This repo contains the kannel dockerfile and a docker compose stack which includes smsbox and a fakesmsc for testing purposes.
To test it run docker-compose up
After everything is running you can inject a message by using the provided sms box.
curl -v "http://localhost:13013/cgi-bin/sendsms?username=tester&password=foobar&message=Test&to=1234"
It should be "delivered" using the fakesmsc problem so you will see it on the output from docker.