Class: Unicorn::Configurator
- Inherits:
-
Struct
- Object
- Struct
- Unicorn::Configurator
- Defined in:
- lib/unicorn/configurator.rb
Overview
Implements a simple DSL for configuring a Unicorn server.
Example (when used with the unicorn config file):
worker_processes 4
working_directory "/path/to/deploy/app/current"
listen '/tmp/my_app.sock', :backlog => 1
listen 9292, :tcp_nopush => true
timeout 10
pid "/tmp/my_app.pid"
# combine REE with "preload_app true" for memory savings
# http://rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
preload_app true
GC.respond_to?(:copy_on_write_friendly=) and
GC.copy_on_write_friendly = true
before_fork do |server, worker|
# the following is 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!
# the following allows a new master process to incrementally
# phase out the old master process with SIGTTOU to avoid a
# thundering herd (especially in the "preload_app false" case)
# when doing a transparent upgrade. The last worker spawned
# will then kill off the old master process with a SIGQUIT.
old_pid = "#{server.config[:pid]}.oldbin"
if old_pid != server.pid
begin
sig = (worker.nr + 1) >= server.worker_processes ? :QUIT : :TTOU
Process.kill(sig, File.read(old_pid).to_i)
rescue Errno::ENOENT, Errno::ESRCH
end
end
# optionally throttle the master from forking too quickly by sleeping
sleep 1
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
Constant Summary collapse
- DEFAULTS =
Default settings for Unicorn
{ :timeout => 60, :logger => Logger.new($stderr), :worker_processes => 1, :after_fork => lambda { |server, worker| server.logger.info("worker=#{worker.nr} spawned pid=#{$$}") }, :before_fork => lambda { |server, worker| server.logger.info("worker=#{worker.nr} spawning...") }, :before_exec => lambda { |server| server.logger.info("forked child re-executing...") }, :pid => nil, :preload_app => false, }
Instance Attribute Summary collapse
-
#config_file ⇒ Object
Returns the value of attribute config_file.
-
#set ⇒ Object
Returns the value of attribute set.
Instance Method Summary collapse
-
#[](key) ⇒ Object
:nodoc:.
-
#after_fork(*args, &block) ⇒ Object
sets after_fork hook to a given block.
-
#before_exec(*args, &block) ⇒ Object
sets the before_exec hook to a given Proc object.
-
#before_fork(*args, &block) ⇒ Object
sets before_fork got be a given Proc object.
-
#commit!(server, options = {}) ⇒ Object
:nodoc:.
-
#expand_addr(address) ⇒ Object
expands “unix:path/to/foo” to a socket relative to the current path expands pathnames of sockets if relative to “~” or “~username” expands “*:port and ”:port“ to ”0.0.0.0:port“.
-
#initialize(defaults = {}) ⇒ Configurator
constructor
:nodoc:.
-
#listen(address, opt = {}) ⇒ Object
adds an
address
to the existing listener set. -
#listeners(addresses) ⇒ Object
sets listeners to the given
addresses
, replacing or augmenting the current set. -
#logger(new) ⇒ Object
sets object to the
new
Logger-like object. -
#pid(path) ⇒ Object
sets the
path
for the PID file of the unicorn master process. -
#preload_app(bool) ⇒ Object
Enabling this preloads an application before forking worker processes.
-
#reload ⇒ Object
:nodoc:.
-
#stderr_path(path) ⇒ Object
Allow redirecting $stderr to a given path.
-
#stdout_path(path) ⇒ Object
Same as stderr_path, except for $stdout.
-
#timeout(seconds) ⇒ Object
sets the timeout of worker processes to
seconds
. -
#worker_processes(nr) ⇒ Object
sets the current number of worker_processes to
nr
. -
#working_directory(path) ⇒ Object
sets the working directory for Unicorn.
