Class: RightSupport::Log::FilterLogger

Inherits:
Logger
  • Object
show all
Defined in:
lib/right_support/log/filter_logger.rb

Overview

A logger than encapsulates an underlying Logger object and filters log entries before they are passed to the underlying Logger. Can be used to for various log- processing tasks such as filtering sensitive data or tagging log lines with a context marker.

FilterLogger implements method_missing and respond_to? and proxies unknown method calls to its underlying logger; this allows it to be used as a decorator.

Direct Known Subclasses

ExceptionLogger, StepLevelLogger

Constant Summary collapse

SEVERITY_TO_METHOD = 
{
    DEBUG => :debug,
    INFO  => :info,
    WARN  => :warn,
    ERROR => :error,
    FATAL => :fatal,
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(actual_logger) ⇒ FilterLogger

Initialize a new instance of this class.

Parameters

actual_logger(Logger)

The actual, underlying Logger object



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# File 'lib/right_support/log/filter_logger.rb', line 51

def initialize(actual_logger)
  @actual_logger = actual_logger
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(meth, *args) ⇒ Object 



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# File 'lib/right_support/log/filter_logger.rb', line 55

def method_missing(meth, *args)
  return @actual_logger.__send__(meth, *args) if @actual_logger.respond_to?(meth)
  super
end

Instance Attribute Details

#actual_logger ⇒ Logger (readonly)

Returns a reference to the underlying logger that receives filtered log calls.

Returns:

  • (Logger) —

    a reference to the underlying logger that receives filtered log calls



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# File 'lib/right_support/log/filter_logger.rb', line 44

def actual_logger
  @actual_logger
end

Instance Method Details

#<<(msg) ⇒ Object

Proxies to the encapsulated Logger object. See Logger#<< for info.



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# File 'lib/right_support/log/filter_logger.rb', line 157

def <<(msg)
  @actual_logger << msg
end

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

Add a log line, filtering the severity and message before calling through to the underlying logger’s #add method.

Parameters

severity(Integer)

one of the Logger severity constants

message(String)

the message to log, or nil

progname(String)

the program name, or nil

Block

If message == nil and a block is given, yields to the block in order to capture the log message. This matches the behavior of Logger, but ensures the severity and message are still filtered.

Return

the result of the underlying logger’s #add



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# File 'lib/right_support/log/filter_logger.rb', line 139

def add(severity, message = nil, progname = nil, &block)
  severity ||= UNKNOWN
  return true if severity < level

  if message.nil?
    if block_given?
      message = yield
    else
      message = progname
    end
  end

  severity, message = filter(severity, message_to_string(message))
  return true if severity.nil?
  return @actual_logger.add(severity, message) if message
end

#close ⇒ Object

Proxies to the encapsulated Logger object. See Logger#close for info.



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# File 'lib/right_support/log/filter_logger.rb', line 162

def close
  @actual_logger.close
end

#debug(message = nil, &block) ⇒ Object

Log a message, filtering the severity and/or message and dispatching to the corresponding severity-method of the underlying logger.

See #info for more information.

Raises:

  • (ArgumentError) 


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# File 'lib/right_support/log/filter_logger.rb', line 68

def debug(message = nil, &block)
  severity, message = filter(DEBUG, message_to_string(message))
  return true if severity.nil?
  meth = SEVERITY_TO_METHOD[severity]
  raise ArgumentError, "Filter emitted unknown severity #{severity.inspect}" unless meth
  @actual_logger.__send__(meth, message, &block)
end

#debug? ⇒ Boolean

Proxies to the encapsulated Logger object. See Logger#debug? for info.

Returns:

  • (Boolean) 


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# File 'lib/right_support/log/filter_logger.rb', line 177

def debug?; @actual_logger.debug?; end

#error(message = nil, &block) ⇒ Object

Log a message, filtering the severity and/or message and dispatching to the corresponding severity-method of the underlying logger.

See #info for more information.

