class Hitimes::Metric
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.
Attributes
An additional hash of data to associate with the metric
The ‘name’ to associate with the metric
the number of seconds as a float since the sampling_start_time
Public Class Methods
Source
# File lib/hitimes/metric.rb, line 44 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
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.
Public Instance Methods
Source
# File lib/hitimes/metric.rb, line 62 def sampling_start_time return unless @sampling_start_interval @sampling_start_time ||= utc_microseconds end
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.
Source
# File lib/hitimes/metric.rb, line 84 def sampling_stop_time return unless @sampling_delta.positive? (sampling_start_time + (@sampling_delta * 1_000_000)) end
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.
Source
# File lib/hitimes/metric.rb, line 97 def to_hash { "sampling_start_time" => sampling_start_time, "sampling_stop_time" => sampling_stop_time, "additional_data" => additional_data, "name" => name, } end
Convert the metric to a Hash.
Source
# File lib/hitimes/metric.rb, line 110 def utc_microseconds Time.now.gmtime.to_f * 1_000_000 end
The current time in microseconds from the UNIX Epoch in the UTC