Merge pull request #31 from mfojtik/centos-base-tweaks

Refactoring of the centos-ruby-* images to share code and avoid duplication

Author: smarterclayton

centos-ruby-builder/Dockerfile

@@ -16,21 +16,14 @@
 FROM openshift/centos-ruby
 MAINTAINER Michal Fojtik <[email protected]>
 
-# Set the user we want the Ruby application run under and set the
-# user HOME directory as Docker reset this to '/' [1]
-#
-# [1] https://github.com/dotcloud/docker/issues/2968
-#
-USER ruby
-ENV  HOME /opt/ruby
-ENV  PATH $HOME/bin:$PATH
-
-# Set the initial command to `build`. After the application image is built
-# then the command is replaced by `run`
-#
-ADD ./bin/build /opt/ruby/bin/start
-ADD ./bin/run   /opt/ruby/bin/run
+ADD ./bin       /opt/ruby/bin
 ADD ./etc       /opt/ruby/etc
 
+# The initial 'start' command will trigger an application build when it runs in
+# 'self-contained' builder context. After application is built, then this
+# command is replaced in final application image by the 'run' command.
+#
+RUN chown -R ruby:ruby /opt/ruby/bin
 
+USER ruby
 ENTRYPOINT ["/opt/ruby/bin/start"]

centos-ruby-builder/bin/build

@@ -0,0 +1,21 @@
+#!/bin/bash -e
+
+source ${HOME}/etc/sdk
+source ${HOME}/etc/helpers
+
+# Allow users to inspect/debug the builder image itself, by using:
+# $ docker run -i -t openshift/centos-ruby-builder --debug
+#
+[ "$1" == "--debug" ] && exec /bin/bash
+
+# If the /tmp/src is empty, then print usage and exit.
+(dir_is_empty /tmp/src) && print_usage_and_exit
+
+# Build the ruby application first
+#
+${HOME}/bin/prepare
+
+# Replace this script with the application runner at the end of the build.
+#
+echo "---> Build successful. Commit this image with: docker commit ${HOSTNAME} ruby-app"
+cp -f ${HOME}/bin/run ${HOME}/bin/start && exit

centos-ruby-builder/bin/run

@@ -1,22 +1,6 @@
 # Ruby builder helper functions
 #
 
-# Execute ENTRYPOINT commands using.
-# Note: This command exits after it finishes
-#
-function bundle_exec() {
-  exec /opt/ruby/bin/ruby_context bundle exec "$@"
-}
-
-# FIXME: You can't stop the bundler install for now, using SIGINT or Ctrl-C
-#        because it is not executed using 'exec'. The 'exec' replace the parent
-#        process with itself and so later command are not executed.
-#
-function bundle_install() {
-  BUNDLE_WITHOUT=${BUNDLE_WITHOUT:-"development:test"}
-  /opt/ruby/bin/ruby_context bundle install $@
-}
-
 function print_usage_and_exit() {
   echo
   echo "This image can build your Ruby source code."
@@ -30,7 +14,3 @@ function print_usage_and_exit() {
   echo
   exit
 }
-
-function is_puma_installed() {
-  grep ' puma ' Gemfile.lock >/dev/null
-}

centos-ruby-builder/bin/start

@@ -23,14 +23,21 @@ RUN yum update --assumeyes && \
 
 # Create 'ruby' account we will use to run Ruby application
 #
-RUN mkdir -p /opt/ruby/{gems,run,src} && \
+RUN mkdir -p /opt/ruby/{gems,run,src,bin} && \
       groupadd -r ruby -f -g 433 && \
-      useradd -u 431 -r -g ruby -d /opt/ruby -s /sbin/nologin -c "Ruby application" ruby && \
-      chown -R ruby:ruby /opt/ruby
+      useradd -u 431 -r -g ruby -d /opt/ruby -s /sbin/nologin -c "Ruby application" ruby
 
-ADD ./bin /usr/bin/
+ADD ./bin /opt/ruby/bin/
 ADD ./etc /opt/ruby/etc/
-RUN chmod +x /usr/bin/{prepare,run,ruby_context,save-artifacts,usage}
+
+# FIXME: The STI require all scripts in /usr/bin path, this layer is here to
+#        maintain backward compatibility
+#
+RUN cp -f /opt/ruby/bin/prepare /usr/bin/prepare && \
+    cp -f /opt/ruby/bin/run /usr/bin/run && \
+    cp -f /opt/ruby/bin/save-artifacts /usr/bin/save-artifacts
+
+RUN chown -R ruby:ruby /opt/ruby
 
