How to save google drive file into local directory using google.picker API?

Below is my code snippet part of google drive API integration.

var picker = new FilePicker({
            apiKey: 'here_is_my_api_key',
            clientId: 'here_is_my_clientid',
            buttonEl: document.getElementById('<%= btnUploadPhotoGD.ClientID %>'),
            onClick: function (file) {
                link.title = file.title;
                link.url = file.alternateLink;
                linksAry.push({ "title": file.title, "url": file.alternateLink, "thumbnail": file.thumbnailLink });
                document.getElementById('<%= linkJSON.ClientID %>').value = JSON.stringify(linksAry);
                bindDriveTable();
            }
        });