Class: Lumberjack::Logger

Inherits:
Object
  • Object
show all
Includes:
Severity
Defined in:
lib/lumberjack/logger.rb

Overview

Logger is a thread safe logging object. It has a compatible API with the Ruby standard library Logger class, the Log4r gem, and ActiveSupport::BufferedLogger.

Example

logger = Lumberjack::Logger.new
logger.info("Starting processing")
logger.debug("Processing options #{options.inspect}")
logger.fatal("OMG the application is on fire!")

Log entries are written to a logging Device if their severity meets or exceeds the log level.

Devices may use buffers internally and the log entries are not guaranteed to be written until you call the flush method. Sometimes this can result in problems when trying to track down extraordinarily long running sections of code since it is likely that none of the messages logged before the long running code will appear in the log until the entire process finishes. You can set the :flush_seconds option on the constructor to force the device to be flushed periodically. This will create a new monitoring thread, but its use is highly recommended.

Each log entry records the log message and severity along with the time it was logged, the program name, process id, and unit of work id. The message will be converted to a string, but otherwise, it is up to the device how these values are recorded. Messages are converted to strings using a Formatter associated with the logger.

Constant Summary

Constants included from Severity

Severity::DEBUG, Severity::ERROR, Severity::FATAL, Severity::INFO, Severity::SEVERITY_LABELS, Severity::UNKNOWN, Severity::WARN

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Severity

coerce, label_to_level, level_to_label

Constructor Details

#initialize(device = $stdout, options = {}) ⇒ Logger

Create a new logger to log to a Device.

The device argument can be in any one of several formats.

If it is a Device object, that object will be used. If it has a write method, it will be wrapped in a Device::Writer class. If it is :null, it will be a Null device that won’t record any output. Otherwise, it will be assumed to be file path and wrapped in a Device::LogFile class.

This method can take the following options:

  • :level - The logging level below which messages will be ignored.

  • :formatter - The formatter to use for outputting messages to the log.

  • :datetime_format - The format to use for log timestamps.

  • :tag_formatter - The TagFormatter to use for formatting tags.

  • :progname - The name of the program that will be recorded with each log entry.

  • :flush_seconds - The maximum number of seconds between flush calls.

  • :roll - If the log device is a file path, it will be a Device::DateRollingLogFile if this is set.

  • :max_size - If the log device is a file path, it will be a Device::SizeRollingLogFile if this is set.

All other options are passed to the device constuctor.

Parameters:

  • device (Lumberjack::Device, Object, Symbol, String) (defaults to: $stdout) —

    The device to log to.

  • options (Hash) (defaults to: {}) —

    The options for the logger.



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# File 'lib/lumberjack/logger.rb', line 69

def initialize(device = $stdout, options = {})
  options = options.dup
  self.level = options.delete(:level) || INFO
  self.progname = options.delete(:progname)
  max_flush_seconds = options.delete(:flush_seconds).to_f

  @device = open_device(device, options) if device
  self.formatter = (options[:formatter] || Formatter.new)
  @tag_formatter = (options[:tag_formatter] || TagFormatter.new)
  time_format = (options[:datetime_format] || options[:time_format])
  self.datetime_format = time_format if time_format
  @last_flushed_at = Time.now
  @silencer = true
  @tags = {}
  @closed = false

  create_flusher_thread(max_flush_seconds) if max_flush_seconds > 0
end

Instance Attribute Details

#device ⇒ Object

The device being written to



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# File 'lib/lumberjack/logger.rb', line 40

def device
  @device
end

#last_flushed_at ⇒ Object (readonly)

The time that the device was last flushed.



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# File 'lib/lumberjack/logger.rb', line 31

def last_flushed_at
  @last_flushed_at
end

#progname ⇒ String

Get the program name associated with log messages.

Returns:

  • (String) 


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# File 'lib/lumberjack/logger.rb', line 460

def progname
  thread_local_value(:lumberjack_logger_progname) || @progname
end

#silencer ⇒ Object

Set silencer to false to disable silencing the log.



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# File 'lib/lumberjack/logger.rb', line 34

def silencer
  @silencer
end

#tag_formatter ⇒ Object

The TagFormatter used for formatting tags for output



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# File 'lib/lumberjack/logger.rb', line 43

def tag_formatter
  @tag_formatter
end

Instance Method Details

#<<(msg) ⇒ void

This method returns an undefined value.

Add a message when the severity is not known.

