docker build
docker build -t [tag] .
how to create docker image from custom filename
cat DockerFile.debian.foo | docker build -t debian.foo -
docker build from dockerfile
$ docker build - < Dockerfile
create dockerfile
FROM ubuntu:18.04
COPY . /app
RUN make /app
CMD python /app/app.py
docker build specify dockerfile
docker build -t [name] -f [Dockerfile]