Class: WatchmonkeyCli::Checker

Inherits:
Object
  • Object
show all
Includes:
Helper
Defined in:
lib/watchmonkey_cli/checker.rb

Defined Under Namespace

Modules: AppHelper Classes: Result

Constant Summary

Constants included from Helper

Helper::BYTE_UNITS

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Helper

#human_filesize, #human_number, #human_seconds

Constructor Details

#initialize(app) ⇒ Checker

Returns a new instance of Checker.



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# File 'lib/watchmonkey_cli/checker.rb', line 112

def initialize app
  @app = app
  send(:init) if respond_to?(:init)
end

Instance Attribute Details

#app ⇒ Object (readonly)

Returns the value of attribute app.



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# File 'lib/watchmonkey_cli/checker.rb', line 110

def app
  @app
end

Class Method Details

.checker_name ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 12

def self.checker_name
  @checker_name || self.name
end

.checker_name=(name) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 16

def self.checker_name= name
  @checker_name = name
end

.descendants ⇒ Object

Descendant tracking for inherited classes.



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# File 'lib/watchmonkey_cli/checker.rb', line 4

def self.descendants
  @descendants ||= []
end

.inherited(descendant) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 8

def self.inherited(descendant)
  descendants << descendant
end

Instance Method Details

#_tolog(msg, meth = :log) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 139

def _tolog msg, meth = :log
  return unless app.opts[:logfile]
  app.logger.public_send(meth, msg)
end

#check!(*a) ⇒ Object

Raises:

  • (NotImplementedError) 


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# File 'lib/watchmonkey_cli/checker.rb', line 228

def check! *a
  # required, see #enqueue
  raise NotImplementedError, "a checker (#{self.class.name}) must implement `#check!' method!"
end

#debug(msg, robj = nil) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 124

def debug msg, robj = nil
  app.fire(:on_debug, msg, robj)
  app.fire(:on_message, msg, robj)
  return if app.opts[:quiet] || app.opts[:silent]
  _tolog(msg, :debug)
  app.puts app.c(msg, :black)
end

#enqueue(*args) ⇒ Object

Raises:

  • (NotImplementedError) 


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# File 'lib/watchmonkey_cli/checker.rb', line 221

def enqueue *args
  # Called by configuration defining a check with all the arguments.
  #   e.g. www_availability :my_host, foo: "bar" => args = [:my_host, {foo: "bar"}]
  # Should invoke `app.enqueue` which will by default call `#check!` method with given arguments.
  raise NotImplementedError, "a checker (#{self.class.name}) must implement `#enqueue' method!"
end

#error(msg, robj = nil) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 132

def error msg, robj = nil
  app.fire(:on_error, msg, robj)
  app.fire(:on_message, msg, robj)
  _tolog(msg, :error)
  app.sync { app.error(msg) }
end

#info(msg, robj = nil) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 117

def info msg, robj = nil
  app.fire(:on_info, msg, robj)
  return if app.opts[:quiet]
  _tolog(msg, :info)
  app.puts app.c(msg, :blue)
end

#init ⇒ Object

API =



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# File 'lib/watchmonkey_cli/checker.rb', line 203

def init
  # hook method (called when checker is being initialized)
end

#local ⇒ Object

def to_s

string = "#<#{self.class.name}:#{self.object_id} "
fields = self.class.inspector_fields.map{|field| "#{field}: #{self.send(field)}"}
string << fields.join(", ") << ">"

end



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# File 'lib/watchmonkey_cli/checker.rb', line 156

def local
  @app.fetch_connection(:loopback, :local)
end

#rsafe(resultobj, &block) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 178

def rsafe resultobj, &block
  tries = 0
  begin
    tries += 1
    block.call
  rescue StandardError => e
    unless tries > 3
      resultobj.sync do
        resultobj.error! "retry #{tries} reason is `#{e.class}: #{e.message}'"
        e.backtrace.each{|l| resultobj.debug "\t\t#{l}" }
        resultobj.dump!
      end
      sleep 1
      retry
    end
    resultobj.error! "#{descriptor}retries exceeded"
    resultobj.dump!
  end
end

#safe(descriptor = nil, &block) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 160

def safe descriptor = nil, &block
  tries = 0
  begin
    tries += 1
    block.call
  rescue StandardError => e
    unless tries > 3
      app.sync do
        error "#{descriptor}retry #{tries} reason is `#{e.class}: #{e.message}'"
        e.backtrace.each{|l| debug "\t\t#{l}" }
      end
      sleep 1
      retry
    end
    error "#{descriptor}retries exceeded"
  end
end

#spawn_sub(which, *args) ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 144

def spawn_sub which, *args
  if sec = app.checkers[which.to_s]
    sec.enqueue(*args)
  end
end

#start ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 207

def start
  # hook method (called after all checkers were initialized and configs + hosts are loaded)
  # can/should be used for starting connections, etc.
end

#stop ⇒ Object 



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# File 'lib/watchmonkey_cli/checker.rb', line 212

def stop
  # hook method (called on application shutdown)
  # connections should be closed here

  # DO NOT CLOSE CONNECTIONS HANDLED BY THE APP!
  # Keep in mind that the checkers run concurrently
  # and therefore shared resources might still be in use
end