Could Not Locate A Flask Application When Creating A Docker Image

I hope someone can help me with this. The following error code comes up when I try and run docker run todolist-docker. WARNING: This is a development server. Do not use it in a

Solution 1:

Is FLASK_APP defined in the docker container? There's no ENV statement in the Dockerfile, and you didn't mention using docker's -e or --env command option. Your container won't inherit your environment variables from the hosting environment.

# syntax=docker/dockerfile:1

FROM python:3.7.8

WORKDIR /tododocker

COPY requirements.txt requirements.txt
RUN pip3 install -r requirements.txt

COPY . .
# Add this:
ENV FLASK_APP=App.py

CMD [ "python3", "-m" , "flask", "run", "--host=0.0.0.0"]