Heroku takes care of deploying your application, providing a hostname (myapp.herokuapp.com) and SSL (access via HTTPS).
You need to make sure your web application can bind to the port assigned at runtime by Heroku, this is provided in the $PORT env variable.
The web layer is provided by Heroku so your app only need to accept HTTP requests.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…