Class: Puma::DSL

Inherits:
Object
  • Object
show all
Defined in:
lib/puma/dsl.rb

Overview

The methods that are available for use inside the configuration file. These same methods are used in Puma cli and the rack handler internally.

Used manually (via CLI class):

config = Configuration.new({}) do |user_config|
  user_config.port 3001
end
config.load

puts config.options[:binds] # => "tcp://127.0.0.1:3001"

Used to load file:

$ cat puma_config.rb
port 3002

Resulting configuration:

config = Configuration.new(config_file: "puma_config.rb")
config.load

puts config.options[:binds] # => "tcp://127.0.0.1:3002"

You can also find many examples being used by the test suite in test/config.

Puma v6 adds the option to specify a key name (String or Symbol) to the hooks that run inside the forked workers. All the hooks run inside the Cluster::Worker#run method.

Previously, the worker index and the LogWriter instance were passed to the hook blocks/procs. If a key name is specified, a hash is passed as the last parameter. This allows storage of data, typically objects that are created before the worker that need to be passed to the hook when the worker is shutdown.

The following hooks have been updated:

| DSL Method         |  Options Key            | Fork Block Location |
| on_worker_boot     | :before_worker_boot     | inside, before      |
| on_worker_shutdown | :before_worker_shutdown | inside, after       |
| on_refork          | :before_refork          | inside              |

Constant Summary collapse

ON_WORKER_KEY = 
[String, Symbol].freeze

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options, config) ⇒ DSL

Returns a new instance of DSL.



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# File 'lib/puma/dsl.rb', line 125

def initialize(options, config)
  @config  = config
  @options = options

  @plugins = []
end

Class Method Details

.ssl_bind_str(host, port, opts) ⇒ Object

Convenience method so logic can be used in CI.

See Also:



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# File 'lib/puma/dsl.rb', line 58

def self.ssl_bind_str(host, port, opts)
  verify = opts.fetch(:verify_mode, 'none').to_s

  tls_str =
    if opts[:no_tlsv1_1]  then '&no_tlsv1_1=true'
    elsif opts[:no_tlsv1] then '&no_tlsv1=true'
    else ''
    end

  ca_additions = "&ca=#{Puma::Util.escape(opts[:ca])}" if ['peer', 'force_peer'].include?(verify)

  low_latency_str = opts.key?(:low_latency) ? "&low_latency=#{opts[:low_latency]}" : ''
  backlog_str = opts[:backlog] ? "&backlog=#{Integer(opts[:backlog])}" : ''

  if defined?(JRUBY_VERSION)
    cipher_suites = opts[:ssl_cipher_list] ? "&ssl_cipher_list=#{opts[:ssl_cipher_list]}" : nil # old name
    cipher_suites = "#{cipher_suites}&cipher_suites=#{opts[:cipher_suites]}" if opts[:cipher_suites]
    protocols = opts[:protocols] ? "&protocols=#{opts[:protocols]}" : nil

    keystore_additions = "keystore=#{opts[:keystore]}&keystore-pass=#{opts[:keystore_pass]}"
    keystore_additions = "#{keystore_additions}&keystore-type=#{opts[:keystore_type]}" if opts[:keystore_type]
    if opts[:truststore]
      truststore_additions = "&truststore=#{opts[:truststore]}"
      truststore_additions = "#{truststore_additions}&truststore-pass=#{opts[:truststore_pass]}" if opts[:truststore_pass]
      truststore_additions = "#{truststore_additions}&truststore-type=#{opts[:truststore_type]}" if opts[:truststore_type]
    end

    "ssl://#{host}:#{port}?#{keystore_additions}#{truststore_additions}#{cipher_suites}#{protocols}" \
      "&verify_mode=#{verify}#{tls_str}#{ca_additions}#{backlog_str}"
  else
    ssl_cipher_filter = opts[:ssl_cipher_filter] ? "&ssl_cipher_filter=#{opts[:ssl_cipher_filter]}" : nil
    ssl_ciphersuites = opts[:ssl_ciphersuites] ? "&ssl_ciphersuites=#{opts[:ssl_ciphersuites]}" : nil
    v_flags = (ary = opts[:verification_flags]) ? "&verification_flags=#{Array(ary).join ','}" : nil

    cert_flags = (cert = opts[:cert]) ? "cert=#{Puma::Util.escape(cert)}" : nil
    key_flags = (key = opts[:key]) ? "&key=#{Puma::Util.escape(key)}" : nil
    password_flags = (password_command = opts[:key_password_command]) ? "&key_password_command=#{Puma::Util.escape(password_command)}" : nil

    reuse_flag =
      if (reuse = opts[:reuse])
        if reuse == true
          '&reuse=dflt'
        elsif reuse.is_a?(Hash) && (reuse.key?(:size) || reuse.key?(:timeout))
          val = +''
          if (size = reuse[:size]) && Integer === size
            val << size.to_s
          end
          if (timeout = reuse[:timeout]) && Integer === timeout
            val << ",#{timeout}"
          end
          if val.empty?
            nil
          else
            "&reuse=#{val}"
          end
        else
          nil
        end
      else
        nil
      end

    "ssl://#{host}:#{port}?#{cert_flags}#{key_flags}#{password_flags}#{ssl_cipher_filter}#{ssl_ciphersuites}" \
      "#{reuse_flag}&verify_mode=#{verify}#{tls_str}#{ca_additions}#{v_flags}#{backlog_str}#{low_latency_str}"
  end
end

Instance Method Details

#_load_from(path) ⇒ Object 



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# File 'lib/puma/dsl.rb', line 132

def _load_from(path)
  if path
    @path = path
    instance_eval(File.read(path), path, 1)
  end
ensure
  _offer_plugins
end

#_offer_plugins ⇒ Object 



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# File 'lib/puma/dsl.rb', line 141

def _offer_plugins
  @plugins.each do |o|
    if o.respond_to? :config
      @options.shift
      o.config self
    end
  end

  @plugins.clear
end

#activate_control_app(url = "auto", opts = {}) ⇒ Object

Start the Puma control rack application on url. This application can be communicated with to control the main server. Additionally, you can provide an authentication token, so all requests to the control server will need to include that token as a query parameter. This allows for simple authentication.

Check out App::Status to see what the app has available.

Examples:

activate_control_app 'unix:///var/run/pumactl.sock'
activate_control_app 'unix:///var/run/pumactl.sock', { auth_token: '12345' }
activate_control_app 'unix:///var/run/pumactl.sock', { no_token: true }


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# File 'lib/puma/dsl.rb', line 219

def activate_control_app(url="auto", opts={})
  if url == "auto"
    path = Configuration.temp_path
    @options[:control_url] = "unix://#{path}"
    @options[:control_url_temp] = path
  else
    @options[:control_url] = url
  end

  if opts[:no_token]
    # We need to use 'none' rather than :none because this value will be
    # passed on to an instance of OptionParser, which doesn't support
    # symbols as option values.
    #
    # See: https://github.com/puma/puma/issues/1193#issuecomment-305995488
    auth_token = 'none'
  else
    auth_token = opts[:auth_token]
    auth_token ||= Configuration.random_token
  end

  @options[:control_auth_token] = auth_token
  @options[:control_url_umask] = opts[:umask] if opts[:umask]
end

#after_worker_fork(&block) ⇒ Object Also known as: after_worker_boot

Note:

Cluster mode only.

Code to run in the master after a worker has been started. The worker’s index is passed as an argument.

This is called everytime a worker is to be started.

Examples:

after_worker_fork do
  puts 'After worker fork...'
end


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# File 'lib/puma/dsl.rb', line 807

def after_worker_fork(&block)
  warn_if_in_single_mode('after_worker_fork')

  process_hook :after_worker_fork, nil, block, 'after_worker_fork'
end

#app(obj = nil, &block) ⇒ Object

Use an object or block as the rack application. This allows the configuration file to be the application itself.

Examples:

app do |env|
  body = 'Hello, World!'

  [
    200,
    {
      'Content-Type' => 'text/plain',
      'Content-Length' => body.length.to_s
    },
    [body]
  ]
end

See Also:



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# File 'lib/puma/dsl.rb', line 196

def app(obj=nil, &block)
  obj ||= block

  raise "Provide either a #call'able or a block" unless obj

  @options[:app] = obj
end

#before_fork(&block) ⇒ Object

Note:

Cluster mode only.

Code to run immediately before master process forks workers (once on boot). These hooks can block if necessary to wait for background operations unknown to Puma to finish before the process terminates. This can be used to close any connections to remote servers (database, Redis, …) that were opened when preloading the code.

This can be called multiple times to add several hooks.

Examples:

before_fork do
  puts "Starting workers..."
end


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# File 'lib/puma/dsl.rb', line 731

def before_fork(&block)
  warn_if_in_single_mode('before_fork')

  @options[:before_fork] ||= []
  @options[:before_fork] << block
end

#bind(url) ⇒ Object

Bind the server to url. “tcp://”, “unix://” and “ssl://” are the only accepted protocols. Multiple urls can be bound to, calling bind does not overwrite previous bindings.

The default is “tcp://0.0.0.0:9292”.

You can use query parameters within the url to specify options:

  • Set the socket backlog depth with backlog, default is 1024.

  • Set up an SSL certificate with key & cert.

  • Set up an SSL certificate for mTLS with key, cert, ca and verify_mode.

  • Set whether to optimize for low latency instead of throughput with low_latency, default is to not optimize for low latency. This is done via Socket::TCP_NODELAY.

  • Set socket permissions with umask.

Examples:

Backlog depth

bind 'unix:///var/run/puma.sock?backlog=512'

SSL cert

bind 'ssl://127.0.0.1:9292?key=key.key&cert=cert.pem'

SSL cert for mutual TLS (mTLS)

bind 'ssl://127.0.0.1:9292?key=key.key&cert=cert.pem&ca=ca.pem&verify_mode=force_peer'

Disable optimization for low latency

bind 'tcp://0.0.0.0:9292?low_latency=false'

Socket permissions

bind 'unix:///var/run/puma.sock?umask=0111'

See Also:



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# File 'lib/puma/dsl.rb', line 285

def bind(url)
  @options[:binds] ||= []
  @options[:binds] << url
end

#bind_to_activated_sockets(bind = true) ⇒ Object

Bind to (systemd) activated sockets, regardless of configured binds.

Systemd can present sockets as file descriptors that are already opened. By default Puma will use these but only if it was explicitly told to bind to the socket. If not, it will close the activated sockets. This means all configuration is duplicated.

Binds can contain additional configuration, but only SSL config is really relevant since the unix and TCP socket options are ignored.

This means there is a lot of duplicated configuration for no additional value in most setups. This method tells the launcher to bind to all activated sockets, regardless of existing bind.

To clear configured binds, the value only can be passed. This will clear out any binds that may have been configured.

Examples:

Use any systemd activated sockets as well as configured binds

bind_to_activated_sockets

Only bind to systemd activated sockets, ignoring other binds

bind_to_activated_sockets 'only'


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# File 'lib/puma/dsl.rb', line 317

def bind_to_activated_sockets(bind=true)
  @options[:bind_to_activated_sockets] = bind
end

#clean_thread_locals(which = true) ⇒ Object

Work around leaky apps that leave garbage in Thread locals across requests.

The default is false.

Examples:

clean_thread_locals


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# File 'lib/puma/dsl.rb', line 380

def clean_thread_locals(which=true)
  @options[:clean_thread_locals] = which
end

#clear_binds! ⇒ Object 



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# File 'lib/puma/dsl.rb', line 290

def clear_binds!
  @options[:binds] = []
end

#custom_logger(custom_logger) ⇒ Object

Pass in a custom logging class instance

Examples:

custom_logger Logger.new('t.log')


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# File 'lib/puma/dsl.rb', line 492

def custom_logger(custom_logger)
  @options[:custom_logger] = custom_logger
end

#debug ⇒ Object

Show debugging info

The default is false.

Examples:

debug


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# File 'lib/puma/dsl.rb', line 503

def debug
  @options[:debug] = true
end

#default_host ⇒ Object 



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# File 'lib/puma/dsl.rb', line 156

def default_host
  @options[:default_host] || Configuration::DEFAULTS[:tcp_host]
end

#directory(dir) ⇒ Object

The directory to operate out of.

The default is the current directory.

Examples:

directory '/u/apps/lolcat'


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# File 'lib/puma/dsl.rb', line 929

def directory(dir)
  @options[:directory] = dir.to_s
end

#drain_on_shutdown(which = true) ⇒ Object

When shutting down, drain the accept socket of pending connections and process them. This loops over the accept socket until there are no more read events and then stops looking and waits for the requests to finish.

See Also:



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# File 'lib/puma/dsl.rb', line 390

def drain_on_shutdown(which=true)
  @options[:drain_on_shutdown] = which
end

#early_hints(answer = true) ⇒ Object

Enable HTTP 103 Early Hints responses.

The default is nil.

Examples:

early_hints


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# File 'lib/puma/dsl.rb', line 533

def early_hints(answer=true)
  @options[:early_hints] = answer
end

#enable_keep_alives(enabled = true) ⇒ Object

When ‘true`, keep-alive connections are maintained on inbound requests. Enabling this setting reduces the number of TCP operations, reducing response times for connections that can send multiple requests in a single connection.

When Puma receives more incoming connections than available Puma threads, enabling the keep-alive behavior may result in processing requests out-of-order, increasing overall response time variance. Increased response time variance means that the overall average of response times might not change, but more outliers will exist. Those long-tail outliers may significantly affect response times for some processed requests.

When ‘false`, Puma closes the connection after each request, requiring the client to open a new request. Disabling this setting guarantees that requests will be processed in the order they are fully received, decreasing response variance and eliminating long-tail outliers caused by keep-alive behavior. The trade-off is that the number of TCP operations required will increase.

The default is true.

Examples:

enable_keep_alives false


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# File 'lib/puma/dsl.rb', line 1294

def enable_keep_alives(enabled=true)
  @options[:enable_keep_alives] = enabled
end

#environment(environment) ⇒ Object

Set the environment in which the rack’s app will run. The value must be a string.

The default is “development”.

Examples:

environment 'production'


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# File 'lib/puma/dsl.rb', line 402

def environment(environment)
  @options[:environment] = environment
end

#extra_runtime_dependencies(answer = []) ⇒ Object

When using prune_bundler, if extra runtime dependencies need to be loaded to initialize your app, then this setting can be used. This includes any Puma plugins.

Before bundler is pruned, the gem names supplied will be looked up in the bundler context and then loaded again after bundler is pruned. Only applies if prune_bundler is used.

Examples:

extra_runtime_dependencies ['gem_name_1', 'gem_name_2']
extra_runtime_dependencies ['puma_worker_killer', 'puma-heroku']

See Also:

  • Launcher#extra_runtime_deps_directories


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# File 'lib/puma/dsl.rb', line 1015

def extra_runtime_dependencies(answer = [])
  @options[:extra_runtime_dependencies] = Array(answer)
end

#first_data_timeout(seconds) ⇒ Object

Define how long the tcp socket stays open, if no data has been received.

The default is 30 seconds.

Examples:

first_data_timeout 40

See Also:

  • Server.new


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# File 'lib/puma/dsl.rb', line 342

def first_data_timeout(seconds)
  @options[:first_data_timeout] = Integer(seconds)
end

#force_shutdown_after(val = :forever) ⇒ Object

How long to wait for threads to stop when shutting them down. Specifying :immediately will cause Puma to kill the threads immediately. Otherwise the value is the number of seconds to wait.

Puma always waits a few seconds after killing a thread for it to try to finish up it’s work, even in :immediately mode.

The default is :forever.

See Also:



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# File 'lib/puma/dsl.rb', line 417

def force_shutdown_after(val=:forever)
  i = case val
      when :forever
        -1
      when :immediately
        0
      else
        Float(val)
      end

  @options[:force_shutdown_after] = i
end

#fork_worker(after_requests = 1000) ⇒ Object

Note:

Cluster mode only.

When enabled, workers will be forked from worker 0 instead of from the master process. This option is similar to ‘preload_app` because the app is preloaded before forking, but it is compatible with phased restart.

This option also enables the ‘refork` command (SIGURG), which optimizes copy-on-write performance in a running app.

