Imports github.com/eclipse/paho.mqtt.golang github.com/go-redis/redis/v8 github.com/go-sql-driver/mysql go.mongodb.org/mongo-driver/mongo go.mongodb.org/mongo-driver/mongo/options gorm.io/driver/mysql gorm.io/gorm Standard library imports context crypto/tls crypto/x509 fmt io/ioutil log math/rand time