Guides.rubyonrails.org

version = ">= 0"
load Gem.bin_path('railties', 'rails', version)

require "rails/cli"

$ exec ruby bin/rails server

#!/usr/bin/env ruby
APP_PATH = File.expand_path('../../config/application', __FILE__)
require_relative '../config/boot'
require 'rails/commands'

ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)

require 'bundler/setup' # 设置 Gemfile 中列出的所有 gem

ARGV << '--help' if ARGV.empty?

aliases = {
  "g"  => "generate",
  "d"  => "destroy",
  "c"  => "console",
  "s"  => "server",
  "db" => "dbconsole",
  "r"  => "runner",
  "t"  => "test"
}

command = ARGV.shift
command = aliases[command] || command

require 'rails/commands/commands_tasks'

Rails::CommandsTasks.new(ARGV).run_command!(command)

COMMAND_WHITELIST = %w(plugin generate destroy console server dbconsole application runner new version help)

def run_command!(command)
  command = parse_command(command)

  if COMMAND_WHITELIST.include?(command)
    send(command)
  else
    run_rake_task(command)
  end
end

def set_application_directory!
  Dir.chdir(File.expand_path('../../', APP_PATH)) unless File.exist?(File.expand_path("config.ru"))
end

def server
  set_application_directory!
  require_command!("server")

  Rails::Server.new.tap do |server|
    # 当服务器完成环境设置后，就需要加载应用，
    # 否则传递给服务器的 `--environment` 选项就不会继续传递下去。
    require APP_PATH
    Dir.chdir(Rails.application.root)
    server.start
  end
end

def require_command!(command)
  require "rails/commands/#{command}"
end

require 'fileutils'
require 'optparse'
require 'action_dispatch'
require 'rails'

module Rails
  class Server < ::Rack::Server

def initialize(*)
  super
  set_environment
end

def initialize(options = nil)
  @options = options
  @app = options[:app] if options && options[:app]
end

def set_environment
  ENV["RAILS_ENV"] ||= options[:environment]
end

def options
  @options ||= parse_options(ARGV)
end

def parse_options(args)
  options = default_options

  # 请不要计算 CGI `ISINDEX` 参数的值。
  # http://www.meb.uni-bonn.de/docs/cgi/cl.html
  args.clear if ENV.include?("REQUEST_METHOD")

  options.merge! opt_parser.parse!(args)
  options[:config] = ::File.expand_path(options[:config])
  ENV["RACK_ENV"] = options[:environment]
  options
end

def default_options
  environment  = ENV['RACK_ENV'] || 'development'
  default_host = environment == 'development' ? 'localhost' : '0.0.0.0'

  {
    :environment => environment,
    :pid         => nil,
    :Port        => 9292,
    :Host        => default_host,
    :AccessLog   => [],
    :config      => "config.ru"
  }
end

def opt_parser
  Options.new
end

def parse!(args)
  args, options = args.dup, {}

  opt_parser = OptionParser.new do |opts|
    opts.banner = "Usage: rails server [mongrel, thin, etc] [options]"
    opts.on("-p", "--port=port", Integer,
            "Runs Rails on the specified port.", "Default: 3000") { |v| options[:Port] = v }
  ...

def start
  print_boot_information
  trap(:INT) { exit }
  create_tmp_directories
  log_to_stdout if options[:log_stdout]

  super
  ...
end

private

  def print_boot_information
    ...
    puts "=> Run `rails server -h` for more startup options"
  end

  def create_tmp_directories
    %w(cache pids sockets).each do |dir_to_make|
      FileUtils.mkdir_p(File.join(Rails.root, 'tmp', dir_to_make))
    end
  end

  def log_to_stdout
    wrapped_app # 对应用执行 touch 操作，以便设置记录器

    console = ActiveSupport::Logger.new($stdout)
    console.formatter = Rails.logger.formatter
    console.level = Rails.logger.level

    Rails.logger.extend(ActiveSupport::Logger.broadcast(console))
  end

def start &blk
  if options[:warn]
    $-w = true
  end

  if includes = options[:include]
    $LOAD_PATH.unshift(*includes)
  end

  if library = options[:require]
    require library
  end

  if options[:debug]
    $DEBUG = true
    require 'pp'
    p options[:server]
    pp wrapped_app
    pp app
  end

  check_pid! if options[:pid]