A refork will automatically trigger once after the specified number of requests (default 1000), or pass 0 to disable auto refork.

Version:

  • 5.0.0



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# File 'lib/puma/dsl.rb', line 1256

def fork_worker(after_requests=1000)
  @options[:fork_worker] = Integer(after_requests)
end

#get(key, default = nil) ⇒ Object 



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# File 'lib/puma/dsl.rb', line 164

def get(key,default=nil)
  @options[key.to_sym] || default
end

#http_content_length_limit(limit) ⇒ Object

Specify how big the request payload should be, in bytes. This limit is compared against Content-Length HTTP header. If the payload size (CONTENT_LENGTH) is larger than http_content_length_limit, HTTP 413 status code is returned.

When no Content-Length http header is present, it is compared against the size of the body of the request.

The default is nil.

Examples:

http_content_length_limit 2_000_000_000


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# File 'lib/puma/dsl.rb', line 1342

def http_content_length_limit(limit)
  @options[:http_content_length_limit] = limit
end

#idle_timeout(seconds) ⇒ Object

If a new request is not received within this number of seconds, begin shutting down.

The default is nil.

Examples:

idle_timeout 60

See Also:

  • Server.new


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# File 'lib/puma/dsl.rb', line 368

def idle_timeout(seconds)
  @options[:idle_timeout] = Integer(seconds)
end

#inject(&blk) ⇒ Object 



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# File 'lib/puma/dsl.rb', line 160

def inject(&blk)
  instance_eval(&blk)
end

#io_selector_backend(backend) ⇒ Object

Specify the backend for the IO selector.

Provided values will be passed directly to NIO::Selector.new, with the exception of :auto which will let nio4r choose the backend.

Check the documentation of NIO::Selector.backends for the list of valid options. Note that the available options on your system will depend on the operating system. If you want to use the pure Ruby backend (not recommended due to its comparatively low performance), set environment variable NIO4R_PURE to true.

The default is :auto.

See Also:



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# File 'lib/puma/dsl.rb', line 1313

def io_selector_backend(backend)
  @options[:io_selector_backend] = backend.to_sym
end

#load(file) ⇒ Object

Load additional configuration from a file. Files get loaded later via Configuration#load.

Examples:

load 'config/puma/production.rb'


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# File 'lib/puma/dsl.rb', line 250

def load(file)
  @options[:config_files] ||= []
  @options[:config_files] << file
end

#log_formatter(&block) ⇒ Object 



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# File 'lib/puma/dsl.rb', line 553

def log_formatter(&block)
  @options[:log_formatter] = block
end

#log_requests(which = true) ⇒ Object

Enable request logging, the inverse of ‘quiet`.

The default is false.

Examples:

log_requests


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# File 'lib/puma/dsl.rb', line 483

def log_requests(which=true)
  @options[:log_requests] = which
end

#lowlevel_error_handler(obj = nil, &block) ⇒ Object

Use obj or block as the low level error handler. This allows the configuration file to change the default error on the server.

Examples:

lowlevel_error_handler do |err|
  [200, {}, ["error page"]]
end


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# File 'lib/puma/dsl.rb', line 955

def lowlevel_error_handler(obj=nil, &block)
  obj ||= block
  raise "Provide either a #call'able or a block" unless obj
  @options[:lowlevel_error_handler] = obj
end

#max_fast_inline(num_of_requests) ⇒ Object

The number of requests to attempt inline before sending a client back to the reactor to be subject to normal ordering.

The default is 10.

Examples:

max_fast_inline 20


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# File 'lib/puma/dsl.rb', line 1268

def max_fast_inline(num_of_requests)
  @options[:max_fast_inline] = Float(num_of_requests)
end

#mutate_stdout_and_stderr_to_sync_on_write(enabled = true) ⇒ Object

Ensures STDOUT and STDERR is immediately flushed to the underlying operating system and is not buffered internally

The default is true.

Examples:

mutate_stdout_and_stderr_to_sync_on_write false


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# File 'lib/puma/dsl.rb', line 1325

def mutate_stdout_and_stderr_to_sync_on_write(enabled=true)
  @options[:mutate_stdout_and_stderr_to_sync_on_write] = enabled
end

#on_booted(&block) ⇒ Object

Code to run after puma is booted (works for both: single and clustered)

Examples:

on_booted do
  puts 'After booting...'
end


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# File 'lib/puma/dsl.rb', line 822

def on_booted(&block)
  @config.options[:events].on_booted(&block)
end

#on_refork(key = nil, &block) ⇒ Object

Note:

Cluster mode with ‘fork_worker` enabled only.

When ‘fork_worker` is enabled, code to run in Worker 0 before all other workers are re-forked from this process, after the server has temporarily stopped serving requests (once per complete refork cycle).

This can be used to trigger extra garbage-collection to maximize copy-on-write efficiency, or close any connections to remote servers (database, Redis, …) that were opened while the server was running.

This can be called multiple times to add several hooks.

Examples:

on_refork do
  3.times {GC.start}
end

Version:

  • 5.0.0



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# File 'lib/puma/dsl.rb', line 857

def on_refork(key = nil, &block)
  process_hook :before_refork, key, block, 'on_refork'
end

#on_restart(&block) ⇒ Object

Code to run before doing a restart. This code should close log files, database connections, etc.

This can be called multiple times to add code each time.

