puma_wrapper.sh.erb

#!/bin/bash
#
# Copyright:: Copyright (c) 2015 Gitlab.com
# Copyright:: Copyright (c) 2016 Amusement SMART, LLC
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

#This wrapper is meant to be invoked by omnibus-smart-mobile via Runit

# Let runit capture all script error messages
exec 2>&1

export JAVA_HOME="/opt/smart-mobile/embedded/jre"
export PATH="/opt/smart-mobile/embedded/jruby/bin:/opt/smart-mobile/embedded/bin:$PATH"

function assert_non_empty
{
  if [ -z "$(eval echo \$$1)" ] ; then
    echo "$0 error: \$$1 is empty"
    exit 1
  fi
}

function find_us_a_puma
{
  adopt ${current_pidfile}
  if [[ ${puma_pid} ]]; then
    echo "adopted existing puma ${puma_pid}"
    return
  fi

  adopt ${oldbin_pidfile}
  if [[ ${puma_pid} ]]; then
    echo "adopted existing oldbin puma ${puma_pid}"
    return
  fi

  echo "starting new puma"
  start_puma
  sleep ${puma_wait_start}

  adopt ${current_pidfile}
  if [[ ${puma_pid} ]]; then
    echo "adopted new puma ${puma_pid}"
    return
  fi

  echo "failed to start a new puma"
  exit
}

function wait_for_puma_to_exit
{
  while sleep ${puma_poll_alive}; do
    alive ${puma_pid} || break
  done
}

function adopt
{
  local pid=$(cat $1 2>/dev/null)
  if alive ${pid} && is_puma ${pid}; then
    readonly puma_pid=${pid}
  fi
}

function is_puma
{
  ps -p $1 -o args | grep -q puma
}

function alive
{
  kill -0 $1 > /dev/null 2>&1
}

function start_puma
{
  echo 'starting puma'
  chpst -P -Usmart-mobile -u smart-mobile /opt/smart-mobile/embedded/jruby/bin/bundle exec puma /opt/smart-mobile/embedded/smart-mobile-rails/config.ru -e production -C /opt/smart-mobile/embedded/smart-mobile-rails/config/puma.rb
}

function forward_signal
{
  echo "forwarding $1 to puma master ${unicorn_pid}"
  kill -$1 ${unicorn_pid}
}

function trap_signals
{
  # Forward all common runit signals except:
  # - HUP which we handle below;
  # - KILL which cannot be caught.
  for sig in STOP CONT ALRM INT QUIT USR1 USR2 TERM; do
    trap "forward_signal ${sig}" ${sig}
  done

  # Omnibus-ctl does not have a subcommand that sends USR2 but it can send HUP.
  # To allow for reloading puma from the command line, translate HUP to
  # USR2.
  trap "echo 'wrapper received HUP'; forward_signal SIGKILL" HUP
}

function main
{
  cd /opt/smart-mobile/embedded/smart-mobile-rails
  find_us_a_puma
  trap_signals
  wait_for_puma_to_exit
}

assert_non_empty current_pidfile
assert_non_empty user
assert_non_empty environment
assert_non_empty puma_rb

readonly oldbin_pidfile=${current_pidfile}.oldbin
readonly puma_wait_start=1 # time in seconds
readonly puma_poll_alive=1 # time in seconds

main
echo "wrapper for puma ${puma_pid} exiting"

sv-puma-run.sh.erb

#!/bin/sh

# Let runit capture all script error messages
exec 2>&1
umask 077

exec chpst -P -u root \
  /usr/bin/env \
    current_pidfile=<%= node['smart-mobile']['puma']['pidfile'] %> \
    rails_app=<%= @options[:rails_app] %> \
    user=<%= @options[:user] %> \
    environment='production' \
    puma_rb=<%= @options[:puma_rb] %> \
    /opt/smart-mobile/embedded/bin/puma-wrapper