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

Constant Summary collapse

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

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 48

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 52

def method_missing(meth, *args)
  return @actual_logger.__send__(meth, *args) if @actual_logger.respond_to?(meth)
  super
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 148

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 131

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)
  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 153

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 65

def debug(message = nil, &block)
  severity, message = filter(DEBUG, message)
  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 168

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 98

def error(message = nil, &block)
  severity, message = filter(ERROR, message)
  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 177

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 109

def fatal(message = nil, &block)
  severity, message = filter(FATAL, message)
  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 180

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 76

def info(message = nil, &block)
  severity, message = filter(INFO, message)
  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 171

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 158

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 163

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

#respond_to?(meth) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/right_support/log/filter_logger.rb', line 57

def respond_to?(meth)
  super(meth) || @actual_logger.respond_to?(meth)
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 87

def warn(message = nil, &block)
  severity, message = filter(WARN, message)
  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 174

def warn?; @actual_logger.warn?; end