JezK
Edit File: incident_logger.rb
require 'logger' module Celluloid # A logger that holds all messages in circular buffers, then flushes the buffers # when an event occurs at a configurable severity threshold. # # Unlike ruby's Logger, this class only supports a single progname. class IncidentLogger module Severity include ::Logger::Severity TRACE = -1 def severity_to_string(severity) case severity when TRACE then 'TRACE' when DEBUG then 'DEBUG' when INFO then 'INFO' when WARN then 'WARN' when ERROR then 'ERROR' when FATAL then 'FATAL' when UNKNOWN then 'UNKNOWN' end end end include Severity # The progname (facility) for this instance. attr_accessor :progname # The logging level. Messages below this severity will not be logged at all. attr_accessor :level # The incident threshold. Messages at or above this severity will generate an # incident and be published to incident reporters. attr_accessor :threshold # The buffer size limit. Each log level will retain this number of messages # at maximum. attr_accessor :sizelimit attr_accessor :buffers # Create a new IncidentLogger. def initialize(progname=nil, options={}) @progname = progname || "default" @level = options[:level] || DEBUG @threshold = options[:threshold] || ERROR @sizelimit = options[:sizelimit] || 100 @buffer_mutex = Mutex.new @buffers = Hash.new do |progname_hash, _progname| @buffer_mutex.synchronize do progname_hash[_progname] = Hash.new do |severity_hash, severity| severity_hash[severity] = RingBuffer.new(@sizelimit) end end end # When the IncidentLogger itself encounters an error, it falls back to logging to stderr @fallback_logger = ::Logger.new(STDERR) @fallback_logger.progname = "FALLBACK" end # add an event. def add(severity, message=nil, progname=nil, &block) progname ||= @progname severity ||= UNKNOWN if severity < @level return event.id end if message.nil? && !block_given? message = progname progname = @progname end event = LogEvent.new(severity, message, progname, &block) @buffers[progname][severity] << event if severity >= @threshold begin Celluloid::Notifications.notifier.async.publish(incident_topic, create_incident(event)) rescue => ex @fallback_logger.error(ex) end end event.id end alias :log :add # See docs for Logger#info def trace (progname=nil, &block); add(TRACE, nil, progname, &block); end def debug (progname=nil, &block); add(DEBUG, nil, progname, &block); end def info (progname=nil, &block); add(INFO, nil, progname, &block); end def warn (progname=nil, &block); add(WARN, nil, progname, &block); end def error (progname=nil, &block); add(ERROR, nil, progname, &block); end def fatal (progname=nil, &block); add(FATAL, nil, progname, &block); end def unknown (progname=nil, &block); add(UNKNOWN, nil, progname, &block); end def flush messages = [] @buffer_mutex.synchronize do @buffers.each do |progname, severities| severities.each do |severity, buffer| messages += buffer.flush end end end messages.sort end def clear @buffer_mutex.synchronize do @buffers.each { |buffer| buffer.clear } end end def create_incident(event=nil) Incident.new(flush, event) end def incident_topic "log.incident.#{@progname}" end end end