  # 对包装后的应用执行 touch 操作，以便在创建守护进程之前
  # 加载 `config.ru` 文件（例如在 `chdir` 等操作之前）
  wrapped_app

  daemonize_app if options[:daemonize]

  write_pid if options[:pid]

  trap(:INT) do
    if server.respond_to?(:shutdown)
      server.shutdown
    else
      exit
    end
  end

  server.run wrapped_app, options, &blk
end

@wrapped_app ||= build_app app

def app
  @app ||= options[:builder] ? build_app_from_string : build_app_and_options_from_config
end
...
private
  def build_app_and_options_from_config
    if !::File.exist? options[:config]
      abort "configuration #{options[:config]} not found"
    end

    app, options = Rack::Builder.parse_file(self.options[:config], opt_parser)
    self.options.merge! options
    app
  end

  def build_app_from_string
    Rack::Builder.new_from_string(self.options[:builder])
  end

# 基于 Rack 的服务器使用此文件来启动应用。

require ::File.expand_path('../config/environment', __FILE__)
run <%= app_const %>

app = new_from_string cfgfile, config

...

def self.new_from_string(builder_script, file="(rackup)")
  eval "Rack::Builder.new {\n" + builder_script + "\n}.to_app",
    TOPLEVEL_BINDING, file, 0
end

require ::File.expand_path('../config/environment', __FILE__)

require File.expand_path('../application', __FILE__)

require File.expand_path('../boot', __FILE__)

require 'rails/all'

require "rails"

%w(
  active_record/railtie
  action_controller/railtie
  action_view/railtie
  action_mailer/railtie
  active_job/railtie
  action_cable/engine
  rails/test_unit/railtie
  sprockets/railtie
).each do |railtie|
  begin
    require "#{railtie}"
  rescue LoadError
  end
end

def initialize!(group=:default) #:nodoc:
  raise "Application has been already initialized." if @initialized
  run_initializers(group, self)
  @initialized = true
  self
end

def run_initializers(group=:default, *args)
  return if instance_variable_defined?(:@ran)
  initializers.tsort_each do |initializer|
    initializer.run(*args) if initializer.belongs_to?(group)
  end
  @ran = true
end

def app
  @app ||= options[:builder] ? build_app_from_string : build_app_and_options_from_config
end
...
private
  def build_app_and_options_from_config
    if !::File.exist? options[:config]
      abort "configuration #{options[:config]} not found"
    end

    app, options = Rack::Builder.parse_file(self.options[:config], opt_parser)
    self.options.merge! options
    app
  end

  def build_app_from_string
    Rack::Builder.new_from_string(self.options[:builder])
  end

def build_app(app)
  middleware[options[:environment]].reverse_each do |middleware|
    middleware = middleware.call(self) if middleware.respond_to?(:call)
    next unless middleware
    klass = middleware.shift
    app = klass.new(app, *middleware)
  end
  app
end

server.run wrapped_app, options, &blk

...
DEFAULT_OPTIONS = {
  :Host => '0.0.0.0',
  :Port => 8080,
  :Threads => '0:16',
  :Verbose => false
}

def self.run(app, options = {})
  options  = DEFAULT_OPTIONS.merge(options)

  if options[:Verbose]
    app = Rack::CommonLogger.new(app, STDOUT)
  end

  if options[:environment]
    ENV['RACK_ENV'] = options[:environment].to_s
  end

  server   = ::Puma::Server.new(app)
  min, max = options[:Threads].split(':', 2)

  puts "Puma #{::Puma::Const::PUMA_VERSION} starting..."
  puts "* Min threads: #{min}, max threads: #{max}"
  puts "* Environment: #{ENV['RACK_ENV']}"
  puts "* Listening on tcp://#{options[:Host]}:#{options[:Port]}"

  server.add_tcp_listener options[:Host], options[:Port]
  server.min_threads = min
  server.max_threads = max
  yield server if block_given?

  begin
    server.run.join
  rescue Interrupt
    puts "* Gracefully stopping, waiting for requests to finish"
    server.stop(true)
    puts "* Goodbye!"
  end

end