Custom file names

[js3692]

User can now provide a hashing function to set a custom file name for each upload. When the hashing function is not provided, it defaults to a random Uid.

Example:

const fileNameFromUrl = (req) => {
    return req.url.replace(/\//g, '-');
}

server.datastore = new tus.FileStore({
    path: '/files',
    namingFunction: fileNameFromUrl
});

Assuming the POST request was made to /files, the file name will now be '-file'

[coveralls]

Coverage decreased (-53.4%) to 30.315% when pulling 52792aa on js3692:custom-filenames into 16fbee5 on tus:master.

[coveralls]

Coverage increased (+2.5%) to 86.22% when pulling c5f3a5f on js3692:custom-filenames into 16fbee5 on tus:master.

[bhstahl]

This was added just for that example hashing function from our convo on the issue, right? Maybe it should just match the non-whitespace (\S) rather than any alphanumeric character.

[js3692]

Yes, that was to match the example function from the issue. I think \S would be more concise too :)

[coveralls]

Coverage decreased (-30.4%) to 63.06% when pulling bb77f6e on js3692:custom-filenames into 74f3ac7 on tus:master.

[coveralls]

Coverage decreased (-1.0%) to 92.537% when pulling 3b6a64e on js3692:custom-filenames into 74f3ac7 on tus:master.

[coveralls]

Coverage increased (+0.8%) to 94.34% when pulling 5e3d145 on js3692:custom-filenames into 74f3ac7 on tus:master.

[coveralls]

Coverage increased (+0.8%) to 94.318% when pulling c504c55 on js3692:custom-filenames into 74f3ac7 on tus:master.

[coveralls]

Coverage increased (+0.8%) to 94.318% when pulling e5e6fd5 on js3692:custom-filenames into 74f3ac7 on tus:master.

[bhstahl]

These error code/messages should probably be constants, but I can do that in a separate PR :)

[bhstahl]

Thanks @js3692 !!

[avillarubia]

only renames to - hypen without extension. What I need is to save the file to its original name