statsd_subscriber_spec.rb

require 'helper'
require 'flipper/adapters/memory'
require 'flipper/instrumentation/statsd'

describe Flipper::Instrumentation::StatsdSubscriber do
  let(:statsd_client) { Statsd.new }
  let(:socket) { FakeUDPSocket.new }
  let(:adapter) { Flipper::Adapters::Memory.new }
  let(:flipper) {
    Flipper.new(adapter, :instrumenter => ActiveSupport::Notifications)
  }

  let(:user) { user = Struct.new(:flipper_id).new('1') }

  before do
    described_class.client = statsd_client
    Thread.current[:statsd_socket] = socket
  end

  after do
    described_class.client = nil
    Thread.current[:statsd_socket] = nil
  end

  def assert_timer(metric)
    regex = /#{Regexp.escape metric}\:\d+\|ms/
    socket.buffer.detect { |op| op.first =~ regex }.should_not be_nil
  end

  def assert_counter(metric)
    socket.buffer.detect { |op| op.first == "#{metric}:1|c" }.should_not be_nil
  end

  context "for enabled feature" do
    it "updates feature metrics when calls happen" do
      flipper[:stats].enable(user)
      assert_timer 'flipper.feature_operation.enable'

      flipper[:stats].enabled?(user)
      assert_timer 'flipper.feature_operation.enabled'
      assert_counter 'flipper.feature.stats.enabled'
    end
  end

  context "for disabled feature" do
    it "updates feature metrics when calls happen" do
      flipper[:stats].disable(user)
      assert_timer 'flipper.feature_operation.disable'

      flipper[:stats].enabled?(user)
      assert_timer 'flipper.feature_operation.enabled'
      assert_counter 'flipper.feature.stats.disabled'
    end
  end

  it "updates adapter metrics when calls happen" do
    flipper[:stats].enable(user)
    assert_timer 'flipper.adapter.memory.enable'

    flipper[:stats].enabled?(user)
    assert_timer 'flipper.adapter.memory.get'

    flipper[:stats].disable(user)
    assert_timer 'flipper.adapter.memory.disable'
  end

  it "updates gate metrics when calls happen" do
    flipper[:stats].enable(user)
    flipper[:stats].enabled?(user)

    assert_timer 'flipper.gate_operation.boolean.open'
    assert_timer 'flipper.feature.stats.gate_operation.boolean.open'
    assert_counter 'flipper.feature.stats.gate.actor.open'
    assert_counter 'flipper.feature.stats.gate.boolean.closed'
  end
end