Файл docker

FROM ubuntu:18.04
COPY . /app
RUN make /app
CMD python /app/app.py

$ docker build --build-arg some_variable_name=a_value

cat DockerFile.debian.foo | docker build -t debian.foo -

# getting base image from ubuntu
FROM ubuntu:18.04

RUN apt-get update

CMD ["echo", "HEY from docker image"]

FROM busybox
ENV foo /bar
WORKDIR ${foo}   # WORKDIR /bar
ADD . $foo       # ADD . /bar
COPY \$foo /quux # COPY $foo /quux