Examples:

on_restart do
  puts 'On restart...'
end


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# File 'lib/puma/dsl.rb', line 440

def on_restart(&block)
  @options[:on_restart] ||= []
  @options[:on_restart] << block
end

#on_stopped(&block) ⇒ Object

Code to run after puma is stopped (works for both: single and clustered)

Examples:

on_stopped do
  puts 'After stopping...'
end


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# File 'lib/puma/dsl.rb', line 833

def on_stopped(&block)
  @config.options[:events].on_stopped(&block)
end

#on_thread_exit(&block) ⇒ Object

Provide a block to be executed after a thread is trimmed from the thread pool. Be careful: while this block executes, Puma’s main loop is blocked, so no new requests will be picked up.

This hook only runs when a thread in the threadpool is trimmed by Puma. It does not run when a thread dies due to exceptions or any other cause.

Return values are ignored. Raising an exception will log a warning.

This hook is useful for cleaning up thread local resources when a thread is trimmed.

This can be called multiple times to add several hooks.

Examples:

on_thread_exit do
  puts 'On thread exit...'
end


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# File 'lib/puma/dsl.rb', line 903

def on_thread_exit(&block)
  @options[:before_thread_exit] ||= []
  @options[:before_thread_exit] << block
end

#on_thread_start(&block) ⇒ Object

Provide a block to be executed just before a thread is added to the thread pool. Be careful: while the block executes, thread creation is delayed, and probably a request will have to wait too! The new thread will not be added to the threadpool until the provided block returns.

Return values are ignored. Raising an exception will log a warning.

This hook is useful for doing something when the thread pool grows.

This can be called multiple times to add several hooks.

Examples:

on_thread_start do
  puts 'On thread start...'
end


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# File 'lib/puma/dsl.rb', line 878

def on_thread_start(&block)
  @options[:before_thread_start] ||= []
  @options[:before_thread_start] << block
end

#on_worker_boot(key = nil, &block) ⇒ Object

Note:

Cluster mode only.

Code to run in a worker when it boots to setup the process before booting the app.

This can be called multiple times to add several hooks.

Examples:

on_worker_boot do
  puts 'Before worker boot...'
end


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# File 'lib/puma/dsl.rb', line 750

def on_worker_boot(key = nil, &block)
  warn_if_in_single_mode('on_worker_boot')

  process_hook :before_worker_boot, key, block, 'on_worker_boot'
end

#on_worker_fork(&block) ⇒ Object

Note:

Cluster mode only.

Code to run in the master right before a worker is started. The worker’s index is passed as an argument.

This can be called multiple times to add several hooks.

Examples:

on_worker_fork do
  puts 'Before worker fork...'
end


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# File 'lib/puma/dsl.rb', line 789

def on_worker_fork(&block)
  warn_if_in_single_mode('on_worker_fork')

  process_hook :before_worker_fork, nil, block, 'on_worker_fork'
end

#on_worker_shutdown(key = nil, &block) ⇒ Object

Note:

Cluster mode only.

Code to run immediately before a worker shuts down (after it has finished processing HTTP requests). The worker’s index is passed as an argument. These hooks can block if necessary to wait for background operations unknown to Puma to finish before the process terminates.

This can be called multiple times to add several hooks.

Examples:

on_worker_shutdown do
  puts 'On worker shutdown...'
end


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# File 'lib/puma/dsl.rb', line 771

def on_worker_shutdown(key = nil, &block)
  warn_if_in_single_mode('on_worker_shutdown')

  process_hook :before_worker_shutdown, key, block, 'on_worker_shutdown'
end

#out_of_band(&block) ⇒ Object

Code to run out-of-band when the worker is idle. These hooks run immediately after a request has finished processing and there are no busy threads on the worker. The worker doesn’t accept new requests until this code finishes.

This hook is useful for running out-of-band garbage collection or scheduling asynchronous tasks to execute after a response.

This can be called multiple times to add several hooks.



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# File 'lib/puma/dsl.rb', line 918

def out_of_band(&block)
  process_hook :out_of_band, nil, block, 'out_of_band'
end

#persistent_timeout(seconds) ⇒ Object

Define how long persistent connections can be idle before Puma closes them.

The default is 20 seconds.

Examples:

persistent_timeout 30

See Also:

  • Server.new


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# File 'lib/puma/dsl.rb', line 355

def persistent_timeout(seconds)
  @options[:persistent_timeout] = Integer(seconds)
end

#pidfile(path) ⇒ Object

Store the pid of the server in the file at “path”.

Examples:

pidfile '/u/apps/lolcat/tmp/pids/puma.pid'


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# File 'lib/puma/dsl.rb', line 461

def pidfile(path)
  @options[:pidfile] = path.to_s
end

#plugin(name) ⇒ Object

Load the named plugin for use by this configuration.

Examples:

plugin :tmp_restart


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# File 'lib/puma/dsl.rb', line 173

def plugin(name)
  @plugins << @config.load_plugin(name)
end

#port(port, host = nil) ⇒ Object

Define the TCP port to bind to. Use ‘bind` for more advanced options.

The default is 9292.

Examples:

port 3000


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# File 'lib/puma/dsl.rb', line 328

def port(port, host=nil)
  host ||= default_host
  bind URI::Generic.build(scheme: 'tcp', host: host, port: Integer(port)).to_s
end

#preload_app!(answer = true) ⇒ Object

Note:

Cluster mode only.

Preload the application before starting the workers; this conflicts with phased restart feature.

The default is true if your app uses more than 1 worker.

Examples:

preload_app!


