Class: Librato::Metrics::Aggregator

Inherits:
Object
  • Object
show all
Includes:
Processor
Defined in:
lib/librato/metrics/aggregator.rb

Overview

If you are measuring something very frequently you can sample into an aggregator and it will track and submit a single aggregate measurement

Examples:

aggregator = Libato::Metrics::Aggregator.new

40.times do
  # do work...
  aggregator.add 'work.time' => work_time
end

# send directly
aggregator.submit

# or merge into a queue for submission
queue.merge!(aggregator)

Constant Summary collapse

SEPARATOR =

must not be in valid tags and/or source criteria

'%%'

Constants included from Processor

Processor::MEASUREMENTS_PER_REQUEST

Instance Attribute Summary collapse

Attributes included from Processor

#last_submit_time, #per_request, #prefix, #tags

Instance Method Summary collapse

Methods included from Processor

#client, #has_tags?, #persister, #submit, #time

Constructor Details

#initialize(opts = {}) ⇒ Aggregator

Returns a new instance of Aggregator.

Parameters:

  • opts (Hash) (defaults to: {}) —

    a customizable set of options

Options Hash (opts):

  • :autosubmit_interval (Integer) —

    If set the aggregator will auto-submit if the given number of seconds has passed when a new metric is added.

  • :clear_failures (Boolean) —

    Should the aggregator remove all stored data if it runs into problems with a request? (default: false)

  • :client (Client) —

    The client object to use to connect to Metrics. (default: Librato::Metrics.client)

  • :measure_time (Time|Integer) —

    A default measure_time to use for measurements added.

  • :prefix (String) —

    If set will apply the given prefix to all metric names of measurements added.

  • :source (String) —

    The default source to use for measurements added.



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# File 'lib/librato/metrics/aggregator.rb', line 38

def initialize(opts={})
  @aggregated = {}
  setup_common_options(opts)
end

Instance Attribute Details

#source ⇒ Object (readonly)

Returns the value of attribute source.



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# File 'lib/librato/metrics/aggregator.rb', line 30

def source
  @source
end

Instance Method Details

#add(measurements) ⇒ Aggregator

Add a metric entry to the metric set:

Examples:

Basic use

aggregator.add 'request.time' => 30.24

With a custom source

aggregator.add 'request.time' => {value: 20.52, source: 'staging'}

Parameters:

  • measurements (Hash) —

    measurements to add

Returns:



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# File 'lib/librato/metrics/aggregator.rb', line 53

def add(measurements)
  measurements.each do |metric, data|
    entry = {}
    if @prefix
      metric = "#{@prefix}.#{metric}"
    end
    entry[:name] = metric.to_s
    if data.respond_to?(:each) # hash form
      validate_parameters(data)
      value = data[:value]
      if data[:source]
        metric = "#{metric}#{SEPARATOR}#{data[:source]}"
        entry[:source] = data[:source].to_s
      elsif data[:tags] && data[:tags].respond_to?(:each)
        metric = Librato::Metrics::Util.build_key_for(metric.to_s, data[:tags])
        entry[:tags] = data[:tags]
      end
    else
      value = data
    end

    @aggregated[metric] = {} unless @aggregated[metric]
    @aggregated[metric][:aggregate] ||= Aggregate.new
    @aggregated[metric][:aggregate] << value
    @aggregated[metric].merge!(entry)
  end
  autosubmit_check
  self
end

#clear ⇒ Object Also known as: flush

Remove all queued metrics



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# File 'lib/librato/metrics/aggregator.rb', line 92

def clear
  @aggregated = {}
end

#empty? ⇒ Boolean

Returns true if aggregate contains no measurements

Returns:

  • (Boolean) 


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# File 'lib/librato/metrics/aggregator.rb', line 86

def empty?
  @aggregated.empty?
end

#queued ⇒ Object

Returns currently queued data



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# File 'lib/librato/metrics/aggregator.rb', line 99

def queued
  entries = []
  multidimensional = has_tags?

  @aggregated.each_value do |data|
    entry = {
      name: data[:name],
      count: data[:aggregate].count,
      sum: data[:aggregate].sum,
      # TODO: make float/non-float consistent in the gem
      min: data[:aggregate].min.to_f,
      max: data[:aggregate].max.to_f
      # TODO: expose v.sum2 and include
    }
    if data[:source]
      entry[:source] = data[:source]
    elsif data[:tags]
      multidimensional = true
      entry[:tags] = data[:tags]
    end
    multidimensional = true if data[:time]
    entries << entry
  end
  time = multidimensional ? :time : :measure_time
  req =
    if multidimensional
      { measurements: entries }
    else
      { gauges: entries }
    end
  req[:source] = @source if @source
  req[:tags] = @tags if has_tags?
  req[time] = @time if @time

  req
end