Set contentEncoding when uploading a file

[gsabater]

I can't find anything in this repo or Superbalist/flysystem-google-cloud-storage about this issue.
When I try to upload a file with the following code, i cannot set the content-encoding to gzip

\Storage::disk('gcs')
    ->getDriver()
    ->put('myfile.json', gzencode($json, 8), [
        'metadata' => [
            'contentType'     => 'text/plain',
            'ContentEncoding' => 'gzip'
        ]
    ]);

I have tried with ContentEncoding and Content-Encoding inside and outside the metadata array.
The content-type is set correctly but the encoding is not.

Thanks in advance

[gsabater]

Ok, sorry for bothering again, it was just a typo on my end, ContentEncoding needs to be camelcase with the first letter in lowercase.

'metadata' => [
   'contentType'     => 'text/plain',
   'contentEncoding' => 'gzip'
 ]

Closing and leaving the issue in case anyone has the same problem.
Thanks