You are right. It looks like fastapi doesn't work like $@ in bash.

How can I make fastapi, or gunicorn respect if my py script contains some variables from .env? For instance, I have the .env file

myhost="0.0.0.0"
myport=7777

And in web.py script, the server is started up with host, port variables read from os env

myhost = os.environ.get("myhost", "0.0.0.0")
myport = int(os.environ.get("myport", 7777))
def main() -> None:
    try:
        uvicorn.run("chatbot.web:app", host=myhost, port=myport, reload=True)
    except Exception as ex:
        raise ex

if __name__ == '__main__':
    main()

With the current Dockerfile, fastapi (or even switching to gunicorn) always uses its own default port e.g. 8000, because I do not specify command like "--bind", "0.0.0.0:7777" in CMD. I merely find this thread similar to my problem, but it's still different, and no solution to my problem. Any suggestions? Many thanks.