Cannot connect to fast api server at localhost:8000 from my application which is running under a docker container

Question

I a newbie to working with fastapi. I have a main.py inside docker container.When I connect to fastapi using

uvicorn main:app —-reload 

from my container.I am prompted to connect to http://127.0.0.1:8000. On copying the address to Firefox I am getting the error:

 unable to connect. 

How can I connect to fastapi server ?

P.S The git branch I am working from was developed by another colleague so I have little to no idea how was fastapi was set up inside the docker

Answer 1

You need to use the command

uvicorn main:app --reload --host 0.0.0.0

Your docker container is like a computer, which is independent. Thus it does not allow access from external sources. With the --host option, you allow external connections (outside of localhost from the point of view of the container). Basically, docker's localhost is different from your computer's localhost.