Setting up Nginx+Unicorn production server

gem 'unicorn'

sudo su -l

#!/bin/sh

# File: /etc/init.d/unicorn

### BEGIN INIT INFO
# Provides:          unicorn
# Required-Start:    $local_fs $remote_fs $network $syslog
# Required-Stop:     $local_fs $remote_fs $network $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: starts the unicorn web server
# Description:       starts unicorn
### END INIT INFO

# Feel free to change any of the following variables for your app:

# Set user
USER=deployer
# Set app name
APP_NAME=myflix

# Replace [PATH_TO_RAILS_ROOT_FOLDER] with your application's path.
APP_ROOT=/home/$USER/apps/$APP_NAME/current
# Set the environment. This can be changed to staging or development for staging
# servers.
RAILS_ENV=production
# This should match the pid setting in $APP_ROOT/config/unicorn.rb.
PID_FILE=$APP_ROOT/tmp/unicorn.pid
# A simple description for service output.
DESC="Unicorn app - $RAILS_ENV"
# If you're using rbenv, you may need to use the following setup to get things
# working properly:
RBENV_RUBY_VERSION=`cat $APP_ROOT/.ruby-version`
RBENV_ROOT="/home/$USER/.rbenv"
RBENV="$RBENV_ROOT/bin/rbenv"
PATH="$RBENV_ROOT/bin:$PATH"
SET_PATH="cd $APP_ROOT && $RBENV rehash && $RBENV local $RBENV_RUBY_VERSION"

# Unicorn can be run using `bundle exec unicorn` or `bin/unicorn`.
UNICORN="$RBENV_ROOT/shims/unicorn"
# Execute the unicorn executable as a daemon, with the appropriate configuration
# and in the appropriate environment.
UNICORN_OPTS="-c $APP_ROOT/config/unicorn.rb -E $RAILS_ENV -D"
CMD="$UNICORN $UNICORN_OPTS"

# Give your upgrade action a timeout of 60 seconds.
TIMEOUT=60

# Store the action that we should take from the service command's first
# argument (e.g. start, stop, upgrade).
action="$1"

# Make sure the script exits if any variables are unset. This is short for
# set -o nounset.
set -u

# Set the location of the old pid. The old pid is the process that is getting
# replaced.
old_pid="$PID_FILE.oldbin"

# Make sure the APP_ROOT is actually a folder that exists. An error message from
# the cd command will be displayed if it fails.
cd $APP_ROOT || exit 1

# A function to send a signal to the current unicorn master process.
sig () {
  test -s "$PID_FILE" && kill -$1 `cat $PID_FILE`
}

# Send a signal to the old process.
oldsig () {
  test -s $old_pid && kill -$1 `cat $old_pid`
}

# A switch for handling the possible actions to take on the unicorn process.
case $action in
  # Start the process by testing if it's there (sig 0), failing if it is,
  # otherwise running the command as specified above.
  start)
    sig 0 && echo >&2 "$DESC is already running" && exit 0
    su - $USER -c "$CMD"
    ;;

  # Graceful shutdown. Send QUIT signal to the process. Requests will be
  # completed before the processes are terminated.
  stop)
    sig QUIT && echo "Stopping $DESC" exit 0
    echo >&2 "Not running"
    ;;

  # Quick shutdown - kills all workers immediately.
  force-stop)
    sig TERM && echo "Force-stopping $DESC" && exit 0
    echo >&2 "Not running"
    ;;

  # Graceful shutdown and then start.
  restart)
    sig QUIT && echo "Restarting $DESC" && sleep 2 \
      && su - $USER -c "$CMD" && exit 0
    echo >&2 "Couldn't restart."
    ;;

  # Reloads config file (unicorn.rb) and gracefully restarts all workers. This
  # command won't pick up application code changes if you have `preload_app
  # true` in your unicorn.rb config file.
  reload)
    sig HUP && echo "Reloading configuration for $DESC" && exit 0
    echo >&2 "Couldn't reload configuration."
    ;;

  # Re-execute the running binary, then gracefully shutdown old process. This
  # command allows you to have zero-downtime deployments. The application may
  # spin for a minute, but at least the user doesn't get a 500 error page or
  # the like. Unicorn interprets the USR2 signal as a request to start a new
  # master process and phase out the old worker processes. If the upgrade fails
  # for some reason, a new process is started.
  upgrade)
    if sig USR2 && echo "Upgrading $DESC" && sleep 10 \
      && sig 0 && oldsig QUIT
    then
      n=$TIMEOUT
      while test -s $old_pid && test $n -ge 0
      do
        printf '.' && sleep 1 && n=$(( $n - 1 ))
      done
      echo

      if test $n -lt 0 && test -s $old_pid
      then
        echo >&2 "$old_pid still exists after $TIMEOUT seconds"
        exit 1
      fi
      exit 0
    fi
    echo >&2 "Couldn't upgrade, starting 'su - $USER -c \"$CMD\"' instead"
    su - $USER -c "$CMD"
    ;;

