I am trying to upload a video to youtube using client library v3.
The v3 library is experimental and does not have much documentation (samples provided does not include
The code to upload a video looks like this.
$youtubeService->videos->insert($part, Google_Video $postBody, $optParams = array());
'part' is what you want the request to return. In this case that could just be status, which return information about the status of the upload.
The release of the Google PHP client library might be old, so you'll want to checkout the source at https://code.google.com/p/google-api-php-client/