Imports github.com/freechessclub/icsgo github.com/gorilla/handlers github.com/gorilla/websocket github.com/sendgrid/sendgrid-go github.com/sendgrid/sendgrid-go/helpers/mail github.com/sirupsen/logrus Standard library imports encoding/base64 encoding/json fmt net net/http net/http/httputil net/url os path strings sync sync/atomic time