I have a simple application I want to dockerize. It is a simple API that works correctly when I run it on my machine and is accessible on http://127.0.0.1:8000/ This is the dockerfile I created
FROM python:3.6-slim-stretch
WORKDIR /code
COPY requirements.txt /code
RUN pip install -r requirements.txt --no-cache-dir
COPY . /code
CMD ["uvicorn", "main:app", "--reload"]
I then create the image using this command sudo docker build -t test .
And then run it this way sudo docker run -d -p 8000:8000 test
The problem is that I cant access it http://127.0.0.1:8000/ even though I don't know the problem
PS: when I check my container ports I get 0.0.0.0:8000->8000/tcp, :::8000->8000/tcp
I want to know what is causing this problem and how to fix it.
By default uvicorn listens on 127.0.0.1. 127.0.0.1 inside the container is private,it doesn't participate in portforwarding.
The solution is to do uvicorn --host 0.0.0.0, e.g.:
CMD ["uvicorn", "main:app", "--reload", "--host", "0.0.0.0"]
For an explanation of why this is the case, with diagrams, see https://pythonspeed.com/articles/docker-connection-refused/