This extension can be used to Login or Register in Opencart

Instructions:

Install VQmod from the link https://github.com/vqmod/vqmod/releases
For Installation Please follow the instructions in https://github.com/vqmod/vqmod/wiki/Installing-vQmod-on-OpenCart
Copy the paste these files in to your upload folder
Go to your Admin Page and Install the "SmartiApps Google Login" module
Edit this module and Paste you Google Client ID and secret key and Save it.
Run the Composer require google/apiclient:^2.0
Now we can Register or Login using your google login

For Google API Key:

1) Please visit https://cloud.google.com/console
2) Create a new project, If you don't have it already.
3) Please select APIs & services->Credentials
4) Create Credentials for OAuth Client ID -> Web application
5) Copy your call back URL from this exttension and Paste it to "Authorized redirect URIs"
6) Get your APP ID and secret Key