Daemons::Monitor

    # File lib/daemons/monitor.rb, line 8
 8:     def self.find(dir, app_name)
 9:       pid = PidFile.find_files(dir, app_name, false)[0]
10:       
11:       if pid
12:         pid = PidFile.existing(pid)
13:         
14:         unless PidFile.running?(pid.pid)
15:           begin; pid.cleanup; rescue ::Exception; end
16:           return
17:         end
18:         
19:         monitor = self.allocate
20:       
21:         monitor.instance_variable_set(:@pid, pid)
22:         
23:         return monitor
24:       end
25:       
26:       return nil
27:     end

    # File lib/daemons/monitor.rb, line 30
30:     def initialize(an_app)
31:       @app = an_app
32:       @app_name = an_app.group.app_name + '_monitor'
33:       
34:       if an_app.pidfile_dir
35:         @pid = PidFile.new(an_app.pidfile_dir, @app_name, false)
36:       else
37:         @pid = PidMem.new
38:       end
39:     end

     # File lib/daemons/monitor.rb, line 107
107:     def start(applications)
108:       return if applications.empty?
109:       
110:       if @pid.kind_of?(PidFile)
111:         start_with_pidfile(applications)
112:       else
113:         start_without_pidfile(applications)
114:       end
115:     end

     # File lib/daemons/monitor.rb, line 118
118:     def stop
119:       begin
120:         pid = @pid.pid
121:         Process.kill(Application::SIGNAL, pid)
122:                 Timeout::timeout(5) {      
123:           while Pid.running?(pid)
124:             sleep(0.1)
125:           end
126:         }
127:       rescue ::Exception => e
128:         puts "#{e} #{pid}"
129:         puts "deleting pid-file."
130:       end
131:       
132:       # We try to remove the pid-files by ourselves, in case the application
133:       # didn't clean it up.
134:       begin; @pid.cleanup; rescue ::Exception; end
135:     end

    # File lib/daemons/monitor.rb, line 63
63:     def start_with_pidfile(applications)
64:       fork do
65:         Daemonize.daemonize(nil, @app_name)
66:         
67:         begin  
68:           @pid.pid = Process.pid
69:           
70:   #         at_exit {
71:   # begin; @pid.cleanup; rescue ::Exception; end
72:   #         }
73:           
74:           # This part is needed to remove the pid-file if the application is killed by 
75:           # daemons or manually by the user.
76:           # Note that the applications is not supposed to overwrite the signal handler for
77:           # 'TERM'.
78:           #
79:   #         trap('TERM') {
80:   # begin; @pid.cleanup; rescue ::Exception; end
81:   #           exit
82:   #         }
83:           
84:           watch(applications)
85:         rescue ::Exception => e
86:           begin
87:             File.open(@app.logfile, 'a') {|f|
88:               f.puts Time.now
89:               f.puts e
90:               f.puts e.backtrace.inspect
91:             }
92:           ensure 
93:             begin; @pid.cleanup; rescue ::Exception; end
94:             exit!
95:           end
96:         end
97:       end
98:     end

     # File lib/daemons/monitor.rb, line 101
101:     def start_without_pidfile(applications)
102:       Thread.new { watch(applications) }
103:     end

    # File lib/daemons/monitor.rb, line 41
41:     def watch(applications)
42:       sleep(30)
43:       
44:       loop do
45:         applications.each {|a|
46:           sleep(10)
47:           
48:           unless a.running?
49:             a.zap!
50:             
51:             Process.detach(fork { a.start })
52:             
53:             sleep(10)
54:           end
55:         }
56:         
57:         sleep(30)
58:       end
59:     end