]> git.openstreetmap.org Git - rails.git/blobdiff - vendor/plugins/irs_process_scripts/lib/commands/process/spawner.rb
Add irs_process_scripts plugin to replace process control scripts used
[rails.git] / vendor / plugins / irs_process_scripts / lib / commands / process / spawner.rb
diff --git a/vendor/plugins/irs_process_scripts/lib/commands/process/spawner.rb b/vendor/plugins/irs_process_scripts/lib/commands/process/spawner.rb
new file mode 100644 (file)
index 0000000..8bf47ab
--- /dev/null
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+require 'active_support'
+require 'optparse'
+require 'socket'
+require 'fileutils'
+
+def daemonize #:nodoc:
+  exit if fork                   # Parent exits, child continues.
+  Process.setsid                 # Become session leader.
+  exit if fork                   # Zap session leader. See [1].
+  Dir.chdir "/"                  # Release old working directory.
+  File.umask 0000                # Ensure sensible umask. Adjust as needed.
+  STDIN.reopen "/dev/null"       # Free file descriptors and
+  STDOUT.reopen "/dev/null", "a" # point them somewhere sensible.
+  STDERR.reopen STDOUT           # STDOUT/ERR should better go to a logfile.
+end
+
+class Spawner
+  def self.record_pid(name = "#{OPTIONS[:process]}.spawner", id = Process.pid)
+    FileUtils.mkdir_p(OPTIONS[:pids])
+    File.open(File.expand_path(OPTIONS[:pids] + "/#{name}.pid"), "w+") { |f| f.write(id) }
+  end
+
+  def self.spawn_all
+    OPTIONS[:instances].times do |i|
+      port = OPTIONS[:port] + i
+      print "Checking if something is already running on #{OPTIONS[:address]}:#{port}..."
+
+      begin
+        srv = TCPServer.new(OPTIONS[:address], port)
+        srv.close
+        srv = nil
+
+        puts "NO"
+        puts "Starting dispatcher on port: #{OPTIONS[:address]}:#{port}"
+
+        FileUtils.mkdir_p(OPTIONS[:pids])
+        spawn(port)
+      rescue
+        puts "YES"
+      end
+    end
+  end
+end
+
+class FcgiSpawner < Spawner
+  def self.spawn(port)
+    cmd = "#{OPTIONS[:spawner]} -f #{OPTIONS[:dispatcher]} -p #{port} -P #{OPTIONS[:pids]}/#{OPTIONS[:process]}.#{port}.pid"
+    cmd << " -a #{OPTIONS[:address]}" if can_bind_to_custom_address?
+    system(cmd)
+  end
+
+  def self.can_bind_to_custom_address?
+    @@can_bind_to_custom_address ||= /^\s-a\s/.match `#{OPTIONS[:spawner]} -h`
+  end
+end
+
+class MongrelSpawner < Spawner
+  def self.spawn(port)
+    cmd =
+      "mongrel_rails start -d " +
+      "-a #{OPTIONS[:address]} " +
+      "-p #{port} " +
+      "-P #{OPTIONS[:pids]}/#{OPTIONS[:process]}.#{port}.pid " +
+      "-e #{OPTIONS[:environment]} " +
+      "-c #{OPTIONS[:rails_root]} " +
+      "-l #{OPTIONS[:rails_root]}/log/mongrel.log"
+
+    # Add prefix functionality to spawner's call to mongrel_rails
+    # Digging through mongrel's project subversion server, the earliest
+    # Tag that has prefix implemented in the bin/mongrel_rails file
+    # is 0.3.15 which also happens to be the earliest tag listed.
+    # References: http://mongrel.rubyforge.org/svn/tags
+    if Mongrel::Const::MONGREL_VERSION.to_f >=0.3 && !OPTIONS[:prefix].nil?
+      cmd = cmd + " --prefix #{OPTIONS[:prefix]}"
+    end
+    system(cmd)
+  end
+  
+  def self.can_bind_to_custom_address?
+    true
+  end
+end
+
+
+begin
+  require_library_or_gem 'fcgi'
+rescue Exception
+  # FCGI not available
+end
+
+begin
+  require_library_or_gem 'mongrel'
+rescue Exception
+  # Mongrel not available
+end
+
+server = case ARGV.first
+  when "fcgi", "mongrel"
+    ARGV.shift
+  else
+    if defined?(Mongrel)
+      "mongrel"
+    elsif RUBY_PLATFORM !~ /(:?mswin|mingw)/ && !silence_stderr { `spawn-fcgi -version` }.blank? && defined?(FCGI)
+      "fcgi"
+    end
+end
+
+case server
+  when "fcgi"
+    puts "=> Starting FCGI dispatchers"
+    spawner_class = FcgiSpawner
+  when "mongrel"
+    puts "=> Starting mongrel dispatchers"
+    spawner_class = MongrelSpawner
+  else
+    puts "Neither FCGI (spawn-fcgi) nor Mongrel was installed and available!"
