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@catuss-a
Created June 7, 2016 11:35
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app_name = "ldl-website"
root = "/var/www/#{app_name}/current"
pid "#{root}/tmp/pids/unicorn.pid"
stderr_path "#{root}/log/unicorn.error.log"
stdout_path "#{root}/log/unicorn.access.log"
listen "/tmp/unicorn.#{app_name}.sock", :backlog => 2048
preload_app true
working_directory root
worker_processes 2
timeout 30
before_fork do |server, worker|
# the following is highly recomended for Rails + "preload_app true"
# as there's no need for the master process to hold a connection
defined?(ActiveRecord::Base) and ActiveRecord::Base.connection.disconnect!
##
# 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.
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
defined?(ActiveRecord::Base) and 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 deployer:deployer
begin
uid, gid = Process.euid, Process.egid
user, group = 'deployer', 'deployer'
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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