Well, there is kio-gdrive which should allow you to access Google Drive from all KDE/KF5 applications (including dolphin the file manager).
https://community.kde.org/KIO_GDrive
For Leap 42.2 it’s available in the KDE:Extra repository. (but it will be included in 42.3 directly in the standard repos)
http://software.opensuse.org//download.html?project=KDE%3AExtra&package=kio-gdrive