+    exit(0)
+end
+
+
+
+OPTIONS = {
+  :environment => "production",
+  :spawner     => '/usr/bin/env spawn-fcgi',
+  :dispatcher  => File.expand_path(RELATIVE_RAILS_ROOT + '/public/dispatch.fcgi'),
+  :pids        => File.expand_path(RELATIVE_RAILS_ROOT + "/tmp/pids"),
+  :rails_root  => File.expand_path(RELATIVE_RAILS_ROOT),
+  :process     => "dispatch",
+  :port        => 8000,
+  :address     => '0.0.0.0',
+  :instances   => 3,
+  :repeat      => nil,
+  :prefix      => nil
+}
+
+ARGV.options do |opts|
+  opts.banner = "Usage: spawner [platform] [options]"
+
+  opts.separator ""
+
+  opts.on <<-EOF
+  Description:
+    The spawner is a wrapper for spawn-fcgi and mongrel that makes it
+    easier to start multiple processes running the Rails dispatcher. The
+    spawn-fcgi command is included with the lighttpd web server, but can
+    be used with both Apache and lighttpd (and any other web server
+    supporting externally managed FCGI processes). Mongrel automatically
+    ships with with mongrel_rails for starting dispatchers.
+
+    The first choice you need to make is whether to spawn the Rails
+    dispatchers as FCGI or Mongrel. By default, this spawner will prefer
+    Mongrel, so if that's installed, and no platform choice is made,
+    Mongrel is used.
+
+    Then decide a starting port (default is 8000) and the number of FCGI
+    process instances you'd like to run. So if you pick 9100 and 3
+    instances, you'll start processes on 9100, 9101, and 9102.
+
+    By setting the repeat option, you get a protection loop, which will
+    attempt to restart any FCGI processes that might have been exited or
+    outright crashed.
+
+    You can select bind address for started processes. By default these
+    listen on every interface. For single machine installations you would
+    probably want to use 127.0.0.1, hiding them form the outside world.
+
+     Examples:
+       spawner               # starts instances on 8000, 8001, and 8002
+                             # using Mongrel if available.
+       spawner fcgi          # starts instances on 8000, 8001, and 8002
+                             # using FCGI.
+       spawner mongrel -i 5  # starts instances on 8000, 8001, 8002,
+                             # 8003, and 8004 using Mongrel.
+       spawner -p 9100 -i 10 # starts 10 instances counting from 9100 to
+                             # 9109 using Mongrel if available.
+       spawner -p 9100 -r 5  # starts 3 instances counting from 9100 to
+                             # 9102 and attempts start them every 5
+                             # seconds.
+       spawner -a 127.0.0.1  # starts 3 instances binding to localhost
+  EOF
+
+  opts.on("  Options:")
+
+  opts.on("-p", "--port=number",      Integer, "Starting port number (default: #{OPTIONS[:port]})")                { |v| OPTIONS[:port] = v }
+
+  if spawner_class.can_bind_to_custom_address?
+    opts.on("-a", "--address=ip",     String,  "Bind to IP address (default: #{OPTIONS[:address]})")                { |v| OPTIONS[:address] = v }
+  end
+
+  opts.on("-p", "--port=number",      Integer, "Starting port number (default: #{OPTIONS[:port]})")                { |v| OPTIONS[:port] = v }
+  opts.on("-i", "--instances=number", Integer, "Number of instances (default: #{OPTIONS[:instances]})")            { |v| OPTIONS[:instances] = v }
+  opts.on("-r", "--repeat=seconds",   Integer, "Repeat spawn attempts every n seconds (default: off)")             { |v| OPTIONS[:repeat] = v }
+  opts.on("-e", "--environment=name", String,  "test|development|production (default: #{OPTIONS[:environment]})")  { |v| OPTIONS[:environment] = v }
+  opts.on("-P", "--prefix=path",      String,  "URL prefix for Rails app. [Used only with Mongrel > v0.3.15]: (default: #{OPTIONS[:prefix]})")         { |v| OPTIONS[:prefix] = v }
+  opts.on("-n", "--process=name",     String,  "default: #{OPTIONS[:process]}")                                    { |v| OPTIONS[:process] = v }
+  opts.on("-s", "--spawner=path",     String,  "default: #{OPTIONS[:spawner]}")                                    { |v| OPTIONS[:spawner] = v }
+  opts.on("-d", "--dispatcher=path",  String,  "default: #{OPTIONS[:dispatcher]}") { |dispatcher| OPTIONS[:dispatcher] = File.expand_path(dispatcher) }
+
+  opts.separator ""
+
+  opts.on("-h", "--help", "Show this help message.") { puts opts; exit }
+
+  opts.parse!
+end
+
+ENV["RAILS_ENV"] = OPTIONS[:environment]
+
+if OPTIONS[:repeat]
+  daemonize
+  trap("TERM") { exit }
+  spawner_class.record_pid
+
+  loop do
+    spawner_class.spawn_all
+    sleep(OPTIONS[:repeat])
+  end
+else
+  spawner_class.spawn_all
+end