docker: Clean up build and actually copy over the code

I'm not sure how it was working before but we weren't copying the
application code into the container. This does that and moves things
around to better support development (only install when package files
are updated for example).

Dockerfile

@@ -1,21 +1,23 @@
-# syntax=docker/dockerfile:1
 ARG RUBY_VERSION=3.3.1
 
 FROM ruby:$RUBY_VERSION
 
-RUN apt-get update -qq && apt-get install -y postgresql-client
-WORKDIR /myapp
-COPY Gemfile /myapp/Gemfile
-COPY Gemfile.lock /myapp/Gemfile.lock
-COPY mruby_build_config.rb /myapp/mruby_build_config.rb
-RUN bundle install
+RUN apt-get update -qq && apt-get upgrade -y && \
+  apt-get install -y libcurl4 postgresql-client tmux && \
+  rm -rf /var/lib/apt/lists/* /var/cache/apt/archives/*
+
+# Update Rubygems and Bundler
+RUN \
+  gem update --system --no-document && \
+  gem install --no-document bundler
+
+WORKDIR /app
+COPY mruby_build_config.rb /app/mruby_build_config.rb
 
 # mruby
-RUN git clone https://github.com/mruby/mruby.git && cd mruby && git checkout 3.0.0 && MRUBY_CONFIG="/myapp/mruby_build_config.rb" rake && mv ./bin/mruby /usr/bin/mruby && /usr/bin/mruby -v
+RUN git clone https://github.com/mruby/mruby.git && cd mruby && git checkout 3.0.0 && MRUBY_CONFIG="/app/mruby_build_config.rb" rake && mv ./bin/mruby /usr/bin/mruby && /usr/bin/mruby -v
 
 # Overmind
-RUN apt-get install -y tmux
-
 ARG OVERMIND_VERSION=2.5.1
 RUN curl -sL "https://github.com/DarthSim/overmind/releases/download/v${OVERMIND_VERSION}/overmind-v${OVERMIND_VERSION}-linux-arm64.gz" -o overmind.gz \
     && gunzip overmind.gz \
@@ -30,10 +32,26 @@ RUN curl -sL https://github.com/nodenv/node-build/archive/master.tar.gz | tar xz
     corepack enable && \
     rm -rf /tmp/node-build-master
 
+# Install Ruby dependencies
+COPY Gemfile Gemfile.lock /app/
+RUN bundle install && \
+    bundle exec bootsnap precompile --gemfile && \
+    rm -rf ~/.bundle/ $BUNDLE_PATH/ruby/*/cache $BUNDLE_PATH/ruby/*/bundler/gems/*/.git
+
+# Copy application code
+COPY --link . .
+
+# Install NodeJS dependencies
+RUN npm install --package-lock-only
+
+# Precompile bootsnap code for faster boot times
+RUN \
+  bundle exec bootsnap precompile app/ lib/ && \
+  bundle exec rake assets:precompile && \
+  bundle binstubs --force bundler
+
 # Add a script to be executed every time the container starts.
-COPY entrypoint.sh /usr/bin/
-RUN chmod +x /usr/bin/entrypoint.sh
-ENTRYPOINT ["entrypoint.sh"]
+ENTRYPOINT ["/app/entrypoint.sh"]
 EXPOSE 3000
 
 ENV MRUBY_BIN=/usr/bin/mruby

Gemfile

@@ -14,6 +14,7 @@ gem "propshaft"
 gem "actionpack-page_caching"
 gem "active_model_serializers"
 gem "bigdecimal"
+gem "bootsnap", require: false
 gem "dotenv-rails"
 gem "honeybadger"
 gem "pagy"

Gemfile.lock

@@ -88,6 +88,8 @@ GEM
     base64 (0.2.0)
     benchmark-ips (2.13.0)
     bigdecimal (3.1.5)
+    bootsnap (1.18.3)
+      msgpack (~> 1.2)
     builder (3.2.4)
     capybara (3.39.2)
       addressable
@@ -204,6 +206,7 @@ GEM
     mini_histogram (0.3.1)
     mini_mime (1.1.5)
     minitest (5.21.1)
+    msgpack (1.7.2)
     multi_json (1.15.0)
     mutex_m (0.2.0)
     net-imap (0.4.9.1)
@@ -375,6 +378,7 @@ DEPENDENCIES
   actionpack-page_caching
   active_model_serializers
   bigdecimal
+  bootsnap
   cssbundling-rails
   cuprite
   derailed