Dockerfile of Open AI universe

Recently I have tried to build a docker file of Open AI’s universe. I found two interesting things in universe’s Dockerfile.

Cachebusting

# Cachebusting
COPY ./setup.py ./
COPY ./tox.ini ./

RUN pip install -e .

# Upload our actual code
COPY . ./

In Dockerfile, the configuration files of package dependency are copied first. And Dependent packages are installed, then all source code are copied. I think it is for docker image layer and it can be applied to my python project as well.

In my project, I copied all source files and installed packages using pipenv. I’m going to modify Pipfile and Pipfile.lock to copy first.

py3clean

# Just in case any python cache files were carried over from
# the source directory, remove them
RUN py3clean .

In universe Dockerfile, run the command py3clean at the end. I’ve never seen this command before. It is said to delete python cache files. I compared the file size of docker image with this command or not. The difference in file size was only 2bytes.

I think this small difference may be because the source codes have never been run at my local PC. The command py3clean is installed for python installation in ubuntu, so it might not be bad to add it to Dockerfile.