Raises:

  • (ArgumentError) 


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# File 'lib/right_support/log/filter_logger.rb', line 104

def error(message = nil, &block)
  severity, message = filter(ERROR, message_to_string(message))
  return if severity.nil?
  meth = SEVERITY_TO_METHOD[severity]
  raise ArgumentError, "Filter emitted unknown severity #{severity.inspect}" unless meth
  @actual_logger.__send__(meth, message, &block)
end

#error? ⇒ Boolean

Proxies to the encapsulated Logger object. See Logger#error? for info.

Returns:

  • (Boolean) 


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# File 'lib/right_support/log/filter_logger.rb', line 186

def error?; @actual_logger.error?; end

#fatal(message = nil, &block) ⇒ Object

Log a message, filtering the severity and/or message and dispatching to the corresponding severity-method of the underlying logger.

See #info for more information.

Raises:

  • (ArgumentError) 


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# File 'lib/right_support/log/filter_logger.rb', line 116

def fatal(message = nil, &block)
  severity, message = filter(FATAL, message_to_string(message))
  return true if severity.nil?
  meth = SEVERITY_TO_METHOD[severity]
  raise ArgumentError, "Filter emitted unknown severity #{severity.inspect}" unless meth
  @actual_logger.__send__(meth, message, &block)
end

#fatal? ⇒ Boolean

Proxies to the encapsulated Logger object. See Logger#fatal? for info.

Returns:

  • (Boolean) 


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# File 'lib/right_support/log/filter_logger.rb', line 189

def fatal?; @actual_logger.fatal?; end

#info(message = nil, &block) ⇒ Object

Log a message, filtering the severity and/or message and dispatching to the corresponding severity-method of the underlying logger.

See #info for more information.

Raises:

  • (ArgumentError) 


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# File 'lib/right_support/log/filter_logger.rb', line 80

def info(message = nil, &block)
  severity, message = filter(INFO, message_to_string(message))
  return true if severity.nil?
  meth = SEVERITY_TO_METHOD[severity]
  raise ArgumentError, "Filter emitted unknown severity #{severity.inspect}" unless meth
  @actual_logger.__send__(meth, message, &block)
end

#info? ⇒ Boolean

Proxies to the encapsulated Logger object. See Logger#info? for info.

Returns:

  • (Boolean) 


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# File 'lib/right_support/log/filter_logger.rb', line 180

def info?; @actual_logger.info?; end

#level ⇒ Object

Proxies to the encapsulated Logger object. See Logger#level for info.



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# File 'lib/right_support/log/filter_logger.rb', line 167

def level
  @actual_logger.level
end

#level=(new_level) ⇒ Object

Proxies to the encapsulated Logger object. See Logger#level= for info.



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# File 'lib/right_support/log/filter_logger.rb', line 172

def level=(new_level)
  @actual_logger.level = new_level
end

#respond_to?(meth, *args) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/right_support/log/filter_logger.rb', line 60

def respond_to?(meth, *args)
  super(meth, *args) || @actual_logger.respond_to?(meth, *args)
end

#warn(message = nil, &block) ⇒ Object

Log a message, filtering the severity and/or message and dispatching to the corresponding severity-method of the underlying logger.

See #info for more information.

Raises:

  • (ArgumentError) 


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# File 'lib/right_support/log/filter_logger.rb', line 92

def warn(message = nil, &block)
  severity, message = filter(WARN, message_to_string(message))
  return true if severity.nil?
  meth = SEVERITY_TO_METHOD[severity]
  raise ArgumentError, "Filter emitted unknown severity #{severity.inspect}" unless meth
  @actual_logger.__send__(meth, message, &block)
end

#warn? ⇒ Boolean

Proxies to the encapsulated Logger object. See Logger#warn? for info.

Returns:

  • (Boolean) 


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# File 'lib/right_support/log/filter_logger.rb', line 183

def warn?; @actual_logger.warn?; end