Is there any way to upload and install an magento 2.1.2 extension in offline mode without magento connect?
Base on my official development station, I did not have a internet connection to use composer or magento connect.
I found the solution
You can upload you extension file in the below path:
<magento_installation_path>/app/code/
after that, you must run below command to register extension:
php <magento_installation_path>/bin/magento setup:upgrade
and sometime require to recompile magento with below command.
php <magento_installation_path>/bin/magento setup:di:compile