image size reduction [ship:docker] (#260)

Dockerfile

@@ -2,36 +2,36 @@ FROM ruby:2.5.9-slim
 
 LABEL maintainer Travis CI GmbH <[email protected]>
 
-# packages required for bundle install
 RUN ( \
-   apt-get update ; \
-   # update to deb 10.8
-   apt-get upgrade -y ; \
-   apt-get install -y --no-install-recommends git make gcc g++ libpq-dev curl \
-   && rm -rf /var/lib/apt/lists/* \
-)
-
-RUN ( \
-   curl -sLO http://ppa.launchpad.net/rmescandon/yq/ubuntu/pool/main/y/yq/yq_3.1-2_amd64.deb && \
-   dpkg -i yq_3.1-2_amd64.deb && \
-   rm -f yq_3.1-2_amd64.deb; \
+   bundle config set no-cache 'true'; \
+   bundle config --global frozen 1; \
+   bundle config set deployment 'true'; \
+   mkdir -p /app; \
 )
 
-RUN gem install bundler -v '2.3.7'
-
-# throw errors if Gemfile has been modified since Gemfile.lock
-RUN bundle config --global frozen 1
-
-RUN mkdir -p /app
 WORKDIR /app
 
 COPY Gemfile      /app
 COPY Gemfile.lock /app
-
 ARG bundle_gems__contribsys__com
-RUN bundle config https://gems.contribsys.com/ $bundle_gems__contribsys__com \
+
+RUN ( \
+   apt-get update ; \
+   apt-get upgrade -y ; \
+   apt-get install -y git make gcc g++ libpq-dev curl \
+   && rm -rf /var/lib/apt/lists/*; \
+   curl -sLO http://ppa.launchpad.net/rmescandon/yq/ubuntu/pool/main/y/yq/yq_3.1-2_amd64.deb && \
+   dpkg -i yq_3.1-2_amd64.deb && \
+   rm -f yq_3.1-2_amd64.deb; \
+   gem install bundler -v '2.3.14'; \
+   bundle config https://gems.contribsys.com/ $bundle_gems__contribsys__com \
       && bundle install --deployment \
-      && bundle config --delete https://gems.contribsys.com/
-RUN gem install --user-install executable-hooks
+      && bundle config --delete https://gems.contribsys.com/; \
+   apt-get remove -y gcc g++ make git perl && apt-get -y autoremove; \
+   bundle clean && rm -rf /app/vendor/bundle/ruby/2.5.0/cache/*; \
+   rm -rf /usr/local/bundle/cache/\*.gem; \
+   find /usr/local/bundle/gems/ \( -name '*.c' -o -name '*.h' -o -name '*.cpp' -o -name '*.o' \) -delete; \
+   find /app/vendor/ \( -name '*.c' -o -name '*.h' -o -name '*.cpp' -o -name '*.o' \) -delete; \
+)
 
 COPY . /app

Makefile

@@ -31,7 +31,7 @@ DOCKER ?= docker
 
 .PHONY: docker-build
 docker-build:
-	$(DOCKER) build --build-arg bundle_gems__contribsys__com=$(BUNDLE_GEMS__CONTRIBSYS__COM) -t $(DOCKER_DEST) .
+	$(DOCKER) build --pull --no-cache --build-arg bundle_gems__contribsys__com=$(BUNDLE_GEMS__CONTRIBSYS__COM) -t $(DOCKER_DEST) .
 
 .PHONY: docker-login
 docker-login: