class Puma::DSL

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 {Puma::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              |

Constants

ON_WORKER_KEY

Public Class Methods

new(options, config) click to toggle source
# File lib/puma/dsl.rb, line 123
def initialize(options, config)
  @config  = config
  @options = options

  @plugins = []
end
ssl_bind_str(host, port, opts) click to toggle source

convenience method so logic can be used in CI @see ssl_bind

# File lib/puma/dsl.rb, line 57
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
    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}" \
      "#{reuse_flag}&verify_mode=#{verify}#{tls_str}#{ca_additions}#{v_flags}#{backlog_str}#{low_latency_str}"
  end
end

Public Instance Methods

_load_from(path) click to toggle source
# File lib/puma/dsl.rb, line 130
def _load_from(path)
  if path
    @path = path
    instance_eval(File.read(path), path, 1)
  end
ensure
  _offer_plugins
end
_offer_plugins() click to toggle source
# File lib/puma/dsl.rb, line 139
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={}) click to toggle source

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 213
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_boot(&block)
Alias for: after_worker_fork
after_worker_fork(&block) click to toggle source

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 692
def after_worker_fork(&block)
  warn_if_in_single_mode('after_worker_fork')

  process_hook :after_worker_fork, nil, block, 'after_worker_fork'
end
Also aliased as: after_worker_boot
app(obj=nil, &block) click to toggle source

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 191
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) click to toggle source

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 625
def before_fork(&block)
  warn_if_in_single_mode('before_fork')

  @options[:before_fork] ||= []
  @options[:before_fork] << block
end
bind(url) click to toggle source

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 274
def bind(url)
  @options[:binds] ||= []
  @options[:binds] << url
end
bind_to_activated_sockets(bind=true) click to toggle source

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 305
def bind_to_activated_sockets(bind=true)
  @options[:bind_to_activated_sockets] = bind
end
clean_thread_locals(which=true) click to toggle source

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

# File lib/puma/dsl.rb, line 338
def clean_thread_locals(which=true)
  @options[:clean_thread_locals] = which
end
clear_binds!() click to toggle source
# File lib/puma/dsl.rb, line 279
def clear_binds!
  @options[:binds] = []
end
custom_logger(custom_logger) click to toggle source

Pass in a custom logging class instance

# File lib/puma/dsl.rb, line 430
def custom_logger(custom_logger)
  @options[:custom_logger] = custom_logger
end
debug() click to toggle source

Show debugging info

# File lib/puma/dsl.rb, line 436
def debug
  @options[:debug] = true
end
default_host() click to toggle source
# File lib/puma/dsl.rb, line 154
def default_host
  @options[:default_host] || Configuration::DEFAULTS[:tcp_host]
end
directory(dir) click to toggle source

The directory to operate out of.

The default is the current directory.

@example

directory '/u/apps/lolcat'
# File lib/puma/dsl.rb, line 796
def directory(dir)
  @options[:directory] = dir.to_s
end
drain_on_shutdown(which=true) click to toggle source

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 347
def drain_on_shutdown(which=true)
  @options[:drain_on_shutdown] = which
end
early_hints(answer=true) click to toggle source
# File lib/puma/dsl.rb, line 457
def early_hints(answer=true)
  @options[:early_hints] = answer
end
environment(environment) click to toggle source

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 358
def environment(environment)
  @options[:environment] = environment
end
extra_runtime_dependencies(answer = []) click to toggle source

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 873
def extra_runtime_dependencies(answer = [])
  @options[:extra_runtime_dependencies] = Array(answer)
end
first_data_timeout(seconds) click to toggle source

Define how long the tcp socket stays open, if no data has been received. @see Puma::Server.new

# File lib/puma/dsl.rb, line 320
def first_data_timeout(seconds)
  @options[:first_data_timeout] = Integer(seconds)
end
force_shutdown_after(val=:forever) click to toggle source

How long to wait for threads to stop when shutting them down. Defaults to :forever. 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. @see Puma::Server#graceful_shutdown

# File lib/puma/dsl.rb, line 370
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) click to toggle source

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 Cluster mode only. @version 5.0.0

# File lib/puma/dsl.rb, line 1081
def fork_worker(after_requests=1000)
  @options[:fork_worker] = Integer(after_requests)
end
get(key,default=nil) click to toggle source
# File lib/puma/dsl.rb, line 162
def get(key,default=nil)
  @options[key.to_sym] || default
end
http_content_length_limit(limit) click to toggle source

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 value for http_content_length_limit is nil.

# File lib/puma/dsl.rb, line 1124
def http_content_length_limit(limit)
  @options[:http_content_length_limit] = limit
end
idle_timeout(seconds) click to toggle source

If a new request is not received within this number of seconds, begin shutting down. @see Puma::Server.new

# File lib/puma/dsl.rb, line 332
def idle_timeout(seconds)
  @options[:idle_timeout] = Integer(seconds)
end
inject(&blk) click to toggle source
# File lib/puma/dsl.rb, line 158
def inject(&blk)
  instance_eval(&blk)
end
io_selector_backend(backend) click to toggle source

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 1107
def io_selector_backend(backend)
  @options[:io_selector_backend] = backend.to_sym
end
load(file) click to toggle source

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

# File lib/puma/dsl.rb, line 240
def load(file)
  @options[:config_files] ||= []
  @options[:config_files] << file
end
log_formatter(&block) click to toggle source
# File lib/puma/dsl.rb, line 474
def log_formatter(&block)
  @options[:log_formatter] = block
end
log_requests(which=true) click to toggle source

Enable request logging

# File lib/puma/dsl.rb, line 425
def log_requests(which=true)
  @options[:log_requests] = which
end
lowlevel_error_handler(obj=nil, &block) click to toggle source

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 817
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) click to toggle source

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

# File lib/puma/dsl.rb, line 1088
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) click to toggle source
# File lib/puma/dsl.rb, line 1111
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) click to toggle source

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

@example

on_booted do
  puts 'After booting...'
end
# File lib/puma/dsl.rb, line 706
def on_booted(&block)
  @config.options[:events].on_booted(&block)
end
on_refork(key = nil, &block) click to toggle source

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

on_refork do
  3.times {GC.start}
end

@version 5.0.0

# File lib/puma/dsl.rb, line 728
def on_refork(key = nil, &block)
  process_hook :before_refork, key, block, 'on_refork'
end
on_restart(&block) click to toggle source

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

on_restart do
  puts 'On restart...'
end
# File lib/puma/dsl.rb, line 392
def on_restart(&block)
  @options[:on_restart] ||= []
  @options[:on_restart] << block
end
on_thread_exit(&block) click to toggle source

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

on_thread_exit do
  puts 'On thread exit...'
end
# File lib/puma/dsl.rb, line 772
def on_thread_exit(&block)
  @options[:before_thread_exit] ||= []
  @options[:before_thread_exit] << block
end
on_thread_start(&block) click to toggle source

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

on_thread_start do
  puts 'On thread start...'
end
# File lib/puma/dsl.rb, line 748
def on_thread_start(&block)
  @options[:before_thread_start] ||= []
  @options[:before_thread_start] << block
end
on_worker_boot(key = nil, &block) click to toggle source

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

on_worker_boot do
  puts 'Before worker boot...'
end
# File lib/puma/dsl.rb, line 642
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) click to toggle source

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

on_worker_fork do
  puts 'Before worker fork...'
end
# File lib/puma/dsl.rb, line 676
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) click to toggle source

Code to run immediately before a worker shuts down (after it has finished processing HTTP requests). 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

on_worker_shutdown do
  puts 'On worker shutdown...'
end
# File lib/puma/dsl.rb, line 660
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) click to toggle source

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 786
def out_of_band(&block)
  process_hook :out_of_band, nil, block, 'out_of_band'
end
persistent_timeout(seconds) click to toggle source

Define how long persistent connections can be idle before Puma closes them. @see Puma::Server.new

# File lib/puma/dsl.rb, line 326
def persistent_timeout(seconds)
  @options[:persistent_timeout] = Integer(seconds)
end
pidfile(path) click to toggle source

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 411
def pidfile(path)
  @options[:pidfile] = path.to_s
end
plugin(name) click to toggle source

Load the named plugin for use by this configuration

# File lib/puma/dsl.rb, line 168
def plugin(name)
  @plugins << @config.load_plugin(name)
end
port(port, host=nil) click to toggle source

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

@example

port 9292
# File lib/puma/dsl.rb, line 313
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) click to toggle source

Preload the application before starting the workers; this conflicts with phased restart feature. On by default if your app uses more than 1 worker.

@note Cluster mode only. @example

preload_app!
# File lib/puma/dsl.rb, line 806
def preload_app!(answer=true)
  @options[:preload_app] = answer
end
prune_bundler(answer=true) click to toggle source

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 extra_runtime_dependencies

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

# File lib/puma/dsl.rb, line 840
def prune_bundler(answer=true)
  @options[:prune_bundler] = answer
end
queue_requests(answer=true) click to toggle source

When set to true (the default), 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. @see Puma::Server

# File lib/puma/dsl.rb, line 988
def queue_requests(answer=true)
  @options[:queue_requests] = answer
end
quiet(which=true) click to toggle source

Disable request logging, if this isn't used it'll be enabled by default.

@example

quiet
# File lib/puma/dsl.rb, line 419
def quiet(which=true)
  @options[:log_requests] = !which
end
rack_url_scheme(scheme=nil) click to toggle source

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 453
def rack_url_scheme(scheme=nil)
  @options[:rack_url_scheme] = scheme
end
rackup(path) click to toggle source

Load path as a rackup file.

The default is “config.ru”.

@example

rackup '/u/apps/lolcat/config.ru'
# File lib/puma/dsl.rb, line 446
def rackup(path)
  @options[:rackup] ||= path.to_s
end
raise_exception_on_sigterm(answer=true) click to toggle source

By default, Puma will raise 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 infrastructure level.

@example

raise_exception_on_sigterm false

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

# File lib/puma/dsl.rb, line 856
def raise_exception_on_sigterm(answer=true)
  @options[:raise_exception_on_sigterm] = answer
end
restart_command(cmd) click to toggle source

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 403
def restart_command(cmd)
  @options[:restart_cmd] = cmd.to_s
end
set_default_host(host) click to toggle source
# File lib/puma/dsl.rb, line 150
def set_default_host(host)
  @options[:default_host] = host
end
set_remote_address(val=:socket) click to toggle source

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 (the default) - 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.

# File lib/puma/dsl.rb, line 1039
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) click to toggle source

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 996
def shutdown_debug(val=true)
  @options[:shutdown_debug] = val
end
silence_fork_callback_warning() click to toggle source

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

# File lib/puma/dsl.rb, line 607
def silence_fork_callback_warning
  @options[:silence_fork_callback_warning] = true
end
silence_single_worker_warning() click to toggle source

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.

@note Cluster mode only.

# File lib/puma/dsl.rb, line 602
def silence_single_worker_warning
  @options[:silence_single_worker_warning] = true
end
ssl_bind(host, port, opts = {}) click to toggle source

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
  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 552
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) click to toggle source

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 562
def state_path(path)
  @options[:state] = path.to_s
end
state_permission(permission) click to toggle source

Use permission to restrict permissions for the state file.

@example

state_permission 0600

@version 5.0.0

# File lib/puma/dsl.rb, line 572
def state_permission(permission)
  @options[:state_permission] = permission
end
stdout_redirect(stdout=nil, stderr=nil, append=false) click to toggle source

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 468
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) click to toggle source

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 1149
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) click to toggle source

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.

@example

tag 'app name'

@example

tag ''
# File lib/puma/dsl.rb, line 886
def tag(string)
  @options[:tag] = string.to_s
end
threads(min, max) click to toggle source

Configure min to be the minimum number of threads to use to answer requests and max the maximum.

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 0, 16

@example

threads 5, 5
# File lib/puma/dsl.rb, line 490
def threads(min, max)
  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) click to toggle source

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.

Only works on MRI. For all other interpreters, this setting does nothing. @see Puma::Server#handle_servers @see Puma::ThreadPool#wait_for_less_busy_worker @version 5.0.0

# File lib/puma/dsl.rb, line 1010
def wait_for_less_busy_worker(val=0.005)
  @options[:wait_for_less_busy_worker] = val.to_f
end
worker_boot_timeout(timeout) click to toggle source

Change the default worker timeout for booting.

If unspecified, this defaults to 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 937
def worker_boot_timeout(timeout)
  @options[:worker_boot_timeout] = Integer(timeout)
end
worker_check_interval(interval) click to toggle source

Change the default interval for checking workers.

The default value is 5 seconds.

@note Cluster mode only. @example

worker_check_interval 5

@see Puma::Cluster#check_workers

# File lib/puma/dsl.rb, line 899
def worker_check_interval(interval)
  @options[:worker_check_interval] = Integer(interval)
end
worker_culling_strategy(strategy) click to toggle source

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.

@note Cluster mode only. @example

worker_culling_strategy :oldest

@see Puma::Cluster#cull_workers

# File lib/puma/dsl.rb, line 964
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) click to toggle source

Set the timeout for worker shutdown.

@note Cluster mode only. @see Puma::Cluster::Worker#term

# File lib/puma/dsl.rb, line 946
def worker_shutdown_timeout(timeout)
  @options[:worker_shutdown_timeout] = Integer(timeout)
end
worker_timeout(timeout) click to toggle source

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 value is 60 seconds.

@note Cluster mode only. @example

worker_timeout 60

@see Puma::Cluster::Worker#ping_timeout

# File lib/puma/dsl.rb, line 916
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) click to toggle source

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. @see Puma::Cluster

# File lib/puma/dsl.rb, line 584
def workers(count)
  @options[:workers] = count.to_i
end

Private Instance Methods

add_pem_values_to_options_store(opts) click to toggle source

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 1164
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
process_hook(options_key, key, block, meth) click to toggle source
# File lib/puma/dsl.rb, line 1180
def process_hook(options_key, key, block, meth)
  @options[options_key] ||= []
  if ON_WORKER_KEY.include? key.class
    @options[options_key] << [block, key.to_sym]
  elsif key.nil?
    @options[options_key] << block
  else
    raise "'#{meth}' key must be String or Symbol"
  end
end
warn_if_in_single_mode(hook_name) click to toggle source
# File lib/puma/dsl.rb, line 1191
def warn_if_in_single_mode(hook_name)
  return if @options[:silence_fork_callback_warning]
  # user_options (CLI) have precedence over config file
  workers_val = @config.options.user_options[:workers] || @options[:workers] ||
    @config.puma_default_options[:workers] || 0
  if workers_val == 0
    log_string =
      "Warning: You specified code to run in a `#{hook_name}` block, " \
      "but Puma is not configured to run in cluster mode (worker count > 0 ), " \
      "so your `#{hook_name}` block did not run"

    LogWriter.stdio.log(log_string)
  end
end