Programming WebRTC: server starts with http

#book-programming-webrtc

Just started reading this and tried starting the server but it starts with http.

 code> npm start **signaling-server:** WARNING: Your server is using 'http', not 'https'. **signaling-server:** Some things might not work as expected. **signaling-server:** +0ms **signaling-server:** ** Serving from the www/ directory. ** 
code> env | grep LOCAL LOCALHOST_SSL_CERT=/Users/perty/Certs/localhost.crt export LOCALHOST_SSL_KEY=/Users/perty/Certs/localhost.key 

What am I missing that does not make it start with https?