Constructor Details
#initialize(defaults = {}) ⇒ Configurator
:nodoc:
83 84 85 86 87 88 89 90 91 92 93 |
# File 'lib/unicorn/configurator.rb', line 83 def initialize(defaults = {}) #:nodoc: self.set = Hash.new(:unset) use_defaults = defaults.delete(:use_defaults) self.config_file = defaults.delete(:config_file) set.merge!(DEFAULTS) if use_defaults defaults.each { |key, value| self.send(key, value) } Hash === set[:listener_opts] or set[:listener_opts] = Hash.new { |hash,key| hash[key] = {} } Array === set[:listeners] or set[:listeners] = [] reload end |
Instance Attribute Details
#config_file ⇒ Object
Returns the value of attribute config_file
63 64 65 |
# File 'lib/unicorn/configurator.rb', line 63 def config_file @config_file end |
#set ⇒ Object
Returns the value of attribute set
63 64 65 |
# File 'lib/unicorn/configurator.rb', line 63 def set @set end |
Instance Method Details
#[](key) ⇒ Object
:nodoc:
108 109 110 |
# File 'lib/unicorn/configurator.rb', line 108 def [](key) # :nodoc: set[key] end |
#after_fork(*args, &block) ⇒ Object
sets after_fork hook to a given block. This block will be called by the worker after forking. The following is an example hook which adds a per-process listener to every worker:
after_fork do |server,worker|
# per-process listener ports for debugging/admin:
addr = "127.0.0.1:#{9293 + worker.nr}"
# the negative :tries parameter indicates we will retry forever
# waiting on the existing process to exit with a 5 second :delay
# Existing options for Unicorn::Configurator#listen such as
# :backlog, :rcvbuf, :sndbuf are available here as well.
server.listen(addr, :tries => -1, :delay => 5, :backlog => 128)
# drop permissions to "www-data" in the worker
# generally there's no reason to start Unicorn as a priviledged user
# as it is not recommended to expose Unicorn to public clients.
uid, gid = Process.euid, Process.egid
user, group = 'www-data', 'www-data'
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
end
152 153 154 |
# File 'lib/unicorn/configurator.rb', line 152 def after_fork(*args, &block) set_hook(:after_fork, block_given? ? block : args[0]) end |
#before_exec(*args, &block) ⇒ Object
sets the before_exec hook to a given Proc object. This Proc object will be called by the master process right before exec()-ing the new unicorn binary. This is useful for freeing certain OS resources that you do NOT wish to share with the reexeced child process. There is no corresponding after_exec hook (for obvious reasons).
169 170 171 |
# File 'lib/unicorn/configurator.rb', line 169 def before_exec(*args, &block) set_hook(:before_exec, block_given? ? block : args[0], 1) end |
#before_fork(*args, &block) ⇒ Object
sets before_fork got be a given Proc object. This Proc object will be called by the master process before forking each worker.
159 160 161 |
# File 'lib/unicorn/configurator.rb', line 159 def before_fork(*args, &block) set_hook(:before_fork, block_given? ? block : args[0]) end |
#commit!(server, options = {}) ⇒ Object
:nodoc:
99 100 101 102 103 104 105 106 |
# File 'lib/unicorn/configurator.rb', line 99 def commit!(server, = {}) #:nodoc: skip = [:skip] || [] set.each do |key, value| value == :unset and next skip.include?(key) and next server.__send__("#{key}=", value) end end |
#expand_addr(address) ⇒ Object
expands “unix:path/to/foo” to a socket relative to the current path expands pathnames of sockets if relative to “~” or “~username” expands “*:port and ”:port“ to ”0.0.0.0:port“
362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 |
# File 'lib/unicorn/configurator.rb', line 362 def (address) #:nodoc return "0.0.0.0:#{address}" if Integer === address return address unless String === address case address when %r{\Aunix:(.*)\z} File.($1) when %r{\A~} File.(address) when %r{\A(?:\*:)?(\d+)\z} "0.0.0.0:#$1" when %r{\A(.*):(\d+)\z} # canonicalize the name packed = Socket.pack_sockaddr_in($2.to_i, $1) Socket.unpack_sockaddr_in(packed).reverse!.join(':') else address end end |
#listen(address, opt = {}) ⇒ Object
adds an address
to the existing listener set.