Parameters:

  • msg (Object) —

    The message to log.



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# File 'lib/lumberjack/logger.rb', line 417

def <<(msg)
  add_entry(UNKNOWN, msg)
end

#add(severity, message = nil, progname = nil, &block) ⇒ void Also known as: log

This method returns an undefined value.

::Logger compatible method to add a log entry.

Parameters:

  • severity (Integer, Symbol, String) —

    The severity of the message.

  • message (Object) (defaults to: nil) —

    The message to log.

  • progname (String) (defaults to: nil) —

    The name of the program that is logging the message.



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# File 'lib/lumberjack/logger.rb', line 229

def add(severity, message = nil, progname = nil, &block)
  if message.nil?
    if block
      message = block
    else
      message = progname
      progname = nil
    end
  end
  add_entry(severity, message, progname)
end

#add_entry(severity, message, progname = nil, tags = nil) ⇒ void

This method returns an undefined value.

Add a message to the log with a given severity. The message can be either passed in the message argument or supplied with a block. This method is not normally called. Instead call one of the helper functions fatal, error, warn, info, or debug.

The severity can be passed in either as one of the Severity constants, or as a Severity label.

Examples:


logger.add_entry(Logger::ERROR, exception)
logger.add_entry(Logger::INFO, "Request completed")
logger.add_entry(:warn, "Request took a long time")
logger.add_entry(Logger::DEBUG){"Start processing with options #{options.inspect}"}

Parameters:

  • severity (Integer, Symbol, String) —

    The severity of the message.

  • message (Object) —

    The message to log.

  • progname (String) (defaults to: nil) —

    The name of the program that is logging the message.

  • tags (Hash) (defaults to: nil) —

    The tags to add to the log entry.



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# File 'lib/lumberjack/logger.rb', line 188

def add_entry(severity, message, progname = nil, tags = nil)
  begin
    severity = Severity.label_to_level(severity) unless severity.is_a?(Integer)
    return true unless device && severity && severity >= level

    return true if Thread.current[:lumberjack_logging]
    Thread.current[:lumberjack_logging] = true

    time = Time.now
    message = message.call if message.is_a?(Proc)
    message = formatter.format(message)
    progname ||= self.progname

    current_tags = self.tags
    tags = nil unless tags.is_a?(Hash)
    if current_tags.empty?
      tags = Tags.stringify_keys(tags) unless tags.nil?
    else
      tags = if tags.nil?
        current_tags.dup
      else
        current_tags.merge(Tags.stringify_keys(tags))
      end
    end
    tags = Tags.expand_runtime_values(tags)
    tags = tag_formatter.format(tags) if tag_formatter

    entry = LogEntry.new(time, severity, message, progname, $$, tags)
    write_to_device(entry)
  ensure
    Thread.current[:lumberjack_logging] = nil
  end
  true
end

#close ⇒ void

This method returns an undefined value.

Close the logging device.



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# File 'lib/lumberjack/logger.rb', line 255

def close
  flush
  device.close if device.respond_to?(:close)
  @closed = true
end

#closed? ⇒ Boolean

Returns true if the logging device is closed.

Returns:

  • (Boolean) —

    true if the logging device is closed.



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# File 'lib/lumberjack/logger.rb', line 264

def closed?
  @closed
end

#datetime_format ⇒ String?

Get the timestamp format on the device if it has one.

Returns:

  • (String, nil) —

    The timestamp format or nil if the device doesn’t support it.



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# File 'lib/lumberjack/logger.rb', line 91

def datetime_format
  device.datetime_format if device.respond_to?(:datetime_format)
end

#datetime_format=(format) ⇒ void

This method returns an undefined value.

Set the timestamp format on the device if it is supported.

Parameters:

  • format (String) —

    The timestamp format.



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# File 'lib/lumberjack/logger.rb', line 99

def datetime_format=(format)
  if device.respond_to?(:datetime_format=)
    device.datetime_format = format
  end
end

#debug(message_or_progname_or_tags = nil, progname_or_tags = nil, &block) ⇒ void

This method returns an undefined value.

Log a DEBUG message. The message can be passed in either the message argument or in a block.

Parameters:

  • message_or_progname_or_tags (Object) (defaults to: nil) —

    The message to log or progname if the message is passed in a block.

  • progname_or_tags (String, Hash) (defaults to: nil) —

    The name of the program that is logging the message or tags if the message is passed in a block.