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# File 'lib/puma/dsl.rb', line 943

def preload_app!(answer=true)
  @options[:preload_app] = answer
end

#prune_bundler(answer = true) ⇒ Object

Note:

This is incompatible with preload_app!.

Note:

This is only supported for RubyGems 2.2+

This option is used to allow your app and its gems to be properly reloaded when not using preload.

When set, if Puma detects that it’s been invoked in the context of Bundler, it will cleanup the environment and re-run itself outside the Bundler environment, but directly using the files that Bundler has setup.

This means that Puma is now decoupled from your Bundler context and when each worker loads, it will be loading a new Bundler context and thus can float around as the release dictates.

See Also:



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# File 'lib/puma/dsl.rb', line 979

def prune_bundler(answer=true)
  @options[:prune_bundler] = answer
end

#queue_requests(answer = true) ⇒ Object

When set to true, workers accept all requests and queue them before passing them to the handlers. When set to false, each worker process accepts exactly as many requests as it is configured to simultaneously handle.

Queueing requests generally improves performance. In some cases, such as a single threaded application, it may be better to ensure requests get balanced across workers.

Note that setting this to false disables HTTP keepalive and slow clients will occupy a handler thread while the request is being sent. A reverse proxy, such as nginx, can handle slow clients and queue requests before they reach Puma.

The default is true.

See Also:



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# File 'lib/puma/dsl.rb', line 1153

def queue_requests(answer=true)
  @options[:queue_requests] = answer
end

#quiet(which = true) ⇒ Object

Disable request logging, the inverse of ‘log_requests`.

The default is true.

Examples:

quiet


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# File 'lib/puma/dsl.rb', line 472

def quiet(which=true)
  @options[:log_requests] = !which
end

#rack_url_scheme(scheme = nil) ⇒ Object

Allows setting ‘env`. Only necessary if X-Forwarded-Proto is not being set by your proxy Normal values are ’http’ or ‘https’.



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# File 'lib/puma/dsl.rb', line 522

def rack_url_scheme(scheme=nil)
  @options[:rack_url_scheme] = scheme
end

#rackup(path) ⇒ Object

Load path as a rackup file.

The default is “config.ru”.

Examples:

rackup '/u/apps/lolcat/config.ru'


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# File 'lib/puma/dsl.rb', line 514

def rackup(path)
  @options[:rackup] ||= path.to_s
end

#raise_exception_on_sigterm(answer = true) ⇒ Object

Raises a SignalException when SIGTERM is received. In environments where SIGTERM is something expected, you can suppress these with this option.

This can be useful for example in Kubernetes, where rolling restart is guaranteed usually on the infrastructure level.

The default is true.

Examples:

raise_exception_on_sigterm false

See Also:



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# File 'lib/puma/dsl.rb', line 997

def raise_exception_on_sigterm(answer=true)
  @options[:raise_exception_on_sigterm] = answer
end

#restart_command(cmd) ⇒ Object

Command to use to restart Puma. This should be just how to load Puma itself (ie. ‘ruby -Ilib bin/puma’), not the arguments to Puma, as those are the same as the original process.

Examples:

restart_command '/u/app/lolcat/bin/restart_puma'


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# File 'lib/puma/dsl.rb', line 452

def restart_command(cmd)
  @options[:restart_cmd] = cmd.to_s
end

#set_default_host(host) ⇒ Object 



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# File 'lib/puma/dsl.rb', line 152

def set_default_host(host)
  @options[:default_host] = host
end

#set_remote_address(val = :socket) ⇒ Object

Control how the remote address of the connection is set. This is configurable because to calculate the true socket peer address a kernel syscall is required which for very fast rack handlers slows down the handling significantly.

There are 5 possible values:

  1. :socket - read the peername from the socket using the syscall. This is the normal behavior. If this fails for any reason (e.g., if the peer disconnects between the connection being accepted and the getpeername system call), Puma will return “0.0.0.0”

  2. :localhost - set the remote address to “127.0.0.1”

  3. **header: <http_header>**- set the remote address to the value of the provided http header. For instance: ‘set_remote_address header: “X-Real-IP”`. Only the first word (as separated by spaces or comma) is used, allowing headers such as X-Forwarded-For to be used as well. If this header is absent, Puma will fall back to the behavior of :socket

  4. **proxy_protocol: :v1**- set the remote address to the value read from the HAproxy PROXY protocol, version 1. If the request does not have the PROXY protocol attached to it, will fall back to :socket

  5. **<Any string>** - this allows you to hardcode remote address to any value you wish. Because Puma never uses this field anyway, it’s format is entirely in your hands.

The default is :socket.

Examples:

set_remote_address :localhost


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# File 'lib/puma/dsl.rb', line 1213

def set_remote_address(val=:socket)
  case val
  when :socket
    @options[:remote_address] = val
  when :localhost
    @options[:remote_address] = :value
    @options[:remote_address_value] = "127.0.0.1".freeze
  when String
    @options[:remote_address] = :value
    @options[:remote_address_value] = val
  when Hash
    if hdr = val[:header]
      @options[:remote_address] = :header
      @options[:remote_address_header] = "HTTP_" + hdr.upcase.tr("-", "_")
    elsif protocol_version = val[:proxy_protocol]
      @options[:remote_address] = :proxy_protocol
      protocol_version = protocol_version.downcase.to_sym
      unless [:v1].include?(protocol_version)
        raise "Invalid value for proxy_protocol - #{protocol_version.inspect}"
      end
      @options[:remote_address_proxy_protocol] = protocol_version
    else
      raise "Invalid value for set_remote_address - #{val.inspect}"
    end
  else
    raise "Invalid value for set_remote_address - #{val}"
  end
end

#shutdown_debug(val = true) ⇒ Object

When a shutdown is requested, the backtraces of all the threads will be written to $stdout. This can help figure out why shutdown is hanging.



