Example files to configure Docker, Nginx, and Passenger on a DigitalOcean Droplet.

app.conf

server {
    # Establish port and server name
    listen 80;
    server_name <server name>;
    
    # Point Nginx to your app's static "public" directory
    root /home/app/<app name>/public;
    
    # Turn on Passenger
    passenger_enabled on;
    passenger_user app;
    
    # Specify which ruby version you're using
    passenger_ruby /usr/bin/ruby2.3;
}

config.ru

require_relative "app"

run Sinatra::Application

docker-compose.yml

# Specify Docker Compose version to use (3 is most current)
version: "3"
services:
  <app name>:
    build: .
    ports:
      - "80:80"

Dockerfile

FROM phusion/passenger-full:0.9.33

ENV HOME /root

CMD ["/sbin/my_init"]

RUN rm -f /etc/service/nginx/down
RUN rm /etc/nginx/sites-enabled/default

ADD app.conf /etc/nginx/sites-enabled/app.conf

WORKDIR /home/app/personalSite
COPY --chown=app:app . .

RUN bundle install --without development test
RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*