class Puma::DSL

Convenience method so logic can be used in CI.

@see ssl_bind

# File lib/puma/dsl.rb, line 59
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

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 {Puma::App::Status} to see what the app has available.

@example

activate_control_app 'unix:///var/run/pumactl.sock'

@example

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

@example

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

# File lib/puma/dsl.rb, line 220
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

Code to run after puma is booted (works for both single and cluster modes).

@example

after_booted do
  puts 'After booting...'
end

# File lib/puma/dsl.rb, line 843
def after_booted(&block)
  Puma.deprecate_method_change :on_booted, __callee__, __method__

  @config.events.after_booted(&block)
end

When ‘fork_worker` is enabled, code to run in Worker 0 after 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 re-open any connections to remote servers (database, Redis, …) that were closed via before_refork.

This can be called multiple times to add several hooks.

@note Cluster mode with ‘fork_worker` enabled only.

@example

after_refork do
  puts 'After refork...'
end

# File lib/puma/dsl.rb, line 910
def after_refork(key = nil, &block)
  process_hook :after_refork, key, block
end

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

@example

after_stopped do
  puts 'After stopping...'
end

# File lib/puma/dsl.rb, line 858
def after_stopped(&block)
  Puma.deprecate_method_change :on_stopped, __callee__, __method__

  @config.events.after_stopped(&block)
end

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.

@note Cluster mode only.

@example

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

# File lib/puma/dsl.rb, line 816
def after_worker_fork(&block)
  process_hook :after_worker_fork, nil, block, cluster_only: true
end

Code to run in the master right after a worker has stopped. The worker’s index and Process::Status are passed as arguments.

@note Cluster mode only.

@example

after_worker_shutdown do |worker_handle|
  puts 'Worker crashed' unless worker_handle.process_status.success?
end

# File lib/puma/dsl.rb, line 832
def after_worker_shutdown(&block)
  process_hook :after_worker_shutdown, nil, block, cluster_only: true
end

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

@example

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

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

@see Puma::Configuration#app

# File lib/puma/dsl.rb, line 197
def app(obj=nil, &block)
  obj ||= block

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

  @options[:app] = obj
end

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.

@note Cluster mode only.

@example

before_fork do
  puts "Starting workers..."
end

# File lib/puma/dsl.rb, line 737
def before_fork(&block)
  process_hook :before_fork, nil, block, cluster_only: true
end

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.

@note Cluster mode with ‘fork_worker` enabled only.

@example

before_refork do
  3.times {GC.start}
end

@version 5.0.0

# File lib/puma/dsl.rb, line 885
def before_refork(key = nil, &block)
  Puma.deprecate_method_change :on_refork, __callee__, __method__

  process_hook :before_refork, key, block, cluster_only: true
end

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.

@example

before_restart do
  puts 'On restart...'
end

# File lib/puma/dsl.rb, line 444
def before_restart(&block)
  Puma.deprecate_method_change :on_restart, __callee__, __method__

  process_hook :before_restart, nil, block
end

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.

@example

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

# File lib/puma/dsl.rb, line 959
def before_thread_exit(&block)
  Puma.deprecate_method_change :on_thread_exit, __callee__, __method__

  process_hook :before_thread_exit, nil, block
end

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.

@example

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

# File lib/puma/dsl.rb, line 931
def before_thread_start(&block)
  Puma.deprecate_method_change :on_thread_start, __callee__, __method__

  process_hook :before_thread_start, nil, block
end

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.

@note Cluster mode only.

@example

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

# File lib/puma/dsl.rb, line 753
def before_worker_boot(key = nil, &block)
  Puma.deprecate_method_change :on_worker_boot, __callee__, __method__

  process_hook :before_worker_boot, key, block, cluster_only: true
end

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.

@note Cluster mode only.

@example

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

# File lib/puma/dsl.rb, line 796
def before_worker_fork(&block)
  Puma.deprecate_method_change :on_worker_fork, __callee__, __method__

  process_hook :before_worker_fork, nil, block, cluster_only: true
end

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.

@note Cluster mode only.

@example

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

# File lib/puma/dsl.rb, line 776
def before_worker_shutdown(key = nil, &block)
  Puma.deprecate_method_change :on_worker_shutdown, __callee__, __method__

  process_hook :before_worker_shutdown, key, block, cluster_only: true
end

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.

