rails 4.1.0 -- mina + unicorn + nginx

mina

# config/deploy.rb

require 'mina/bundler'
require 'mina/rails'
require 'mina/git'
require 'mina/rvm'

# ter_mode 这个要设置，不然在 mac 下输密码有问题
set :term_mode, nil
set :rvm_path, '/usr/local/rvm/bin/rvm'

set :domain, 'domain_name'
set :deploy_to, 'app_path'
set :repository, 'github_path'
set :branch, 'master'

# Manually create these paths in shared/ (eg: shared/config/database.yml) in your server.
# They will be linked in the 'deploy:link_shared_paths' step.
set :shared_paths, ['config/database.yml', 'log', 'pids/unicorn.pid']

# Optional settings:
  set :user, 'deployer'    # Username in the server to SSH to.
#   set :port, '30000'     # SSH port number.

# This task is the environment that is loaded for most commands, such as
# `mina deploy` or `mina rake`.

task :environment do
  # If you're using rbenv, use this to load the rbenv environment.
  # Be sure to commit your .rbenv-version to your repository.
  # invoke :'rbenv:load'

  # For those using RVM, use this to load an RVM version@gemset.
  invoke :'rvm:use[ruby 2.1.1]' # the ruby version
end

# Put any custom mkdir's in here for when `mina setup` is ran.
# For Rails apps, we'll make some of the shared paths that are shared between
# all releases.
task :setup => :environment do
  queue! %[mkdir -p "#{deploy_to}/shared/log"]
  queue! %[chmod g+rx,u+rwx "#{deploy_to}/shared/log"]

  queue! %[mkdir -p "#{deploy_to}/shared/config"]
  queue! %[chmod g+rx,u+rwx "#{deploy_to}/shared/config"]

  queue! %[touch "#{deploy_to}/shared/config/database.yml"]

  queue  %[echo "-----> Be sure to edit 'shared/config/database.yml'."]

  queue! %[mkdir -p "#{deploy_to}/shared/pids"]
  queue! %[chmod g+rx,u+rwx "#{deploy_to}/shared/pids"]

  queue! %[touch "#{deploy_to}/shared/pids/unicorn.pid"]

end

desc "Deploys the current version to the server."
task :deploy => :environment do
  deploy do
    # Put things that will set up an empty directory into a fully set-up
    # instance of your project.
    invoke :'git:clone'
    invoke :'deploy:link_shared_paths'
    invoke :'bundle:install'
    invoke :'rails:db_migrate'
    invoke :'rails:assets_precompile'

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

namespace :unicorn do
  set :unicorn_pid, "/var/www/deploytest/shared/pids/unicorn.pid"
  set :start_unicorn, %{
    cd #{deploy_to}/current && unicorn -c config/unicorn.rb -E production -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}"` && rm -rf "#{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

nginx

# /etc/nginx/conf.d/default.conf

upstream app {
    # Path to Unicorn SOCK file, as defined previously
    server unix:/tmp/.unicorn.sock fail_timeout=0;
}
server {
    listen 80;
    server_name localhost;

    # Application root, as defined previously
    root /var/www/deploytest/current/public;

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

    location @app {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;
        proxy_pass http://app;
    }

    error_page 500 502 503 504 /500.html;
    client_max_body_size 4G;
    keepalive_timeout 10;
}

unicorn

# config/unicorn.rb

worker_processes 4

working_directory "/path_to_app/current"

listen "/tmp/.unicorn.sock", :backlog => 64
listen 8080, :tcp_nopush => true

timeout 30

pid "/path_to_app/shared/pids/unicorn.pid"

stderr_path "/path_to_app/shared/log/unicorn.stderr.log"
stdout_path "/path_to_app/shared/log/unicorn.stdout.log"

preload_app true

GC.respond_to?(:copy_on_write_friendly=) and
  GC.copy_on_write_friendly = true

check_client_connection false



before_fork do |server, worker|
  old_pid = "/path_to_app/shared/pids/unicorn.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
      puts "Send 'QUIT' signal to unicorn error!"
    end
  end
end

after_fork do |server, worker|
  # per-process listener ports for debugging/admin/migrations
  # addr = "127.0.0.1:#{9293 + worker.nr}"
  # server.listen(addr, :tries => -1, :delay => 5, :tcp_nopush => true)

  # the following is *required* for Rails + "preload_app true",
  defined?(ActiveRecord::Base) and
    ActiveRecord::Base.establish_connection

  # if preload_app is true, then you may also want to check and
  # restart any other shared sockets/descriptors such as Memcached,
  # and Redis.  TokyoCabinet file handles are safe to reuse
  # between any number of forked children (assuming your kernel
  # correctly implements pread()/pwrite() system calls)
end

怎么样算热部署呢？这样Unicorn的restart还是会中断服务，我想你应该把restart的方式改成发送USR2 signal