Module: TransitionalLogger

Defined in:
lib/transitional_logger.rb

Overview

Author

Elon Flegenheimer

Copyright

Copyright © 2013 Elon Flegenheimer

License

The MIT License (MIT)

A singleton logger accessible from ALL objects. It is intended to be used to:

  • send logger data to stdout OR

  • log to a file while consuming stdout & stderr data as log input OR

  • destroy stdout, stderr, & log data OR

  • do one of the above until transitioned to another of the above

The logger can be altered just like a normal Logger:

logger.level = Logger::WARN

Example usage:

TransitionalLogger.stdout
logger.info 'this message goes through the logger to stdout'
puts 'this works like usual'

TransitionalLogger.file('/tmp/whatever.log')
Object.new.logger.info 'this message goes through the logger to the file above'
puts 'this message also goes through the logger above'

TransitionalLogger.blackhole
Object.new.logger.error 'this message disappears'
puts 'this message disappears too!'

Constant Summary collapse

VERSION = 
'1.0.0'

Class Method Summary collapse

Class Method Details

.blackhole ⇒ Object

Creates a logger that consumes stdout, stderr, and all logger messages.



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# File 'lib/transitional_logger.rb', line 59

def blackhole
  file('/dev/null')
end

.file(*args) ⇒ Object

Creates the specified logger that is accessible from all objects. stdout and stderr are redirected to this logger.

Parameters match Logger#new.

Raises:

  • (ArgumentError) 


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# File 'lib/transitional_logger.rb', line 47

def file(*args)
  raise ArgumentError, 'Logger#new params must be specified for #file' if args.size == 0
  reset if @streams
  @master_logger = infect_object(Logger.new(*args))

  @streams = [$stdout, $stderr, $stdin]
  $stdout = CommandeeredOut.new(@master_logger)
  $stderr = CommandeeredErr.new(@master_logger)
  @master_logger
end

.logger ⇒ Object

Logger accessor - otherwise accessible from any object



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# File 'lib/transitional_logger.rb', line 74

def logger
  @master_logger
end

.reset ⇒ Object

Reset the changes that this object has introduced



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# File 'lib/transitional_logger.rb', line 64

def reset
  @master_logger = nil
  Object.send :remove_method, :logger rescue nil
  if @streams
    $stdout, $stderr = @streams[0..1]
    @streams = nil
  end
end

.stdout ⇒ Object

Creates a logger that is accessible from all objects. The logger points to stdout. Stdout is otherwise unaffected.



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# File 'lib/transitional_logger.rb', line 38

def stdout
  reset if @streams
  @master_logger = infect_object(Logger.new($stdout))
end