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# File 'lib/lumberjack/logger.rb', line 383

def debug(message_or_progname_or_tags = nil, progname_or_tags = nil, &block)
  call_add_entry(DEBUG, message_or_progname_or_tags, progname_or_tags, &block)
end

#debug! ⇒ void

This method returns an undefined value.

Set the log level to debug.



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# File 'lib/lumberjack/logger.rb', line 397

def debug!
  self.level = DEBUG
end

#debug? ⇒ Boolean

Return true if DEBUG messages are being logged.

Returns:

  • (Boolean) 


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# File 'lib/lumberjack/logger.rb', line 390

def debug?
  level <= DEBUG
end

#error(message_or_progname_or_tags = nil, progname_or_tags = nil, &block) ⇒ void

This method returns an undefined value.

Log an ERROR message. The message can be passed in either the message argument or in a block.

Parameters:

  • message_or_progname_or_tags (Object) (defaults to: nil) —

    The message to log or progname if the message is passed in a block.

  • progname_or_tags (String, Hash) (defaults to: nil) —

    The name of the program that is logging the message or tags if the message is passed in a block.



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# File 'lib/lumberjack/logger.rb', line 308

def error(message_or_progname_or_tags = nil, progname_or_tags = nil, &block)
  call_add_entry(ERROR, message_or_progname_or_tags, progname_or_tags, &block)
end

#error! ⇒ void

This method returns an undefined value.

Set the log level to error.



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# File 'lib/lumberjack/logger.rb', line 322

def error!
  self.level = ERROR
end

#error? ⇒ Boolean

Return true if ERROR messages are being logged.

Returns:

  • (Boolean) 


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# File 'lib/lumberjack/logger.rb', line 315

def error?
  level <= ERROR
end

#fatal(message_or_progname_or_tags = nil, progname_or_tags = nil, &block) ⇒ void

This method returns an undefined value.

Log a FATAL message. The message can be passed in either the message argument or in a block.

Parameters:

  • message_or_progname_or_tags (Object) (defaults to: nil) —

    The message to log or progname if the message is passed in a block.

  • progname_or_tags (String, Hash) (defaults to: nil) —

    The name of the program that is logging the message or tags if the message is passed in a block.



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# File 'lib/lumberjack/logger.rb', line 283

def fatal(message_or_progname_or_tags = nil, progname_or_tags = nil, &block)
  call_add_entry(FATAL, message_or_progname_or_tags, progname_or_tags, &block)
end

#fatal! ⇒ void

This method returns an undefined value.

Set the log level to fatal.



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# File 'lib/lumberjack/logger.rb', line 297

def fatal!
  self.level = FATAL
end

#fatal? ⇒ Boolean

Return true if FATAL messages are being logged.

Returns:

  • (Boolean) 


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# File 'lib/lumberjack/logger.rb', line 290

def fatal?
  level <= FATAL
end

#flush ⇒ void

This method returns an undefined value.

Flush the logging device. Messages are not guaranteed to be written until this method is called.



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# File 'lib/lumberjack/logger.rb', line 246

def flush
  device.flush
  @last_flushed_at = Time.now
  nil
end

#formatter ⇒ Lumberjack::Formatter

Get the Lumberjack::Formatter used to format objects for logging as messages.

Returns:



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# File 'lib/lumberjack/logger.rb', line 145

def formatter
  if respond_to?(:tagged)
    # Wrap in an object that supports ActiveSupport::TaggedLogger API
    TaggedLoggerSupport::Formatter.new(logger: self, formatter: @_formatter)
  else
    @_formatter
  end
end

#formatter=(value) ⇒ void

This method returns an undefined value.

Set the Lumberjack::Formatter used to format objects for logging as messages.

Parameters:



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# File 'lib/lumberjack/logger.rb', line 138

def formatter=(value)
  @_formatter = (value.is_a?(TaggedLoggerSupport::Formatter) ? value.__formatter : value)
end

#info(message_or_progname_or_tags = nil, progname_or_tags = nil, &block) ⇒ void

This method returns an undefined value.

Log an INFO message. The message can be passed in either the message argument or in a block.

Parameters:

  • message_or_progname_or_tags (Object) (defaults to: nil) —

    The message to log or progname if the message is passed in a block.

  • progname_or_tags (String) (defaults to: nil) —

    The name of the program that is logging the message or tags if the message is passed in a block.



