rails + mina + unicorn

deploy.rake

# lib/tasks/deploy.rake
namespace :deploy do
  desc 'Deploy to staging environment'
  task :staging do
    exec 'mina deploy -f config/deploy/staging.rb'
  end
end

mina.rb

# config/deploy/staging.rb
require 'mina/bundler'
require 'mina/rails'
require 'mina/git'
require 'mina/rvm'

#                                                                        Config
# ==============================================================================
set :term_mode,       :system
set :rails_env,       'staging'

set :domain,          '50.56.204.208'
set :port,            37894

set :deploy_to,       "/home/apps/mfp/#{rails_env}"
set :app_path,        "#{deploy_to}/#{current_path}"

set :repository,      'git@goup.unfuddle.com:goup/mfp.git'
set :brach,           'master'

set :user,            'apps'
set :shared_paths,    ['public/static', 'tmp']
set :keep_releases,   5

#                                                                           RVM
# ==============================================================================
set :rvm_path, '/usr/local/rvm/scripts/rvm'

task :environment do
  invoke 'rvm:use[1.9.3]'
end

#                                                                    Setup task
# ==============================================================================
task :setup do
  queue! %{
    mkdir -p "#{deploy_to}/shared/tmp/pids"
  }
end

#                                                                   Deploy task
# ==============================================================================
desc "deploys the current version to the server."
task :deploy => :environment do
  deploy do
    invoke 'git:clone'
    invoke 'bundle:install'
    invoke 'rails:db_migrate'
    invoke 'rails:assets_precompile'
    invoke 'deploy:link_shared_paths'

    to :launch do
      invoke :'unicorn:restart'
    end
  end
end


#                                                                       Unicorn
# ==============================================================================
namespace :unicorn do
  set :unicorn_pid, "#{app_path}/tmp/pids/unicorn.pid"
  set :start_unicorn, %{
    cd #{app_path}
    bundle exec unicorn -c #{app_path}/config/unicorn/#{rails_env}.rb -E #{rails_env} -D
  }

#                                                                    Start task
# ------------------------------------------------------------------------------
  desc "Start unicorn"
  task :start => :environment do
    queue 'echo "-----> Start Unicorn"'
    queue! start_unicorn
  end

#                                                                     Stop task
# ------------------------------------------------------------------------------
  desc "Stop unicorn"
  task :stop do
    queue 'echo "-----> Stop Unicorn"'
    queue! %{
      test -s "#{unicorn_pid}" && kill -QUIT `cat "#{unicorn_pid}"` && echo "Stop Ok" && exit 0
      echo >&2 "Not running"
    }
  end

#                                                                  Restart task
# ------------------------------------------------------------------------------
  desc "Restart unicorn using 'upgrade'"
  task :restart => :environment do
    invoke 'unicorn:stop'
    invoke 'unicorn:start'
  end
end

unicorn.rb

# config/unicorn/staging.rb
app_path = "/home/apps/mfp/staging/current"

worker_processes   1
preload_app        true
timeout            180
listen             '127.0.0.1:9021'
user               'apps', 'apps'
working_directory  app_path
pid                "#{app_path}/tmp/pids/unicorn.pid"
stderr_path        "log/unicorn.log"
stdout_path        "log/unicorn.log"

before_fork do |server, worker|
  ActiveRecord::Base.connection.disconnect!

  old_pid = "#{server.config[:pid]}.oldbin"
  if File.exists?(old_pid) && server.pid != old_pid
    begin
      Process.kill("QUIT", File.read(old_pid).to_i)
    rescue Errno::ENOENT, Errno::ESRCH
      # someone else did our job for us
    end
  end
end

after_fork do |server, worker|
  ActiveRecord::Base.establish_connection
end

is good

It seems like the server doesn't stop instantly and the server tries to start before the server shuts down...

-----> Launching
-----> Stop Unicorn
Stop Ok
Not running
-----> Start Unicorn
master failed to start, check stderr log for details
! ERROR: Deploy failed.

Also I heard to achieve 100% uptime you should send signals instead of stopping and starting the unicorn instance.

@PatrickMA any solution to that?

@jumph4x : I just used https://blog.nicolai86.eu/posts/2012-11-28/zero-downtime-deployments-with-unicorn-and-supervisord/ (Use unicornherder). Maybe things have improved since then ?

Nitpick: line 19, brach should be branch :-)