Hash specification #8
Description
The metadata attribute returned by some HTTP Api calls contains a hash attribute.
Its documentation is:
64 bit integer representing hash of the contents of the file can be used to determine if two files are the same or to monitor file contents for changes. Present only for files.
Unfortunately, there is no specification of the hash algorithm, so it is useless except to detect that the file was updated since the last time we got its metadata.
In my case, I'm synchronizing a large set of files (about 10 000) and trying to detect if a local file has been updated since its last synchronization by an app I do not control (so I have no way to delete a cached hash on modification). Of course I can simply use size and date attributes, but hash is there to have better accuracy, unfortunately, I found no way to compute the local file hash (I tried parts of SHA1, MD5, SHA256, or xxHash64 without success).
The workaround is to call the File.checksum endpoint for every file which is time consuming on my side and resource consuming on your side ...