The following options may be specified (but are generally not needed):
:backlog
: this is the backlog of the listen() syscall.
Some operating systems allow negative values here to specify the maximum allowable value. In most cases, this number is only recommendation and there are other OS-specific tunables and variables that can affect this number. See the listen(2) syscall documentation of your OS for the exact semantics of this.
If you are running unicorn on multiple machines, lowering this number can help your load balancer detect when a machine is overloaded and give requests to a different machine.
Default: 1024
:rcvbuf
, :sndbuf
: maximum receive and send buffer sizes of sockets
These correspond to the SO_RCVBUF and SO_SNDBUF settings which can be set via the setsockopt(2) syscall. Some kernels (e.g. Linux 2.4+) have intelligent auto-tuning mechanisms and there is no need (and it is sometimes detrimental) to specify them.
See the socket API documentation of your operating system to determine the exact semantics of these settings and other operating system-specific knobs where they can be specified.
Defaults: operating system defaults
:tcp_nodelay
: disables Nagle’s algorithm on TCP sockets
This has no effect on UNIX sockets.
Default: operating system defaults (usually Nagle’s algorithm enabled)
:tcp_nopush
: enables TCP_CORK in Linux or TCP_NOPUSH in FreeBSD
This will prevent partial TCP frames from being sent out. Enabling tcp_nopush
is generally not needed or recommended as controlling tcp_nodelay
already provides sufficient latency reduction whereas Unicorn does not know when the best times are for flushing corked sockets.
This has no effect on UNIX sockets.
:tries
: times to retry binding a socket if it is already in use
A negative number indicates we will retry indefinitely, this is useful for migrations and upgrades when individual workers are binding to different ports.
Default: 5
:delay
: seconds to wait between successive tries
Default: 0.5 seconds
286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 |
# File 'lib/unicorn/configurator.rb', line 286 def listen(address, opt = {}) address = (address) if String === address [ :backlog, :sndbuf, :rcvbuf, :tries ].each do |key| value = opt[key] or next Integer === value or raise ArgumentError, "not an integer: #{key}=#{value.inspect}" end [ :tcp_nodelay, :tcp_nopush ].each do |key| (value = opt[key]).nil? and next TrueClass === value || FalseClass === value or raise ArgumentError, "not boolean: #{key}=#{value.inspect}" end unless (value = opt[:delay]).nil? Numeric === value or raise ArgumentError, "not numeric: delay=#{value.inspect}" end set[:listener_opts][address].merge!(opt) end set[:listeners] << address end |
#listeners(addresses) ⇒ Object
sets listeners to the given addresses
, replacing or augmenting the current set. This is for the global listener pool shared by all worker processes. For per-worker listeners, see the after_fork example This is for internal API use only, do not use it in your Unicorn config file. Use listen instead.
220 221 222 223 224 |
# File 'lib/unicorn/configurator.rb', line 220 def listeners(addresses) # :nodoc: Array === addresses or addresses = Array(addresses) addresses.map! { |addr| (addr) } set[:listeners] = addresses end |
#logger(new) ⇒ Object
sets object to the new
Logger-like object. The new logger-like object must respond to the following methods:
+debug+, +info+, +warn+, +error+, +fatal+, +close+
115 116 117 118 119 120 121 122 |
# File 'lib/unicorn/configurator.rb', line 115 def logger(new) %w(debug info warn error fatal close).each do |m| new.respond_to?(m) and next raise ArgumentError, "logger=#{new} does not respond to method=#{m}" end set[:logger] = new end |
#pid(path) ⇒ Object
sets the path
for the PID file of the unicorn master process
310 |
# File 'lib/unicorn/configurator.rb', line 310 def pid(path); set_path(:pid, path); end |
#preload_app(bool) ⇒ Object
Enabling this preloads an application before forking worker processes. This allows memory savings when using a copy-on-write-friendly GC but can cause bad things to happen when resources like sockets are opened at load time by the master process and shared by multiple children. People enabling this are highly encouraged to look at the before_fork/after_fork hooks to properly close/reopen sockets. Files opened for logging do not have to be reopened as (unbuffered-in-userspace) files opened with the File::APPEND flag are written to atomically on UNIX.