  # A basic status checker. Just checks if the master process is responding to
  # the `kill` command.
  status)
    sig 0 && echo >&2 "$DESC is running." && exit 0
    echo >&2 "$DESC is not running."
    ;;

  # Reopen all logs owned by the master and all workers.
  reopen-logs)
    sig USR1
    ;;

  # Any other action gets the usage message.
  *)
    # Usage
    echo >&2 "Usage: $0 <start|stop|restart|reload|upgrade|force-stop|reopen-logs>"
    exit 1
    ;;
esac

chmod +x /etc/init.d/unicorn
update-rc.d unicorn defaults
service unicorn restart

# Set the current app's path for later reference. Rails.root isn't available at
# this point, so we have to point up a directory.
app_path = File.expand_path(File.dirname(__FILE__) + '/..')

# The number of worker processes you have here should equal the number of CPU cores your server has.
worker_processes (ENV['RAILS_ENV'] == 'production' ? 2 : 1)

# You can listen on a port or a socket. Listening on a socket is good in a
# production environment, but listening on a port can be useful for local
# debugging purposes.
listen app_path + '/tmp/unicorn.sock', backlog: 64

# For development, you may want to listen on port 3000 so that you can make sure
# your unicorn.rb file is soundly configured.
listen(3000, backlog: 64) if ENV['RAILS_ENV'] == 'development'
# After the timeout is exhausted, the unicorn worker will be killed and a new
# one brought up in its place. Adjust this to your application's needs. The
# default timeout is 60. Anything under 3 seconds won't work properly.
timeout 60

# Set the working directory of this unicorn instance.
working_directory app_path

# Set the location of the unicorn pid file. This should match what we put in the
# unicorn init script later.
pid app_path + '/tmp/unicorn.pid'

# You should define your stderr and stdout here. If you don't, stderr defaults
# to /dev/null and you'll lose any error logging when in daemon mode.
stderr_path app_path + '/log/unicorn.log'
stdout_path app_path + '/log/unicorn.log'

# Load the app up before forking.
preload_app true

# Garbage collection settings.
GC.respond_to?(:copy_on_write_friendly=) &&
  GC.copy_on_write_friendly = true

# If using ActiveRecord, disconnect (from the database) before forking.
before_fork do |server, worker|
  defined?(ActiveRecord::Base) &&
    ActiveRecord::Base.connection.disconnect!
end

# After forking, restore your ActiveRecord connection.
after_fork do |server, worker|
  defined?(ActiveRecord::Base) &&
    ActiveRecord::Base.establish_connection
end

apt-get install nginx

# Run nginx as www-data.
user www-data;
# One worker process per CPU core is a good guideline.
worker_processes 1;

pid /var/run/nginx.pid;

# For a single core server, 1024 is a good starting point. Use `ulimit -n` to
# determine if your server can handle more.
events {
    worker_connections 1024;
}

http {

  ##
  # Basic Settings
  ##

  sendfile on;
  tcp_nopush on;
  tcp_nodelay off;
  keepalive_timeout 65;
  types_hash_max_size 2048;
  server_tokens off;

  include /etc/nginx/mime.types;
  default_type application/octet-stream;

  ##
  # Logging Settings
  ##

  access_log /var/log/nginx/access.log;
  error_log /var/log/nginx/error.log;

  ##
  # Gzip Settings
  ##

  gzip on;
  gzip_disable "msie6";
  gzip_http_version 1.1;
  gzip_proxied any;
  gzip_min_length 500;
  gzip_types text/plain text/xml text/css
    text/comma-separated-values text/javascript
    application/x-javascript application/atom+xml;

  ##
  # Unicorn Rails
  ##

  # The socket here must match the socket path that you set up in unicorn.rb.
  upstream unicorn {
    server unix:/home/deployer/apps/myflix/current/tmp/unicorn.sock fail_timeout=0;
  }

  ##
  # Virtual Host Configs
  ##

  include /etc/nginx/conf.d/*.conf;
  include /etc/nginx/sites-enabled/*;
}

server {
  listen 80;
  server_name myflix.com; # Set server name

  keepalive_timeout 300;

  client_max_body_size 4G;

  root /home/deployer/apps/myflix/current/public; # Set this to the public folder location of your Rails application.

  try_files $uri/index.html $uri.html $uri @unicorn;

  location @unicorn {
          proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
          proxy_set_header Host $http_host;
          proxy_set_header X-Forwarded_Proto $scheme;
          proxy_redirect off;
          # This passes requests to unicorn, as defined in /etc/nginx/nginx.conf
          proxy_pass http://unicorn;
          proxy_read_timeout 300s;
          proxy_send_timeout 300s;
  }

  # You can override error pages by redirecting the requests to a file in your
  # application's public folder, if you so desire:
  error_page 500 502 503 504 /500.html;
  location = /500.html {
          root /home/deployer/apps/myflix/current/public;
  }
}

cd /etc/nginx/sites-enabled
rm default
ln -s ../sites-available/myflix myflix
service nginx restart