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# File 'lib/lumberjack/logger.rb', line 358

def info(message_or_progname_or_tags = nil, progname_or_tags = nil, &block)
  call_add_entry(INFO, message_or_progname_or_tags, progname_or_tags, &block)
end

#info! ⇒ void

This method returns an undefined value.

Set the log level to info.



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# File 'lib/lumberjack/logger.rb', line 372

def info!
  self.level = INFO
end

#info? ⇒ Boolean

Return true if INFO messages are being logged.

Returns:

  • (Boolean) 


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# File 'lib/lumberjack/logger.rb', line 365

def info?
  level <= INFO
end

#level ⇒ Integer Also known as: sev_threshold

Get the level of severity of entries that are logged. Entries with a lower severity level will be ignored.

Returns:

  • (Integer) —

    The severity level.



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# File 'lib/lumberjack/logger.rb', line 109

def level
  thread_local_value(:lumberjack_logger_level) || @level
end

#level=(value) ⇒ void Also known as: sev_threshold=

This method returns an undefined value.

Set the log level using either an integer level like Logger::INFO or a label like :info or “info”

Parameters:

  • value (Integer, Symbol, String) —

    The severity level.



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# File 'lib/lumberjack/logger.rb', line 120

def level=(value)
  @level = Severity.coerce(value)
end

#remove_tag(*tag_names) ⇒ void

This method returns an undefined value.

Remove a tag from the current tag context. If this is called inside a block to a call to ‘tag`, the tags will only be removed for the duration of that block. Otherwise they will be removed from the global tags.

Parameters:

  • tag_names (Array<String, Symbol>) —

    The tags to remove.



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# File 'lib/lumberjack/logger.rb', line 493

def remove_tag(*tag_names)
  thread_tags = thread_local_value(:lumberjack_logger_tags)
  if thread_tags
    tag_names.each { |name| thread_tags.delete(name.to_s) }
  else
    tag_names.each { |name| @tags.delete(name.to_s) }
  end
end

#reopen(logdev = nil) ⇒ Object

Reopen the logging device.

Parameters:

  • logdev (Object) (defaults to: nil) —

    passed through to the logging device.



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# File 'lib/lumberjack/logger.rb', line 271

def reopen(logdev = nil)
  @closed = false
  device.reopen(logdev) if device.respond_to?(:reopen)
end

#set_progname(value, &block) ⇒ void

This method returns an undefined value.

Set the program name that is associated with log messages. If a block is given, the program name will be valid only within the block.

Parameters:

  • value (String) —

    The program name to use.



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# File 'lib/lumberjack/logger.rb', line 449

def set_progname(value, &block)
  if block
    push_thread_local_value(:lumberjack_logger_progname, value, &block)
  else
    self.progname = value
  end
end

#silence(temporary_level = ERROR, &block) ⇒ Object

Silence the logger by setting a new log level inside a block. By default, only ERROR or FATAL messages will be logged.

Examples:


logger.level = Logger::INFO
logger.silence do
  do_something   # Log level inside the block is +ERROR+
end

Parameters:

  • temporary_level (Integer, String, Symbol) (defaults to: ERROR) —

    The log level to use inside the block.

Returns:

  • (Object) —

    The result of the block.



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# File 'lib/lumberjack/logger.rb', line 433

def silence(temporary_level = ERROR, &block)
  if silencer
    unless temporary_level.is_a?(Integer)
      temporary_level = Severity.label_to_level(temporary_level)
    end
    push_thread_local_value(:lumberjack_logger_level, temporary_level, &block)
  else
    yield
  end
end

#tag(tags, &block) ⇒ void

This method returns an undefined value.

Set a hash of tags on logger. If a block is given, the tags will only be set for the duration of the block. If this method is called inside such a block, the tags will only be defined on the tags in that block. When the parent block exits, all the tags will be reverted. If there is no block, then the tags will be defined as global and apply to all log statements.

Parameters:

  • tags (Hash) —

    The tags to set.



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# File 'lib/lumberjack/logger.rb', line 472

def tag(tags, &block)
  tags = Tags.stringify_keys(tags)
  thread_tags = thread_local_value(:lumberjack_logger_tags)
  if block
    merged_tags = (thread_tags ? thread_tags.merge(tags) : tags.dup)
    push_thread_local_value(:lumberjack_logger_tags, merged_tags, &block)
  elsif thread_tags
    thread_tags.merge!(tags)
    nil
  else
    @tags.merge!(tags)
    nil
  end
end

#tagged_logger! ⇒ Lumberjack::Logger

Enable this logger to function like an ActiveSupport::TaggedLogger. This will make the logger API compatible with ActiveSupport::TaggedLogger and is provided as a means of compatibility with other libraries that assume they can call the ‘tagged` method on a logger to add tags.

