Harbor Documentation

Harbor::Daemon

Constants

  • START_CONTEXT
  • DEFAULT_SLEEP_SECONDS

Attributes

  • logger [RW] (Not documented)
  • worker [R] (Not documented)
  • options [R] (Not documented)

Public Class Methods

new(worker, log_file, seconds_between_runs = DEFAULT_SLEEP_SECONDS) 

      # File lib/harbor/daemon.rb, line 16
16:     def initialize(worker, log_file, seconds_between_runs = DEFAULT_SLEEP_SECONDS)
17:       @worker = worker
18: 
19:       # The template may include the tag %PID to be replaced with
20:       # the PID of the forked worker process.  Don't use @log_file
21:       # directly, use self.log_file
22:       @log_file_template = log_file
23:       
24:       @seconds_between_runs = seconds_between_runs
25:     end

Public Instance Methods

cleanup!() 

      # File lib/harbor/daemon.rb, line 94
94:     def cleanup!
95:       worker.cleanup! if worker.respond_to?(:cleanup!)
96:     end

detach() 

      # File lib/harbor/daemon.rb, line 35
35:     def detach
36:       srand
37:       fork and exit
38:       Process.setsid # detach -- we want to be able to close our shell!
39: 
40:       unless self.log_file.is_a?(::File)
41:         log_directory = ::File.dirname(self.log_file)
42:         ::File.mkdir_p(log_directory) unless ::File.directory?(log_directory)
43:       end
44: 
45:       redirect_io(@log_file)
46:     end

log_file() 

      # File lib/harbor/daemon.rb, line 27
27:     def log_file
28:       @log_file ||= if @log_file_template.is_a?(::File)
29:         @log_file_template
30:       else
31:         @log_file_template.gsub('%PID', Process.pid.to_s)
32:       end
33:     end

run() 

      # File lib/harbor/daemon.rb, line 48
48:     def run
49:       @restart = false
50:       @alive = true
51:     
52:       # graceful restart
53:       trap(:HUP) do
54:         logger.info "Restarting gracefully." if logger
55:         @restart = true
56:         @alive = nil
57:         @worker.alive = nil
58:       end
59:     
60:       # graceful shutdown
61:       trap(:QUIT) do
62:         logger.info "Shutting down gracefully." if logger
63:         @alive = nil
64:         @worker.alive = nil
65:       end
66:     
67:       # quick exit
68:       [:TERM, :INT].each do |sig|
69:         trap(sig) do
70:           logger.info "Shutting down NOW" if logger
71:           cleanup!
72:     
73:           exit!(0)
74:         end
75:       end
76:       
77:       begin
78:         @worker.run
79:         sleep(@seconds_between_runs) if @alive
80:       end while @alive
81:         
82:       if @restart
83:         logger.info "Starting new daemon..."
84:         fork do
85:           Dir.chdir(START_CONTEXT[:cwd])
86:           exec(START_CONTEXT[:cmd], *START_CONTEXT[:argv])
87:         end
88:       end
89: 
90:       logger.info "Shutting down..." if logger
91:       cleanup!
92:     end

Private Instance Methods

redirect_io(file = nil) 

       # File lib/harbor/daemon.rb, line 100
100:     def redirect_io(file = nil)
101:       STDIN.reopen "/dev/null"
102:       STDOUT.reopen file || "/dev/null"
103:       STDOUT.sync = true
104: 
105:       STDERR.reopen STDOUT
106:       STDERR.sync = true
107:     end