Class: DaemonKit::AbstractLogger

Inherits:
Object
  • Object
show all
Defined in:
lib/daemon_kit/abstract_logger.rb

Overview

One of the key parts of succesful background processes is adequate logging. The AbstractLogger aims to simplify logging from inside daemon processes by providing additional useful information with each log line, including calling file name and line number and support for cleanly logging exceptions.

The logger can be accessed through #DaemonKit.logger.

AbstractLogger provides an interface that is fully compatible with the Logger class provided by Ruby’s Standard Library, and is extended with some additional conveniences.

The AbstractLogger supports different backends, by default it uses a Logger instance, but can by swapped out for a SysLogLogger logger as well.

Defined Under Namespace

Classes: Formatter

Class Attribute Summary collapse

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(log_path = nil) ⇒ AbstractLogger

Optional log path, defaults to DAEMON_ROOT/log/DAEMON_ENV.log



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# File 'lib/daemon_kit/abstract_logger.rb', line 41

def initialize( log_path = nil )
  if log_path.to_s == "syslog"
    @backend = :syslog
  else
    @logger_file = log_path || "#{DAEMON_ROOT}/log/#{DAEMON_ENV}.log"
    @backend = :logger
  end

  @copy_to_stdout = false
end

Class Attribute Details

.severities ⇒ Object (readonly)

Returns the value of attribute severities.



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# File 'lib/daemon_kit/abstract_logger.rb', line 35

def severities
  @severities
end

.silencer ⇒ Object

Returns the value of attribute silencer.



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# File 'lib/daemon_kit/abstract_logger.rb', line 36

def silencer
  @silencer
end

Instance Attribute Details

#copy_to_stdout ⇒ Object

Returns the value of attribute copy_to_stdout.



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# File 'lib/daemon_kit/abstract_logger.rb', line 21

def copy_to_stdout
  @copy_to_stdout
end

Instance Method Details

#<<(msg) ⇒ Object

Write unformatted message to logging device, mostly useful for Logger interface compatibility and debugging soap4r (possibly others)



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# File 'lib/daemon_kit/abstract_logger.rb', line 68

def <<( msg ) #:nodoc:
  self.logger.write( msg ) if self.logger && self.logger.respond_to?( :write )
end

#add(severity, message = nil, skip_caller = false, &block) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 126

def add( severity, message = nil, skip_caller = false, &block )
  message = yield if block_given?

  message = "#{called(caller)}: #{message}" unless skip_caller

  self.logger.add( self.class.severities[ severity ] ) { message }

  STDOUT.puts( message ) if self.copy_to_stdout
end

#clean_trace(trace) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 160

def clean_trace( trace )
  trace = trace.map { |l| l.gsub(DAEMON_ROOT, '') }
  trace = trace.reject { |l| l =~ /gems\/daemon[\-_]kit/ }
  trace
end

#close ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 166

def close
  case @backend
  when :logger
    self.logger.close
    @logger = nil
  end
end

#debug(msg = nil, &block) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 72

def debug( msg = nil, &block )
  add( :debug, msg, &block )
end

#debug? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/daemon_kit/abstract_logger.rb', line 76

def debug?
  self.level == :debug
end

#error(msg = nil, &block) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 96

def error( msg = nil, &block )
  add( :error, msg, &block )
end

#error? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/daemon_kit/abstract_logger.rb', line 100

def error?
  self.level == :error
end

#exception(e) ⇒ Object

Conveniently log an exception and the backtrace



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# File 'lib/daemon_kit/abstract_logger.rb', line 121

def exception( e )
  message = "EXCEPTION: #{e.message}: #{clean_trace( e.backtrace )}"
  self.add( :error, message, true )
end

#fatal(msg = nil, &block) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 104

def fatal( msg = nil, &block )
  add( :fatal, msg, &block )
end

#fatal? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/daemon_kit/abstract_logger.rb', line 108

def fatal?
  self.level == :fatal
end

#info(msg = nil, &block) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 80

def info( msg = nil, &block )
  add( :info, msg, &block )
end

#info? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/daemon_kit/abstract_logger.rb', line 84

def info?
  self.level == :info
end

#level ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 136

def level
  self.class.severities.invert[ @logger.level ]
end

#level=(level) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 140

def level=( level )
  level = ( Symbol === level ? self.class.severities[ level ] : level )
  self.logger.level = level
end

#logger ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 145

def logger
  @logger ||= create_logger
end

#logger=(logger) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 149

def logger=( logger )
  if logger.is_a?( Symbol )
    @backend = logger
    @logger.close rescue nil
    @logger = create_logger
  else
    @logger.close rescue nil
    @logger = logger
  end
end

#silence(temporary_level = :error) ⇒ Object

Silence the logger for the duration of the block.



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# File 'lib/daemon_kit/abstract_logger.rb', line 53

def silence( temporary_level = :error )
  if self.class.silencer
    begin
      old_level, self.level = self.level, temporary_level
      yield self
    ensure
      self.level = old_level
    end
  else
    yield self
  end
end

#unknown(msg = nil, &block) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 112

def unknown( msg = nil, &block )
  add( :unknown, msg, &block )
end

#unknown? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/daemon_kit/abstract_logger.rb', line 116

def unknown?
  self.level == :unknown
end

#warn(msg = nil, &block) ⇒ Object 



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# File 'lib/daemon_kit/abstract_logger.rb', line 88

def warn( msg = nil, &block )
  add( :warn, msg, &block )
end

#warn? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/daemon_kit/abstract_logger.rb', line 92

def warn?
  self.level == :warn
end