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@rrouse
Last active December 18, 2015 03:29
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task :stop, :roles => :app do
run "kill -QUIT `cat #{shared_path}/pids/unicorn.pid`"
end
desc "Restart app server"
task :restart, :roles => :app do
run "kill -USR2 `cat #{shared_path}/pids/unicorn.pid`"
end
task :start, :roles => :app do
run "cd #{current_path} && bundle exec unicorn -Dc #{current_path}/config/unicorn.rb -E #{stage}"
end
# unicorn_rails -c config/unicorn.rb -E production -D
root = ENV['PWD']
rails_env = ENV['RAILS_ENV'] || 'production'
worker_processes 6
# Load rails+github.git into the master before forking workers
# for super-fast worker spawn times
preload_app true
# Restart any workers that haven't responded in 30 seconds
timeout 30
listen root + "/tmp/pids/unicorn.sock", :backlog => 64
pid root + "/tmp/pids/unicorn.pid"
##
# REE
# http://www.rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
if GC.respond_to?(:copy_on_write_friendly=)
GC.copy_on_write_friendly = true
end
before_fork do |server, worker|
##
# When sent a USR2, Unicorn will suffix its pidfile with .oldbin and
# immediately start loading up a new version of itself (loaded with a new
# version of our app). When this new Unicorn is completely loaded
# it will begin spawning workers. The first worker spawned will check to
# see if an .oldbin pidfile exists. If so, this means we've just booted up
# a new Unicorn and need to tell the old one that it can now die. To do so
# we send it a QUIT.
#
# Using this method we get 0 downtime deploys.
ActiveRecord::Base.connection.disconnect!
old_pid = root + '/tmp/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
# someone else did our job for us
end
end
end
after_fork do |server, worker|
##
# Unicorn master loads the app then forks off workers - because of the way
# Unix forking works, we need to make sure we aren't using any of the parent's
# sockets, e.g. db connection
ActiveRecord::Base.establish_connection
# Redis and Memcached would go here but their connections are established
# on demand, so the master never opens a socket
##
# Unicorn master is started as root, which is fine, but let's
# drop the workers to git:git
begin
uid, gid = Process.euid, Process.egid
user, group = 'shasta', 'shasta'
target_uid = Etc.getpwnam(user).uid
target_gid = Etc.getgrnam(group).gid
worker.tmp.chown(target_uid, target_gid)
if uid != target_uid || gid != target_gid
Process.initgroups(user, target_gid)
Process::GID.change_privilege(target_gid)
Process::UID.change_privilege(target_uid)
end
rescue => e
if rails_env == 'development'
STDERR.puts "couldn't change user, oh well"
else
raise e
end
end
end
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