The tags added with this method are just strings so they are stored in the logger tags in an array under the “tagged” tag. So calling ‘logger.tagged(“foo”, “bar”)` will result in tags `=> [“foo”, “bar”]`.

Returns:



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# File 'lib/lumberjack/logger.rb', line 163

def tagged_logger!
  extend(TaggedLoggerSupport)
  self
end

#tags ⇒ Hash

Return all tags in scope on the logger including global tags set on the Lumberjack context, tags set on the logger, and tags set on the current block for the logger.

Returns:

  • (Hash) 


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# File 'lib/lumberjack/logger.rb', line 506

def tags
  tags = {}
  context_tags = Lumberjack.context_tags
  tags.merge!(context_tags) if context_tags && !context_tags.empty?
  tags.merge!(@tags) if !@tags.empty? && !thread_local_value(:lumberjack_logger_untagged)
  scope_tags = thread_local_value(:lumberjack_logger_tags)
  tags.merge!(scope_tags) if scope_tags && !scope_tags.empty?
  tags
end

#unknown(message_or_progname_or_tags = nil, progname_or_tags = nil, &block) ⇒ void

This method returns an undefined value.

Log a message when the severity is not known. Unknown messages will always appear in the log. The message can be passed in either the message argument or in a block.

Parameters:

  • message_or_progname_or_tags (Object) (defaults to: nil) —

    The message to log or progname if the message is passed in a block.

  • progname_or_tags (String, Hash) (defaults to: nil) —

    The name of the program that is logging the message or tags if the message is passed in a block.



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# File 'lib/lumberjack/logger.rb', line 409

def unknown(message_or_progname_or_tags = nil, progname_or_tags = nil, &block)
  call_add_entry(UNKNOWN, message_or_progname_or_tags, progname_or_tags, &block)
end

#untagged(&block) ⇒ void

This method returns an undefined value.

Remove all tags on the current logger and logging context within a block. You can still set new block scoped tags within theuntagged block and provide tags on individual log methods.



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# File 'lib/lumberjack/logger.rb', line 521

def untagged(&block)
  Lumberjack.use_context(nil) do
    scope_tags = thread_local_value(:lumberjack_logger_tags)
    untagged = thread_local_value(:lumberjack_logger_untagged)
    begin
      set_thread_local_value(:lumberjack_logger_untagged, true)
      set_thread_local_value(:lumberjack_logger_tags, nil)
      tag({}, &block)
    ensure
      set_thread_local_value(:lumberjack_logger_untagged, untagged)
      set_thread_local_value(:lumberjack_logger_tags, scope_tags)
    end
  end
end

#warn(message_or_progname_or_tags = nil, progname_or_tags = nil, &block) ⇒ void

This method returns an undefined value.

Log a WARN message. The message can be passed in either the message argument or in a block.

Parameters:

  • message_or_progname_or_tags (Object) (defaults to: nil) —

    The message to log or progname if the message is passed in a block.

  • progname_or_tags (String, Hash) (defaults to: nil) —

    The name of the program that is logging the message or tags if the message is passed in a block.



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# File 'lib/lumberjack/logger.rb', line 333

def warn(message_or_progname_or_tags = nil, progname_or_tags = nil, &block)
  call_add_entry(WARN, message_or_progname_or_tags, progname_or_tags, &block)
end

#warn! ⇒ void

This method returns an undefined value.

Set the log level to warn.



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# File 'lib/lumberjack/logger.rb', line 347

def warn!
  self.level = WARN
end

#warn? ⇒ Boolean

Return true if WARN messages are being logged.

Returns:

  • (Boolean) 


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# File 'lib/lumberjack/logger.rb', line 340

def warn?
  level <= WARN
end

#with_level(severity, &block) ⇒ Object

Adjust the log level during the block execution for the current Fiber only.

Parameters:

  • severity (Integer, Symbol, String) —

    The severity level.

Returns:

  • (Object) —

    The result of the block.



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# File 'lib/lumberjack/logger.rb', line 130

def with_level(severity, &block)
  push_thread_local_value(:lumberjack_logger_level, Severity.coerce(severity), &block)
end