PHP class to print documents using Google Cloud Print. First of all you have to add printers to Google Cloud Print using your Gmail account and Google Chrome browser. Follow the instructions on the following link to add printer to Google Cloud Print https://support.google.com/cloudprint/answer/1686197
The API documentation is available right here: https://developers.google.com/cloud-print/docs/proxyinterfaces
Update login information in example.php and see the results.