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# File 'lib/puma/dsl.rb', line 1161

def shutdown_debug(val=true)
  @options[:shutdown_debug] = val
end

#silence_fork_callback_warning ⇒ Object

Disable warning message when running single mode with callback hook defined.

The default is false.

Examples:

silence_fork_callback_warning


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# File 'lib/puma/dsl.rb', line 711

def silence_fork_callback_warning
  @options[:silence_fork_callback_warning] = true
end

#silence_single_worker_warning ⇒ Object

Note:

Cluster mode only.

Disable warning message when running in cluster mode with a single worker.

Cluster mode has some overhead of running an additional ‘control’ process in order to manage the cluster. If only running a single worker it is likely not worth paying that overhead vs running in single mode with additional threads instead.

There are some scenarios where running cluster mode with a single worker may still be warranted and valid under certain deployment scenarios, see github.com/puma/puma/issues/2534

Moving from workers = 1 to workers = 0 will save 10-30% of memory use.

The default is false.

Examples:

silence_single_worker_warning


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# File 'lib/puma/dsl.rb', line 700

def silence_single_worker_warning
  @options[:silence_single_worker_warning] = true
end

#ssl_bind(host, port, opts = {}) ⇒ Object

Instead of using bind and manually constructing a URI like:

bind 'ssl://127.0.0.1:9292?key=key_path&cert=cert_path'

you can use the this method.

When binding on localhost you don’t need to specify cert and key, Puma will assume you are using the localhost gem and try to load the appropriate files.

When using the options hash parameter, the ‘reuse:` value is either `true`, which sets reuse ’on’ with default values, or a hash, with ‘:size` and/or `:timeout` keys, each with integer values.

The ‘cert:` options hash parameter can be the path to a certificate file including all intermediate certificates in PEM format.

The ‘cert_pem:` options hash parameter can be String containing the cerificate and all intermediate certificates in PEM format.

Examples:

ssl_bind '127.0.0.1', '9292', {
  cert: path_to_cert,
  key: path_to_key,
  ssl_cipher_filter: cipher_filter, # optional
  ssl_ciphersuites: ciphersuites,   # optional
  verify_mode: verify_mode,         # default 'none'
  verification_flags: flags,        # optional, not supported by JRuby
  reuse: true                       # optional
}

Using self-signed certificate with the localhost gem:

ssl_bind '127.0.0.1', '9292'

Alternatively, you can provide cert_pem and key_pem:

ssl_bind '127.0.0.1', '9292', {
  cert_pem: File.read(path_to_cert),
  key_pem: File.read(path_to_key),
  reuse: {size: 2_000, timeout: 20} # optional
}

For JRuby, two keys are required: keystore & keystore_pass

ssl_bind '127.0.0.1', '9292', {
  keystore: path_to_keystore,
  keystore_pass: password,
  ssl_cipher_list: cipher_list,     # optional
  verify_mode: verify_mode          # default 'none'
}


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# File 'lib/puma/dsl.rb', line 637

def ssl_bind(host, port, opts = {})
  add_pem_values_to_options_store(opts)
  bind self.class.ssl_bind_str(host, port, opts)
end

#state_path(path) ⇒ Object

Use path as the file to store the server info state. This is used by pumactl to query and control the server.

Examples:

state_path '/u/apps/lolcat/tmp/pids/puma.state'


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# File 'lib/puma/dsl.rb', line 648

def state_path(path)
  @options[:state] = path.to_s
end

#state_permission(permission) ⇒ Object

Use permission to restrict permissions for the state file.

Examples:

state_permission 0600

Version:

  • 5.0.0



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# File 'lib/puma/dsl.rb', line 659

def state_permission(permission)
  @options[:state_permission] = permission
end

#stdout_redirect(stdout = nil, stderr = nil, append = false) ⇒ Object

Redirect STDOUT and STDERR to files specified. The append parameter specifies whether the output is appended.

The default is false.

Examples:

stdout_redirect '/app/lolcat/log/stdout', '/app/lolcat/log/stderr'
stdout_redirect '/app/lolcat/log/stdout', '/app/lolcat/log/stderr', true


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# File 'lib/puma/dsl.rb', line 547

def stdout_redirect(stdout=nil, stderr=nil, append=false)
  @options[:redirect_stdout] = stdout
  @options[:redirect_stderr] = stderr
  @options[:redirect_append] = append
end

#supported_http_methods(methods) ⇒ Object

Note:

If the ‘methods` value is `:any`, no method check with be performed, similar to Puma v5 and earlier.

Supported http methods, which will replace ‘Puma::Const::SUPPORTED_HTTP_METHODS`. The value of `:any` will allows all methods, otherwise, the value must be an array of strings. Note that methods are all uppercase.

‘Puma::Const::SUPPORTED_HTTP_METHODS` is conservative, if you want a complete set of methods, the methods defined by the [IANA Method Registry](www.iana.org/assignments/http-methods/http-methods.xhtml) are pre-defined as the constant `Puma::Const::IANA_HTTP_METHODS`.