@example Backlog depth

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

@example SSL cert

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

@example 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'

@example Disable optimization for low latency

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

@example Socket permissions

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

@see Puma::Runner#load_and_bind @see Puma::Cluster#run

# File lib/puma/dsl.rb, line 286
def bind(url)
  @options[:binds] ||= []
  @options[:binds] << url
end

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.

@example Use any systemd activated sockets as well as configured binds

bind_to_activated_sockets

@example Only bind to systemd activated sockets, ignoring other binds

bind_to_activated_sockets 'only'

# File lib/puma/dsl.rb, line 318
def bind_to_activated_sockets(bind=true)
  @options[:bind_to_activated_sockets] = bind
end

Pass in a custom logging class instance

@example

custom_logger Logger.new('t.log')

# File lib/puma/dsl.rb, line 499
def custom_logger(custom_logger)
  @options[:custom_logger] = custom_logger
end

Show debugging info

The default is false.

@example

debug

# File lib/puma/dsl.rb, line 510
def debug
  @options[:debug] = true
end

The directory to operate out of.

The default is the current directory.

@example

directory '/u/apps/lolcat'

# File lib/puma/dsl.rb, line 988
def directory(dir)
  @options[:directory] = dir.to_s
end

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 Puma::Server#graceful_shutdown

# File lib/puma/dsl.rb, line 394
def drain_on_shutdown(which=true)
  @options[:drain_on_shutdown] = which
end

Enable HTTP 103 Early Hints responses.

The default is nil.

@example

early_hints

# File lib/puma/dsl.rb, line 540
def early_hints(answer=true)
  @options[:early_hints] = answer
end

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.

@example

enable_keep_alives false

# File lib/puma/dsl.rb, line 1364
def enable_keep_alives(enabled=true)
  @options[:enable_keep_alives] = enabled
end

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

The default is “development”.

@example

environment 'production'

# File lib/puma/dsl.rb, line 406
def environment(environment)
  @options[:environment] = environment
end

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.

@example

extra_runtime_dependencies ['gem_name_1', 'gem_name_2']

@example

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

@see Puma::Launcher#extra_runtime_deps_directories

# File lib/puma/dsl.rb, line 1074
def extra_runtime_dependencies(answer = [])
  @options[:extra_runtime_dependencies] = Array(answer)
end

Use a clean fiber per request which ensures a clean slate for fiber locals and fiber storage. Also provides a cleaner backtrace with less Puma internal stack frames.

The default is false.

@example

fiber_per_request

# File lib/puma/dsl.rb, line 382
def fiber_per_request(which=true)
  @options[:fiber_per_request] = which
end

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

The default is 30 seconds.

@example

first_data_timeout 40

@see Puma::Server.new

# File lib/puma/dsl.rb, line 343
def first_data_timeout(seconds)
  @options[:first_data_timeout] = Integer(seconds)
end

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 Puma::Server#graceful_shutdown

# File lib/puma/dsl.rb, line 421
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

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.

@note This is experimental. @note Cluster mode only.

# File lib/puma/dsl.rb, line 1318
def fork_worker(after_requests=1000)
  @options[:fork_worker] = Integer(after_requests)
end

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.

@example

http_content_length_limit 2_000_000_000

# File lib/puma/dsl.rb, line 1412
def http_content_length_limit(limit)
  @options[:http_content_length_limit] = limit
end

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

The default is nil.

@example

idle_timeout 60

@see Puma::Server.new

# File lib/puma/dsl.rb, line 369
def idle_timeout(seconds)
  @options[:idle_timeout] = Integer(seconds)
end

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 github.com/socketry/nio4r/blob/master/lib/nio/selector.rb

# File lib/puma/dsl.rb, line 1383
def io_selector_backend(backend)
  @options[:io_selector_backend] = backend.to_sym
end

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

@example

load 'config/puma/production.rb'

# File lib/puma/dsl.rb, line 251
def load(file)
  @options[:config_files] ||= []
  @options[:config_files] << file
end

Enable request logging, the inverse of ‘quiet`.

The default is false.

@example

log_requests

# File lib/puma/dsl.rb, line 490
def log_requests(which=true)
  @options[:log_requests] = which
end

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

@example

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

# File lib/puma/dsl.rb, line 1014
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

@deprecated Use {#max_keep_alive} instead.

# File lib/puma/dsl.rb, line 1324
def max_fast_inline(num_of_requests)
  Puma.deprecate_method_change :max_fast_inline, __method__, :max_keep_alive
  @options[:max_keep_alive] ||= Float(num_of_requests) unless num_of_requests.nil?
end

The number of requests a keep-alive client can submit before being closed. Note that some applications (server to server) may benefit from a very high number or Float::INFINITY.

The default is 999.

@example

max_keep_alive 20

# File lib/puma/dsl.rb, line 1338
def max_keep_alive(num_of_requests)
  @options[:max_keep_alive] = Float(num_of_requests) unless num_of_requests.nil?
end

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

The default is true.

@example

mutate_stdout_and_stderr_to_sync_on_write false

# File lib/puma/dsl.rb, line 1395
def mutate_stdout_and_stderr_to_sync_on_write(enabled=true)
  @options[:mutate_stdout_and_stderr_to_sync_on_write] = enabled
end

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.

# File lib/puma/dsl.rb, line 977
def out_of_band(&block)
  process_hook :out_of_band, nil, block
end

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

The default is 20 seconds.

@example

persistent_timeout 30

@see Puma::Server.new

# File lib/puma/dsl.rb, line 356
def persistent_timeout(seconds)
  @options[:persistent_timeout] = Integer(seconds)
end

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

@example

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

# File lib/puma/dsl.rb, line 468
def pidfile(path)
  @options[:pidfile] = path.to_s
end

Load the named plugin for use by this configuration.

@example

plugin :tmp_restart

# File lib/puma/dsl.rb, line 174
def plugin(name)
  @plugins << @config.load_plugin(name)
end

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

The default is 9292.

@example

port 3000

# File lib/puma/dsl.rb, line 329
def port(port, host=nil)
  host ||= default_host
  bind URI::Generic.build(scheme: 'tcp', host: host, port: Integer(port)).to_s
end

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

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

@note Cluster mode only.

@example

preload_app!

# File lib/puma/dsl.rb, line 1002
def preload_app!(answer=true)
  @options[:preload_app] = answer
end

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.

@note This is incompatible with preload_app!. @note This is only supported for RubyGems 2.2+

@see extra_runtime_dependencies

# File lib/puma/dsl.rb, line 1038
def prune_bundler(answer=true)
  @options[:prune_bundler] = answer
end

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 Puma::Server

# File lib/puma/dsl.rb, line 1212
def queue_requests(answer=true)
  @options[:queue_requests] = answer
end

Disable request logging, the inverse of ‘log_requests`.

The default is true.

@example

quiet

# File lib/puma/dsl.rb, line 479
def quiet(which=true)
  @options[:log_requests] = !which
end

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

# File lib/puma/dsl.rb, line 529
def rack_url_scheme(scheme=nil)
  @options[:rack_url_scheme] = scheme
end

Load path as a rackup file.

The default is “config.ru”.

@example

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

# File lib/puma/dsl.rb, line 521
def rackup(path)
  @options[:rackup] ||= path.to_s
end

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.

@example

raise_exception_on_sigterm false

@see Puma::Launcher#setup_signals @see Puma::Cluster#setup_signals

# File lib/puma/dsl.rb, line 1056
def raise_exception_on_sigterm(answer=true)
  @options[:raise_exception_on_sigterm] = answer
end

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.

@example

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

# File lib/puma/dsl.rb, line 459
def restart_command(cmd)
  @options[:restart_cmd] = cmd.to_s
end

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.

@example

set_remote_address :localhost

# File lib/puma/dsl.rb, line 1276
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

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.

# File lib/puma/dsl.rb, line 1220
def shutdown_debug(val=true)
  @options[:shutdown_debug] = val
end

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

The default is false.

@example

silence_fork_callback_warning

# File lib/puma/dsl.rb, line 717
def silence_fork_callback_warning
  @options[:silence_fork_callback_warning] = true
end

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.

@note Cluster mode only.

@example

silence_single_worker_warning

# File lib/puma/dsl.rb, line 706
def silence_single_worker_warning
  @options[:silence_single_worker_warning] = true
end

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.

@example

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
}

@example Using self-signed certificate with the localhost gem:

ssl_bind '127.0.0.1', '9292'

@example 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
}

@example 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'
}

# File lib/puma/dsl.rb, line 644
def ssl_bind(host, port, opts = {})
  add_pem_values_to_options_store(opts)
  bind self.class.ssl_bind_str(host, port, opts)
end

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

@example

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

# File lib/puma/dsl.rb, line 655
def state_path(path)
  @options[:state] = path.to_s
end

Use permission to restrict permissions for the state file. By convention, permission is an octal number (e.g. ‘0640` or `0o640`).

@example

state_permission 0600

# File lib/puma/dsl.rb, line 665
def state_permission(permission)
  @options[:state_permission] = permission
end

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

The default is false.

@example

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

@example

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

# File lib/puma/dsl.rb, line 554
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, 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`.

@note If the ‘methods` value is `:any`, no method check with be performed,

similar to Puma v5 and earlier.

@example Adds ‘PROPFIND’ to existing supported methods

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

@example Restricts methods to the array elements

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

@example Restricts methods to the methods in the IANA Registry

supported_http_methods Puma::Const::IANA_HTTP_METHODS

@example Allows any method

supported_http_methods :any

# File lib/puma/dsl.rb, line 1437
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

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.

@example

tag 'app name'

@example

tag ''

# File lib/puma/dsl.rb, line 1090
def tag(string)
  @options[:tag] = string.to_s
end

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.

@example

threads 5

@example

threads 0, 16

@example

threads 5, 5

# File lib/puma/dsl.rb, line 580
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

Maximum delay of worker accept loop.

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

The default is 0.005 seconds.

To turn off this feature, set the value to 0.

@note Cluster mode with >= 2 workers only.

@note Interpreters with forking support only.

@see Puma::Server#handle_servers @see Puma::ThreadPool#wait_for_less_busy_worker

# File lib/puma/dsl.rb, line 1242
def wait_for_less_busy_worker(val=0.005)
  @options[:wait_for_less_busy_worker] = val.to_f
end

Change the default worker timeout for booting.

The default is the value of ‘worker_timeout`.

@note Cluster mode only.

@example

worker_boot_timeout 60

@see Puma::Cluster::Worker#ping_timeout

# File lib/puma/dsl.rb, line 1147
def worker_boot_timeout(timeout)
  @options[:worker_boot_timeout] = Integer(timeout)
end

Change the default interval for checking workers.

The default is 5 seconds.

@note Cluster mode only.

@example

worker_check_interval 10

@see Puma::Cluster#check_workers

# File lib/puma/dsl.rb, line 1105
def worker_check_interval(interval)
  @options[:worker_check_interval] = Integer(interval)
end

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.

@note Cluster mode only.

@example

worker_culling_strategy :oldest

@see Puma::Cluster#cull_workers

# File lib/puma/dsl.rb, line 1184
def worker_culling_strategy(strategy)
  strategy = strategy.to_sym

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

  @options[:worker_culling_strategy] = strategy
end

Set the timeout for worker shutdown.

The default is 30 seconds.

@note Cluster mode only.

@example

worker_shutdown_timeout 90

@see Puma::Cluster::Worker#term

# File lib/puma/dsl.rb, line 1162
def worker_shutdown_timeout(timeout)
  @options[:worker_shutdown_timeout] = Integer(timeout)
end

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.

@note Cluster mode only.

@example

worker_timeout 60

@see Puma::Cluster::Worker#ping_timeout

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

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.

@note Cluster mode only.

@example

workers 2

@see Puma::Cluster

# File lib/puma/dsl.rb, line 682
def workers(count)
  @options[:workers] = count.to_i
end

To avoid adding cert_pem and key_pem as URI params, we store them on the options from where Puma binder knows how to find and extract them.

# File lib/puma/dsl.rb, line 1453
def add_pem_values_to_options_store(opts)
  return if defined?(JRUBY_VERSION)

  @options[:store] ||= []

  # Store cert_pem and key_pem to options[:store] if present
  [:cert, :key].each do |v|
    opt_key = :"#{v}_pem"
    if opts[opt_key]
      index = @options[:store].length
      @options[:store] << opts[opt_key]
      opts[v] = "store:#{index}"
    end
  end
end