nothing will get saved.

it may occur if you mistakenly delete the files in the uploads folder

My main reply to this is simply that hosts should not be touching the uploads folder (I know it's not a great solution but you can delete using the ShareX program by right-clicking an image -> Open -> Deletion URL).

With that said, this definitely should not crash and I will look into this.

in order to remove from the database an upload that did not finish correctly and did not create a file.

I get the idea but because of my prior notes this wouldn't apply.

or there was an error during a deletion, which caused the file to be deleted, but not the file entry to be deleted from the data.json file

Based on the Issue and how ass operates internally I think this must be what happened, though I'm not sure what would have caused it to fail.

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