 # Set the 'root' directory where this build will search for Gemfile and
 # config.ru.
@@ -42,6 +49,8 @@ RUN chmod +x /usr/bin/{prepare,run,ruby_context,save-artifacts,usage}
 # GIT repository. The default value is the root folder.
 #
 ENV APP_ROOT .
+ENV HOME     /opt/ruby
+ENV PATH     $HOME/bin:$PATH
 
 # FIXME: This might be a potential bug in STI where if we keep the USER
 # instruction here, the resulting application image will fail to run.
@@ -52,4 +61,4 @@ EXPOSE 9292
 
 # Display STI usage when invoked outside STI builder
 #
-CMD ["/usr/bin/usage"]
+CMD ["/opt/ruby/bin/usage"]

centos-ruby-builder/etc/helpers

@@ -1,32 +1,38 @@
 #!/bin/sh -e
 
-source /opt/ruby/etc/sdk
+source ${HOME}/etc/sdk
 
 restore_build_artifacts
 
-app_src_dir="/opt/ruby/src/"
-app_root_dir="${app_src_dir}${APP_ROOT:-.}"
-bundle_dir="/opt/ruby/bundle"
+app_runtime_dir="${HOME}/src"
+app_src_dir="/tmp/src"
 
-echo "Building your Ruby application"
+echo "---> Installing application source"
+cp -Rf ${app_src_dir}/* ${app_runtime_dir}/
 
-mkdir -p $app_src_dir
-cp -Rf /tmp/src/* ${app_src_dir}/
-
-cd $app_root_dir
+pushd "$app_runtime_dir/${APP_ROOT}" >/dev/null
+echo "---> Building your Ruby application from source"
 
 if [ -f Gemfile ]; then
-  echo "Installing dependencies using Bundler"
+  echo "---> Installing dependencies using Bundler"
+
   ADDTL_BUNDLE_ARGS=""
   if [ -f Gemfile.lock ]; then
     ADDTL_BUNDLE_ARGS="--deployment"
   fi
+
   if [[ "$RAILS_ENV" == "development" || "$RACK_ENV" == "development" ]]; then
     BUNDLE_WITHOUT=${BUNDLE_WITHOUT:-"test"}
   elif [[ "$RAILS_ENV" == "test" || "$RACK_ENV" == "test" ]]; then
     BUNDLE_WITHOUT=${BUNDLE_WITHOUT:-"development"}
   else
     BUNDLE_WITHOUT=${BUNDLE_WITHOUT:-"development:test"}
   fi
-  ruby_context "bundle install --path ${bundle_dir} ${ADDTL_BUNDLE_ARGS}"
+
+  bundle_install --path ${HOME}/bundle ${ADDTL_BUNDLE_ARGS}
 fi
+
+# TODO: Add `rake assets:precompile` step here for Rails applications
+# TODO: Add `rake db:migrate` if linked with DB container
+
+popd >/dev/null

centos-ruby-builder/etc/puma.cfg

@@ -2,19 +2,19 @@
 
 source /opt/ruby/etc/sdk
 
-export GEM_HOME=/opt/ruby/gems
-export GEMRC=/opt/ruby/etc/gemrc
+export GEM_HOME=${HOME}/gems
+export GEMRC=${HOME}/etc/gemrc
+export EXECJS_RUNTIME=Node
 
-export RUBY_BIN_DIR="/opt/rh/ruby193/root/usr/bin"
-export GEM_INSTALL_OPTS="--bindir ${RUBY_BIN_DIR}"
+function scl_env() {
+  /usr/bin/scl enable ruby193 nodejs010 "printenv $1"
+}
 
-# If NodeJS is installed in system, then enable it to allow Rails
-# assets to compile successfully
+# FIXME: This is required in order to 'exec' run ruby instead of
+#        'scl' command. This have to be fixed in SCL in (near) future.
 #
+vars=( PATH LD_LIBRARY_PATH PYTHONPATH PKG_CONFIG_PATH )
+for var in "${vars[@]}"; do export ${var}=$(scl_env "${var}"); done
 
