Class: RExec::Daemon::Base

Inherits:
Object
  • Object
show all
Defined in:
lib/rexec/daemon/base.rb

Overview

This class is the base daemon class. If you are writing a daemon, you should inherit from this class.

Constant Summary collapse

@@var_directory = 
nil
@@log_directory = 
nil
@@pid_directory = 
nil

Class Method Summary collapse

Class Method Details

.crashed? ⇒ Boolean

Check the last few lines of the log file to find out if the daemon crashed.

Returns:

  • (Boolean) 


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# File 'lib/rexec/daemon/base.rb', line 95

def self.crashed?
  File.open(err_fn, "r") do |fp|
    fp.seek_end
    
    count = 2
    fp.reverse_each_line do |line|
      return true if line.match("=== Daemon Crashed")
      
      count -= 1
      
      break if count == 0
    end
  end
  
  return false
end

.daemon_name ⇒ Object

Return the name of the daemon



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# File 'lib/rexec/daemon/base.rb', line 29

def self.daemon_name
  return name.gsub(/[^a-zA-Z0-9]+/, '-')
end

.daemonize ⇒ Object

Corresponds to controller method of the same name



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# File 'lib/rexec/daemon/base.rb', line 113

def self.daemonize
  Controller.daemonize(self)
end

.err_fn ⇒ Object

Standard log file for errors



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# File 'lib/rexec/daemon/base.rb', line 49

def self.err_fn
  File.join(log_directory, "stderr.log")
end

.log_directory ⇒ Object

Return the directory to store log files in



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# File 'lib/rexec/daemon/base.rb', line 44

def self.log_directory
  @@log_directory || File.join(var_directory, "log", daemon_name)
end

.log_fn ⇒ Object

Standard log file for normal output



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# File 'lib/rexec/daemon/base.rb', line 54

def self.log_fn
  File.join(log_directory, "stdout.log")
end

.mark_err_log ⇒ Object

Mark the error log



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# File 'lib/rexec/daemon/base.rb', line 69

def self.mark_err_log
  fp = File.open(err_fn, "a")
  fp.puts "=== Error Log Opened @ #{Time.now.to_s} ==="
  fp.close
end

.pid_directory ⇒ Object

Standard location of pid file



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# File 'lib/rexec/daemon/base.rb', line 59

def self.pid_directory
  @@pid_directory || File.join(var_directory, "run", daemon_name)
end

.pid_fn ⇒ Object

Standard pid file



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# File 'lib/rexec/daemon/base.rb', line 64

def self.pid_fn
  File.join(pid_directory, "#{daemon_name}.pid")
end

.prefork ⇒ Object

The main function to setup any environment required by the daemon



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# File 'lib/rexec/daemon/base.rb', line 133

def self.prefork
  @@var_directory = File.expand_path(@@var_directory) if @@var_directory
  @@log_directory = File.expand_path(@@log_directory) if @@log_directory
  @@pid_directory = File.expand_path(@@pid_directory) if @@pid_directory
  
  FileUtils.mkdir_p(log_directory)
  FileUtils.mkdir_p(pid_directory)
end

.run ⇒ Object

The main function to start the daemon



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# File 'lib/rexec/daemon/base.rb', line 143

def self.run
end

.shutdown ⇒ Object

The main function to stop the daemon



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# File 'lib/rexec/daemon/base.rb', line 147

def self.shutdown
end

.start ⇒ Object

Corresponds to controller method of the same name



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# File 'lib/rexec/daemon/base.rb', line 118

def self.start
  Controller.start(self)
end

.status ⇒ Object

Corresponds to controller method of the same name



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# File 'lib/rexec/daemon/base.rb', line 128

def self.status
  Controller.status(self)
end

.stop ⇒ Object

Corresponds to controller method of the same name



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# File 'lib/rexec/daemon/base.rb', line 123

def self.stop
  Controller.stop(self)
end

.tail_err_log(outp) ⇒ Object

Prints some information relating to daemon startup problems



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# File 'lib/rexec/daemon/base.rb', line 76

def self.tail_err_log(outp)
  lines = []
  
  File.open(err_fn, "r") do |fp|
    fp.seek_end

    fp.reverse_each_line do |line|
      lines << line
      break if line.match("=== Error Log") || line.match("=== Daemon Exception Backtrace")
    end
  end
  
  lines.reverse_each do |line|
    outp.puts line
  end
end

.var_directory ⇒ Object

Base directory for daemon log files / run files



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# File 'lib/rexec/daemon/base.rb', line 34

def self.var_directory
  @@var_directory || File.join("", "var")
end

.working_directory ⇒ Object

The directory the daemon will run in (Dir.chdir)



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# File 'lib/rexec/daemon/base.rb', line 39

def self.working_directory
  var_directory
end