Discourse 1.8.3 Dockerfile

Dockerfile

FROM ruby:2.4

WORKDIR /usr/src/app

ENV RAILS_ENV=production \
  RUBY_GC_MALLOC_LIMIT=90000000 \
  RUBY_GLOBAL_METHOD_CACHE_SIZE=131072 \
  DISCOURSE_DB_HOST=postgres \
  DISCOURSE_REDIS_HOST=redis \
  DISCOURSE_SERVE_STATIC_ASSETS=true

RUN curl --silent --location https://deb.nodesource.com/setup_6.x | bash - \
  && echo "deb http://ftp.debian.org/debian jessie-backports main" >> /etc/apt/sources.list \
  && apt-get update \
  && apt-get install -y --no-install-recommends \
      advancecomp \
      autoconf \
      ghostscript \
      gsfonts \
      imagemagick \
      jhead \
      jpegoptim \
      libbz2-dev \
      libfreetype6-dev \
      libjpeg-dev \
      libjpeg-turbo-progs \
      libpq5=9.6.3-1~bpo8+1 \
      libpq-dev=9.6.3-1~bpo8+1 \
      libtiff-dev \
      libxml2 \
      nodejs \
      optipng \
      pkg-config \
      postgresql-client-9.6=9.6.3-1~bpo8+1

ARG GIFSICLE_VERSION=1.88
RUN cd /tmp \
  && curl -O http://www.lcdf.org/gifsicle/gifsicle-$GIFSICLE_VERSION.tar.gz \
  && tar zxf gifsicle-${GIFSICLE_VERSION}.tar.gz \
  && cd gifsicle-${GIFSICLE_VERSION} \
  && ./configure && make install \
  && rm -rf /tmp/gifsicle*

ARG PNGQUANT_VERSION=2.8.0
RUN cd /tmp \
  && git clone -b ${PNGQUANT_VERSION} --single-branch https://github.com/pornel/pngquant \
  && cd pngquant \
  && make && make install \
  && rm -rf /tmp/pngq*

RUN npm install svgo uglify-js@"<3" -g \
  && rm -rf /tmp/* \
  && rm -rf /var/lib/apt/lists/*

ARG DISCOURSE_VERSION=1.8.3
RUN git clone --branch v${DISCOURSE_VERSION} https://github.com/discourse/discourse.git . \
  && git remote set-branches --add origin tests-passed \
  && bundle config build.nokogiri --use-system-libraries

# install additional gems
#
# this expects a space-separated list of gem names
ARG DISCOURSE_ADDITIONAL_GEMS=
RUN if [ "$DISCOURSE_ADDITIONAL_GEMS" != "" ]; then \
        echo >> Gemfile ; \
        echo '### DISCOURSE_ADDITIONAL_GEMS' >> Gemfile ; \
        for GEM_NAME in $DISCOURSE_ADDITIONAL_GEMS; do \
            echo "gem \"$GEM_NAME\"" >> Gemfile ; \
        done; \
    fi

# run bundler
# deployment mode if no new gems added, normal mode otherwise
RUN if [ "$DISCOURSE_ADDITIONAL_GEMS" != "" ]; then \
        bundle install --without test --without development; \
    else \
        bundle install --deployment --without test --without development; \
    fi

# install discourse plugins
# assumptions: no spaces in URLs (urlencoding is a thing)
#
# this expects a git-cloneable link
ARG DISCOURSE_ADDITIONAL_PLUGINS=
RUN if [ "$DISCOURSE_ADDITIONAL_PLUGINS" != "" ]; then \
        cd plugins/; \
        for PACKAGE_LINK in $DISCOURSE_ADDITIONAL_PLUGINS; do \
            git clone "$PACKAGE_LINK"; \
        done; \
    fi

# Custom configuration
COPY puma.rb config/puma.rb

EXPOSE 3000
CMD ["bundle", "exec", "rails", "server", "-b", "0.0.0.0"]

puma.rb

if ENV['RAILS_ENV']=='production'

  # First, you need to change these below to your situation.
  APP_ROOT = '/usr/src/app'

  # Second, you can choose how many threads that you are going to run at same time.
  workers 4
  threads 4,16

  # Unless you know what you are changing, do not change them.
  bind  "unix://#{APP_ROOT}/tmp/sockets/puma.sock"
  stdout_redirect "#{APP_ROOT}/log/puma.log","#{APP_ROOT}/log/puma.err.log"
  pidfile "#{APP_ROOT}/tmp/pids/puma.pid"
  state_path "#{APP_ROOT}/tmp/pids/puma.state"
  daemonize false
  preload_app!

end

Full stack based on this docker-compose file, but with postgres:9.6-alpine and redis:3.2-alpine.

Run bash -c "sleep 3 && rake db:migrate assets:precompile" once.
Afterwards restore default command and start container normally.