Class: Puppet::Daemon Private

Inherits:
Object show all
Defined in:
lib/puppet/daemon.rb

Overview

This class is part of a private API. You should avoid using this class if possible, as it may be removed or be changed in the future.

Run periodic actions and a network server in a daemonized process.

A Daemon has 3 parts:

* config reparse
* (optional) an agent that responds to #run
* (optional) a server that response to #stop, #start, and #wait_for_shutdown

The config reparse will occur periodically based on Settings. The server will be started and is expected to manage its own run loop (and so not block the start call). The server will, however, still be waited for by using the #wait_for_shutdown method. The agent is run periodically and a time interval based on Settings. The config reparse will update this time interval when needed.

The Daemon is also responsible for signal handling, starting, stopping, running the agent on demand, and reloading the entire process. It ensures that only one Daemon is running by using a lockfile.

Constant Summary collapse

SIGNAL_CHECK_INTERVAL =

This constant is part of a private API. You should avoid using this constant if possible, as it may be removed or be changed in the future. 

5

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(pidfile, scheduler = Puppet::Scheduler::Scheduler.new()) ⇒ Daemon

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a new instance of Daemon.



29
30
31
32
33
 
# File 'lib/puppet/daemon.rb', line 29

def initialize(pidfile, scheduler = Puppet::Scheduler::Scheduler.new())
  @scheduler = scheduler
  @pidfile = pidfile
  @signals = []
end

Instance Attribute Details

#agent ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



26
27
28
 
# File 'lib/puppet/daemon.rb', line 26

def agent
  @agent
end

#argv ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



26
27
28
 
# File 'lib/puppet/daemon.rb', line 26

def argv
  @argv
end

#server ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



26
27
28
 
# File 'lib/puppet/daemon.rb', line 26

def server
  @server
end

#signals ⇒ Object (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



27
28
29
 
# File 'lib/puppet/daemon.rb', line 27

def signals
  @signals
end

Class Method Details

.close_streams ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Close stdin/stdout/stderr so that we can finish our transition into ‘daemon’ mode.

Returns:

  • nil



59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
 
# File 'lib/puppet/daemon.rb', line 59

def self.close_streams()
  Puppet.debug("Closing streams for daemon mode")
  begin
    $stdin.reopen "/dev/null"
    $stdout.reopen "/dev/null", "a"
    $stderr.reopen $stdout
    Puppet::Util::Log.reopen
    Puppet.debug("Finished closing streams for daemon mode")
  rescue => detail
    Puppet.err "Could not start #{Puppet.run_mode.name}: #{detail}"
    Puppet::Util::replace_file("/tmp/daemonout", 0644) do |f|
      f.puts "Could not start #{Puppet.run_mode.name}: #{detail}"
    end
    exit(12)
  end
end

Instance Method Details

#close_streams ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Convenience signature for calling Puppet::Daemon.close_streams



77
78
79
 
# File 'lib/puppet/daemon.rb', line 77

def close_streams()
  Puppet::Daemon.close_streams
end

#daemonize ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Put the daemon into the background.



40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
 
# File 'lib/puppet/daemon.rb', line 40

def daemonize
  if pid = fork
    Process.detach(pid)
    exit(0)
  end

  create_pidfile

  # Get rid of console logging
  Puppet::Util::Log.close(:console)

  Process.setsid
  Dir.chdir("/")

  close_streams
end

#daemonname ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



35
36
37
 
# File 'lib/puppet/daemon.rb', line 35

def daemonname
  Puppet.run_mode.name
end

#reexec ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Raises:



81
82
83
84
85
86
87
 
# File 'lib/puppet/daemon.rb', line 81

def reexec
  raise Puppet::DevError, "Cannot reexec unless ARGV arguments are set" unless argv
  command = $0 + " " + argv.join(" ")
  Puppet.notice "Restarting with '#{command}'"
  stop(:exit => false)
  exec(command)
end

#reload ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



89
90
91
92
93
94
 
# File 'lib/puppet/daemon.rb', line 89

def reload
  return unless agent
  agent.run({:splay => false})
rescue Puppet::LockError
  Puppet.notice "Not triggering already-running agent"
end

#reopen_logs ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



101
102
103
 
# File 'lib/puppet/daemon.rb', line 101

def reopen_logs
  Puppet::Util::Log.reopen
end

#restart ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



96
97
98
99
 
# File 'lib/puppet/daemon.rb', line 96

def restart
  Puppet::Application.restart!
  reexec unless agent and agent.running?
end

#set_signal_traps ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Trap a couple of the main signals. This should probably be handled in a way that anyone else can register callbacks for traps, but, eh.



107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
 
# File 'lib/puppet/daemon.rb', line 107

def set_signal_traps
  [:INT, :TERM].each do |signal|
    Signal.trap(signal) do
      Puppet.notice "Caught #{signal}; exiting"
      stop
    end
  end

  # extended signals not supported under windows
  if !Puppet.features.microsoft_windows?
    signals = {:HUP => :restart, :USR1 => :reload, :USR2 => :reopen_logs }
    signals.each do |signal, method|
      Signal.trap(signal) do
        Puppet.notice "Caught #{signal}; storing #{method}"
        @signals << method
      end
    end
  end
end

#start ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Raises:



140
141
142
143
144
145
146
147
148
149
150
151
152
 
# File 'lib/puppet/daemon.rb', line 140

def start
  create_pidfile

  raise Puppet::DevError, "Daemons must have an agent, server, or both" unless agent or server

  # Start the listening server, if required.
  server.start if server

  # Finally, loop forever running events - or, at least, until we exit.
  run_event_loop

  server.wait_for_shutdown if server
end

#stop(args = {:exit => true}) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Stop everything



128
129
130
131
132
133
134
135
136
137
138
 
# File 'lib/puppet/daemon.rb', line 128

def stop(args = {:exit => true})
  Puppet::Application.stop!

  server.stop if server

  remove_pidfile

  Puppet::Util::Log.close_all

  exit if args[:exit]
end