unicorn.rb

require "queris"
# Sample verbose configuration file for Unicorn (not Rack)
#
# This configuration file documents many features of Unicorn
# that may not be needed for some applications. See
# http://unicorn.bogomips.org/examples/unicorn.conf.minimal.rb
# for a much simpler configuration file.
#
# See http://unicorn.bogomips.org/Unicorn/Configurator.html for complete
# documentation.

# Use at least one worker per core if you're on a dedicated server,
# more will usually help for _short_ waits on databases/caches.
worker_processes 20

# Help ensure your application will always spawn in the symlinked
# "current" directory that Capistrano sets up.
#working_directory "/path/to/app/current" # available in 0.94.0+

# listen on both a Unix domain socket and a TCP port,
# we use a shorter backlog for quicker failover when busy
listen "/tmp/nchapp_unicorn.sock", :backlog => 64
listen 9293, :tcp_nopush => true

# nuke workers after 30 seconds instead of 60 seconds (the default)
timeout 30

# feel free to point this anywhere accessible on the filesystem
pid "/tmp/nchapp_unicorn.pid"

# By default, the Unicorn logger will write to stderr.
# Additionally, some applications/frameworks log to stderr or stdout,
# so prevent them from going to /dev/null when daemonized here:
stderr_path "/var/log/nchapp/unicorn.stderr.log"
stdout_path "/var/log/nchapp/unicorn.stdout.log"

# combine Ruby 2.0.0+ with "preload_app true" for memory savings
preload_app true
GC.respond_to?(:copy_on_write_friendly=) and
  GC.copy_on_write_friendly = true

# Enable this flag to have unicorn test client connections by writing the
# beginning of the HTTP headers before calling the application.  This
# prevents calling the application for connections that have disconnected
# while queued.  This is only guaranteed to detect clients on the same
# host unicorn runs on, and unlikely to detect disconnects even on a
# fast LAN.
check_client_connection false

# local variable to guard against running a hook multiple times
run_once = true

before_fork do |server, worker|
  Queris.disconnect
  if run_once
    # do_something_once_here ...
    run_once = false # prevent from firing again
  end
end

after_fork do |server, worker|
  Queris.reconnect
  
  if worker.nr + 1 == server.worker_processes 
    #loaded last worker. kill old unicorn master if necessary
    begin 
      oldpid = File.read "#{server.pid}.oldbin"
      Process.kill(:QUIT, oldpid.to_i)
    rescue Errno::ENOENT
      #no problem
    end
  end
end