JezK
Edit File: metric.rb
#-- # Copyright (c) 2008, 2009 Jeremy Hinegardner # All rights reserved. See LICENSE and/or COPYING for details. #++ module Hitimes # # Metric hold the common meta information for all derived metric classes # # All metrics hold the meta information of: # # * The name of the metric # * The time of day the first measurement is taken # * The time of day the last measurement is taken # * additional data # # Each derived class is assumed to set the sampling_start_time and # sampling_stop_time appropriately. # # Metric itself should generally not be used. Only use the derived classes. # class Metric # the number of seconds as a float since the sampling_start_time attr_reader :sampling_delta # An additional hash of data to associate with the metric attr_reader :additional_data # The 'name' to associate with the metric attr_reader :name # # :call-seq: # Metric.new( 'my_metric' ) -> Metric # Metric.new( 'my_metric', 'foo' => 'bar', 'this' => 42 ) -> Metric # # Create a new ValueMetric giving it a name and additional data. # # +additional_data+ may be anything that follows the +to_hash+ protocol. # +name+ may be anything that follows the +to_s+ protocol. # def initialize( name, additional_data = {} ) @sampling_start_time = nil @sampling_start_interval = nil @sampling_delta = 0 @name = name.to_s @additional_data = additional_data.to_hash end # # :call-seq: # metric.sampling_start_time -> Float or nil # # The time at which the first sample was taken. # This is the number of microseconds since UNIX epoch UTC as a Float # # If the metric has not started measuring then the start time is nil. # def sampling_start_time if @sampling_start_interval then @sampling_start_time ||= self.utc_microseconds() else nil end end # # :call-seq: # metric.sampling_stop_time -> Float or nil # # The time at which the last sample was taken # This is the number of microseconds since UNIX epoch UTC as a Float # # If the metric has not completely measured at least one thing then # stop time is nil. # # Because accessing the actual 'time of day' is an expesive operation, we # only get the time of day at the beginning of the first measurement and we # keep track of the offset from that point in @sampling_delta. # # When sampling_stop_time is called, the actual time of day is caculated. # def sampling_stop_time if @sampling_delta > 0 then (self.sampling_start_time + (@sampling_delta * 1_000_000)) else nil end end # # :call-seq: # metric.to_hash -> Hash # metric.to_hash # # Convert the metric to a Hash. # def to_hash { 'sampling_start_time' => self.sampling_start_time, 'sampling_stop_time' => self.sampling_stop_time, 'additional_data' => self.additional_data, 'name' => self.name } end # # :call-seq: # metric.utc_microseconds -> Float # # The current time in microseconds from the UNIX Epoch in the UTC # def utc_microseconds Time.now.gmtime.to_f * 1_000_000 end end end