Class: God::EventHandler

Inherits:
Object
  • Object
show all
Defined in:
lib/god/event_handler.rb

Constant Summary collapse

@@actions = 
{}
@@handler = 
nil
@@loaded = 
false

Class Method Summary collapse

Class Method Details

.call(pid, event, extra_data = {}) ⇒ Object 



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# File 'lib/god/event_handler.rb', line 50

def self.call(pid, event, extra_data = {})
  @@actions[pid][event].call(extra_data) if watching_pid?(pid) && @@actions[pid][event]
end

.deregister(pid, event) ⇒ Object 



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# File 'lib/god/event_handler.rb', line 41

def self.deregister(pid, event)
  if watching_pid? pid
    running = ::Process.kill(0, pid.to_i) rescue false
    @@actions[pid].delete(event)
    @@handler.register_process(pid, @@actions[pid].keys) if running
    @@actions.delete(pid) if @@actions[pid].empty?
  end
end

.event_system ⇒ Object 



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# File 'lib/god/event_handler.rb', line 11

def self.event_system
  @@handler::EVENT_SYSTEM
end

.load ⇒ Object 



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# File 'lib/god/event_handler.rb', line 15

def self.load
  begin
    case RUBY_PLATFORM
    when /darwin/i, /bsd/i
      require 'god/event_handlers/kqueue_handler'
      @@handler = KQueueHandler
    when /linux/i
      require 'god/event_handlers/netlink_handler'
      @@handler = NetlinkHandler
    else
      raise NotImplementedError, "Platform not supported for EventHandler"
    end
    @@loaded = true
  rescue Exception
    require 'god/event_handlers/dummy_handler'
    @@handler = DummyHandler
    @@loaded = false
  end
end

.loaded? ⇒ Boolean 



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# File 'lib/god/event_handler.rb', line 7

def self.loaded?
  @@loaded
end

.operational? ⇒ Boolean 



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# File 'lib/god/event_handler.rb', line 75

def self.operational?
  com = [false]
  
  Thread.new do
    begin
      event_system = God::EventHandler.event_system
      
      pid = fork do
        loop { sleep(1) }
      end
      
      self.register(pid, :proc_exit) do
        com[0] = true
      end
      
      ::Process.kill('KILL', pid)
      ::Process.waitpid(pid)
      
      sleep(0.1)
      
      self.deregister(pid, :proc_exit) rescue nil
    rescue => e
      puts e.message
      puts e.backtrace.join("\n")
    end
  end.join
  
  sleep(0.1)
  
  com.first
end

.register(pid, event, &block) ⇒ Object 



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# File 'lib/god/event_handler.rb', line 35

def self.register(pid, event, &block)
  @@actions[pid] ||= {}
  @@actions[pid][event] = block
  @@handler.register_process(pid, @@actions[pid].keys)
end

.start ⇒ Object 



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# File 'lib/god/event_handler.rb', line 58

def self.start
  Thread.new do
    loop do
      begin
        @@handler.handle_events
      rescue Exception => e
        message = format("Unhandled exception (%s): %s\n%s",
                         e.class, e.message, e.backtrace.join("\n"))
        applog(nil, :fatal, message)
      end
    end
  end
  
  # do a real test to make sure events are working properly
  @@loaded = self.operational?
end

.watching_pid?(pid) ⇒ Boolean 



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# File 'lib/god/event_handler.rb', line 54

def self.watching_pid?(pid)
  @@actions[pid]
end