The code contains sample mechanism of synchronization of application database content into Google Drive. Can be used to import and export content between user devices for specific application.
The application uses observer on database tables and updates local config.json file with table name and its last update time.
Import operation consists of saving local config.json and all json-serialized database table contents into Google Drive.
During the export operation the application checks whether remote (Google Drive) config.json already exists, and if it does - it downloads it, compares it with local config.json content and downloads proper database json backup files from Google Drive if each table update time is different in compared files.