Ruby Jupyter Notebook with persistent gems folder and jupyter token

docker-compose.yml

services:
  jupyter:
    build: .
    image: bibstha/datascience-notebook
    ports:
      - 80:8888
    environment:
      GEM_HOME: /home/jovyan/.gems
      RUBYLIB: /home/jovyan/.gems
      JUPYTER_TOKEN: this-is-my-token
    volumes:
      - jupyter-data:/home/jovyan/work
      - ./gems_cache:/home/jovyan/.gems

volumes:
  jupyter-data:
    name: jupyter-data
    
# I tried creating a named volume for gems but it was being mounted as root and the user is jovyan (no write permission)
# so I did `cd path-to-docker-compose && chown 1000:100 ./gems_cache`

# GEM_HOME makes it so that `gem install xyz` will install it to `/home/jovyan/.gems`
# RUBYLIB appends the folder to $LOAD_PATH so anything installed on GEM_HOME is loaded properly

# I also had to remove the .gemrc as I wanted gems to be installed into GEM_HOME. Therefore the custom Dockerfile below.

Dockerfile

FROM rubydata/datascience-notebook
RUN rm /home/jovyan/.gemrc

Put both docker-compose.yml and Dockerfile in a folder.
Run docker-compose up -d

Then open localhost:80 and enter token this-is-my-token. If you get permission error, try changing ports to 8080:8080 and load localhost:8080.