pythondockerfastapiuvicorn

Unable to run Uvicorn server/FastAPI app through Docker

I am new to computer networks and Docker, and I'm trying to deploy and run a small FastAPI app using Docker. The app works successfully when I run it locally with Uvicorn, but it fails to run when I try to deploy it using Docker. Below is the error message. My OS is windows. I receive:

src/main.py

from fastapi import FastAPI

app = FastAPI()

@app.get("/")
def read_root():
    return {"Hello": "World"}

Here is my Dockerfile

FROM python:3.10-slim

WORKDIR /code

COPY ./requirements.txt ./
RUN pip install --no-cache-dir -r requirements.txt

COPY ./src ./src

CMD ["uvicorn", "src.main:app", "--host", "0.0.0.0", "--port", "80", "--reload"]

Here are the commands I used in the terminal:

docker build -t fastapi-image . 
docker run --name fastapi-container -p 80:80 fastapi-image

here is my docker log:

INFO:     Will watch for changes in these directories: ['/code']
INFO:     Uvicorn running on http://0.0.0.0:80 (Press CTRL+C to quit)
INFO:     Started reloader process [1] using StatReload
INFO:     Started server process [8]
INFO:     Waiting for application startup.
INFO:     Application startup complete.

my file structure:

requirements.txt
Dockerfile
src
|--main.py

requirements.txt

fastapi
uvicorn
Solution

  • By replicating the issue, can see the result at localhost:80.

    See also these posts to know more about the differences between localhost and 0.0.0.0: