copy docker image from one machine to another
docker save -o <path for generated tar file> <image name>
dockerfile example
FROM ubuntu:18.04
COPY . /app
RUN make /app
CMD python /app/app.py
dockerfile copy specific files
COPY ["__BUILD_NUMBER", "README.md", "gulpfile", "another_file", "./"]
All the files and folders, the last is destination
dockerfile run app cmd
RUN apt-get install python3
CMD echo "Hello world"
ENTRYPOINT echo "Hello world"