Examples:

Adds ‘PROPFIND’ to existing supported methods

supported_http_methods(Puma::Const::SUPPORTED_HTTP_METHODS + ['PROPFIND'])

Restricts methods to the array elements

supported_http_methods %w[HEAD GET POST PUT DELETE OPTIONS PROPFIND]

Restricts methods to the methods in the IANA Registry

supported_http_methods Puma::Const::IANA_HTTP_METHODS

Allows any method

supported_http_methods :any


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# File 'lib/puma/dsl.rb', line 1367

def supported_http_methods(methods)
  if methods == :any
    @options[:supported_http_methods] = :any
  elsif Array === methods && methods == (ary = methods.grep(String).uniq) &&
    !ary.empty?
    @options[:supported_http_methods] = ary
  else
    raise "supported_http_methods must be ':any' or a unique array of strings"
  end
end

#tag(string) ⇒ Object

Additional text to display in process listing.

If you do not specify a tag, Puma will infer it. If you do not want Puma to add a tag, use an empty string.

The default is the current file or directory base name.

Examples:

tag 'app name'
tag ''


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# File 'lib/puma/dsl.rb', line 1031

def tag(string)
  @options[:tag] = string.to_s
end

#threads(min, max = min) ⇒ Object

Configure the number of threads to use to answer requests.

It can be a single fixed number, or a min and a max.

The default is the environment variables PUMA_MIN_THREADS / PUMA_MAX_THREADS (or MIN_THREADS / MAX_THREADS if the PUMA_ variables aren’t set).

If these environment variables aren’t set, the default is “0, 5” in MRI or “0, 16” for other interpreters.

Examples:

threads 5
threads 0, 16
threads 5, 5


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# File 'lib/puma/dsl.rb', line 573

def threads(min, max = min)
  min = Integer(min)
  max = Integer(max)
  if min > max
    raise "The minimum (#{min}) number of threads must be less than or equal to the max (#{max})"
  end

  if max < 1
    raise "The maximum number of threads (#{max}) must be greater than 0"
  end

  @options[:min_threads] = min
  @options[:max_threads] = max
end

#wait_for_less_busy_worker(val = 0.005) ⇒ Object

Attempts to route traffic to less-busy workers by causing them to delay listening on the socket, allowing workers which are not processing any requests to pick up new requests first.

The default is 0.005 seconds.

Only works on MRI. For all other interpreters, this setting does nothing.

See Also:

Version:

  • 5.0.0



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# File 'lib/puma/dsl.rb', line 1179

def wait_for_less_busy_worker(val=0.005)
  @options[:wait_for_less_busy_worker] = val.to_f
end

#worker_boot_timeout(timeout) ⇒ Object

Note:

Cluster mode only.

Change the default worker timeout for booting.

The default is the value of ‘worker_timeout`.

Examples:

worker_boot_timeout 60

See Also:

  • Cluster::Worker#ping_timeout


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# File 'lib/puma/dsl.rb', line 1088

def worker_boot_timeout(timeout)
  @options[:worker_boot_timeout] = Integer(timeout)
end

#worker_check_interval(interval) ⇒ Object

Note:

Cluster mode only.

Change the default interval for checking workers.

The default is 5 seconds.

Examples:

worker_check_interval 10

See Also:



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# File 'lib/puma/dsl.rb', line 1046

def worker_check_interval(interval)
  @options[:worker_check_interval] = Integer(interval)
end

#worker_culling_strategy(strategy) ⇒ Object

Note:

Cluster mode only.

Set the strategy for worker culling.

There are two possible values:

  1. :youngest - the youngest workers (i.e. the workers that were the most recently started) will be culled.

  2. :oldest - the oldest workers (i.e. the workers that were started the longest time ago) will be culled.

The default is :youngest.

Examples:

worker_culling_strategy :oldest

See Also:



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# File 'lib/puma/dsl.rb', line 1125

def worker_culling_strategy(strategy)
  stategy = strategy.to_sym

  if ![:youngest, :oldest].include?(strategy)
    raise "Invalid value for worker_culling_strategy - #{stategy}"
  end

  @options[:worker_culling_strategy] = strategy
end

#worker_shutdown_timeout(timeout) ⇒ Object

Note:

Cluster mode only.

Set the timeout for worker shutdown.

The default is 60 seconds.

Examples:

worker_shutdown_timeout 90

See Also:

  • Cluster::Worker#term


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# File 'lib/puma/dsl.rb', line 1103

def worker_shutdown_timeout(timeout)
  @options[:worker_shutdown_timeout] = Integer(timeout)
end

#worker_timeout(timeout) ⇒ Object

Note:

Cluster mode only.

Verifies that all workers have checked in to the master process within the given timeout. If not the worker process will be restarted. This is not a request timeout, it is to protect against a hung or dead process. Setting this value will not protect against slow requests.

This value must be greater than worker_check_interval.

The default is 60 seconds.

Examples:

worker_timeout 60

See Also:

  • Cluster::Worker#ping_timeout


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# File 'lib/puma/dsl.rb', line 1066

def worker_timeout(timeout)
  timeout = Integer(timeout)
  min = @options.fetch(:worker_check_interval, Configuration::DEFAULTS[:worker_check_interval])

  if timeout <= min
    raise "The minimum worker_timeout must be greater than the worker reporting interval (#{min})"
  end

  @options[:worker_timeout] = timeout
end

#workers(count) ⇒ Object

Note:

Cluster mode only.

How many worker processes to run. Typically this is set to the number of available cores.

The default is the value of the environment variable WEB_CONCURRENCY if set, otherwise 0.

Examples:

workers 2

See Also:



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# File 'lib/puma/dsl.rb', line 676

def workers(count)
  @options[:workers] = count.to_i
end