-collections="ruby193 $(is_nodejs_installed && echo 'nodejs010')"
-
-# You can reference environment variables in Dockerfile RUN
-# command and they will be substituted here
-#
-exec /usr/bin/scl enable ${collections} "$(echo -n "$@" | envsubst)"
+cmd="$1" && shift
+exec "$cmd" "$@"

centos-ruby/Dockerfile

@@ -1,20 +1,25 @@
-#!/bin/bash
+#!/bin/bash -e
 
 source /opt/ruby/etc/sdk
 
-app_src_dir="/opt/ruby/src/"
-app_root_dir="${app_src_dir}${APP_ROOT:-.}"
+# The app_root_dir needs to be exported, so the Puma or other Ruby
+# application server can pick it up and use it as 'application root'
+#
+export app_root_dir="${HOME}/src/${APP_ROOT:-.}"
+
+export RACK_ENV=${RACK_ENV:-"production"}
+export RAILS_ENV=${RAILS_ENV:-"${RACK_ENV}"}
 
 cd $app_root_dir
 
-# Choose the best application server to use. If users have 'puma' in the
-# Gemfile, then start the Ruby application using puma.
-#
-# Otherwise fallback to 'rackup'
+# Allow users to inspect/debug the builder image itself, by using:
+# $ docker run -i -t openshift/centos-ruby-builder --debug
 #
+[ "$1" == "--debug" ] && exec /bin/bash
+
 if is_puma_installed; then
-  puma_cfg="/opt/ruby/etc/puma.cfg"
-  /usr/bin/ruby_context "bundle exec 'puma --config $puma_cfg'"
+  bundle_exec "puma --config ${HOME}/etc/puma.cfg"
 else
-  /usr/bin/ruby_context "bundle exec 'rackup'"
+  echo "You might consider adding 'puma' into your Gemfile."
+  bundle_exec "rackup -P ${HOME}/run/rack.pid --host 0.0.0.0"
 fi

centos-ruby/bin/prepare

@@ -1,4 +1,4 @@
 #!/bin/bash
 
-(cd base && docker build -t openshift/centos-ruby .)
-(cd extended && docker build -t openshift/centos-ruby-extended .)
+(docker build -t openshift/centos-ruby .)
+(cd ../centos-ruby-builder && docker build -t openshift/centos-ruby-builder .)

centos-ruby/bin/ruby_context

@@ -1,8 +1,6 @@
-environment 'production'
-pidfile     '/opt/ruby/run/puma.pid'
-state_path  '/opt/ruby/run/puma.state'
+environment ENV['RACK_ENV'] || ENV['RAILS_ENV'] || 'production'
+pidfile     "#{ENV['HOME']}/run/puma.pid"
+state_path  "#{ENV['HOME']}/run/puma.state"
 threads     0, 16
 workers     0
 bind        'tcp://0.0.0.0:9292'
-
-preload_app!

centos-ruby/bin/run

@@ -1,20 +1,33 @@
 function is_puma_installed() {
+  [ ! -f Gemfile.lock ] && return 1
   grep ' puma ' Gemfile.lock >/dev/null
 }
 
-function is_nodejs_installed() {
-  (/usr/bin/scl -l | grep nodejs010) >/dev/null
-}
-
 function restore_build_artifacts() {
   if [ -e /tmp/artifacts/gems.tgz ]; then
-    echo -n "Restoring build artifacts"
+    echo "Restoring build artifacts"
     pushd / >/dev/null
     tar zxf /tmp/artifacts/gems.tgz
     popd >/dev/null
   fi
 }
 
-function dir_not_empty() {
-  [ -n "$(ls -A "$1" 2>/dev/null)" ]
+function dir_is_empty() {
+  [ -z "$(ls -A "$1" 2>/dev/null)" ]
+}
+
+# Execute ENTRYPOINT commands using.
+# Note: This command exits after it finishes
+#
+function bundle_exec() {
+  exec ruby_context bundle exec "$@"
+}
+
+# FIXME: You can't stop the bundler install for now, using SIGINT or Ctrl-C
+#        because it is not executed using 'exec'. The 'exec' replace the parent
+#        process with itself and so later command are not executed.
+#
+function bundle_install() {
+  BUNDLE_WITHOUT=${BUNDLE_WITHOUT:-"development:test"}
+  ruby_context bundle install $@
 }