upload same file two times, it will save two times, that's a bug, no matter how many times we upload, it should save once!

[brownchow]

I upload a file two time, it save the file two time with different hash prefix, that's a bug!

I think, before we upload a file, we should calculate the SHA1 or MD5 sum of the file, and then check if the file have uploaded alerady, if true, just return the same link, else generate a new link

[moshee]

The expected behavior you describe used to be the default behavior, but I changed it due to a user request long long ago. I may consider reverting if I can dig up why I changed it in the first place.