Create DockerFile

We will now create a DockerFile that builds a Docker image. The image contains all the dependencies the Python application requires, including Python itself.

In the project directory, create a file named DockerFile

FROM python:3.7-alpine
WORKDIR /code
ENV FLASK_APP app.py
ENV FLASK_RUN_HOST 0.0.0.0
COPY requirements.txt requirements.txt 
RUN pip install -r requirements.txt
COPY . .
CMD ["flask","run"]

This tells Docker to:

• Build an image starting with the Python 3.7 image.
• Set the working directory to /code.
• Set environment variables used by the flask command.
• Copy requirements.txt and install the Python dependencies.
• Copy the current directory . in the project to the workdir . in the image.
• Set the default command for the container to flask run.