In addition to reloading the unicorn-specific config settings, SIGHUP will reload application code in the working directory/symlink when workers are gracefully restarted.
325 326 327 328 329 330 331 332 |
# File 'lib/unicorn/configurator.rb', line 325 def preload_app(bool) case bool when TrueClass, FalseClass set[:preload_app] = bool else raise ArgumentError, "preload_app=#{bool.inspect} not a boolean" end end |
#reload ⇒ Object
:nodoc:
95 96 97 |
# File 'lib/unicorn/configurator.rb', line 95 def reload #:nodoc: instance_eval(File.read(config_file), config_file) if config_file end |
#stderr_path(path) ⇒ Object
Allow redirecting $stderr to a given path. Unlike doing this from the shell, this allows the unicorn process to know the path its writing to and rotate the file if it is used for logging. The file will be opened with the File::APPEND flag and writes synchronized to the kernel (but not necessarily to disk) so multiple processes can safely append to it.
340 341 342 |
# File 'lib/unicorn/configurator.rb', line 340 def stderr_path(path) set_path(:stderr_path, path) end |
#stdout_path(path) ⇒ Object
Same as stderr_path, except for $stdout
345 346 347 |
# File 'lib/unicorn/configurator.rb', line 345 def stdout_path(path) set_path(:stdout_path, path) end |
#timeout(seconds) ⇒ Object
sets the timeout of worker processes to seconds
. Workers handling the request/app.call/response cycle taking longer than this time period will be forcibly killed (via SIGKILL). This timeout is enforced by the master process itself and not subject to the scheduling limitations by the worker process. Due the low-complexity, low-overhead implementation, timeouts of less than 3.0 seconds can be considered inaccurate and unsafe.
For running Unicorn behind nginx, it is recommended to set “fail_timeout=0” for in your nginx configuration like this to have nginx always retry backends that may have had workers SIGKILL-ed due to timeouts.
# See http://wiki.nginx.org/NginxHttpUpstreamModule for more details
# on nginx upstream configuration:
upstream unicorn_backend {
# for UNIX domain socket setups:
server unix:/path/to/unicorn.sock fail_timeout=0;
# for TCP setups
server 192.168.0.7:8080 fail_timeout=0;
server 192.168.0.8:8080 fail_timeout=0;
server 192.168.0.9:8080 fail_timeout=0;
}
197 198 199 200 201 202 203 |
# File 'lib/unicorn/configurator.rb', line 197 def timeout(seconds) Numeric === seconds or raise ArgumentError, "not numeric: timeout=#{seconds.inspect}" seconds >= 3 or raise ArgumentError, "too low: timeout=#{seconds.inspect}" set[:timeout] = seconds end |
#worker_processes(nr) ⇒ Object
sets the current number of worker_processes to nr
. Each worker process will serve exactly one client at a time.
207 208 209 210 211 212 213 |
# File 'lib/unicorn/configurator.rb', line 207 def worker_processes(nr) Integer === nr or raise ArgumentError, "not an integer: worker_processes=#{nr.inspect}" nr >= 0 or raise ArgumentError, "not non-negative: worker_processes=#{nr.inspect}" set[:worker_processes] = nr end |
#working_directory(path) ⇒ Object
sets the working directory for Unicorn. This ensures USR2 will start a new instance of Unicorn in this directory. This may be a symlink. You should specify this directive near the top or your config file before any relative paths for other config directives (or avoid relative paths entirely).
354 355 356 357 |
# File 'lib/unicorn/configurator.rb', line 354 def working_directory(path) # just let chdir raise errors Dir.chdir(HttpServer::START_CTX[:cwd] = path) end |