statsd-instrument

# You can pass a key and a ms value
StatsD.measure('GoogleBase.insert', 2.55)

# or more commonly pass a block that calls your code
StatsD.measure('GoogleBase.insert') do
  GoogleBase.insert(product)
end

# increments default to +1
StatsD.increment('GoogleBase.insert')
# you can also specify how much to increment the key by
StatsD.increment('GoogleBase.insert', 10)
# you can also specify a sample rate, so only 1/10 of events
# actually get to statsd. Useful for very high volume data
StatsD.increment('GoogleBase.insert', sample_rate: 0.1)

StatsD.gauge('GoogleBase.queued', 12, sample_rate: 1.0)

# Submit the customer ID to the set. It will only be counted if it hasn't been seen before.
StatsD.set('GoogleBase.customers', "12345", sample_rate: 1.0)

StatsD.histogram('Order.value', order.value_in_usd.to_f, tags: { source: 'POS' })

StatsD.distribution('shipit.redis_connection', 3)

StatsD.event('shipit.deploy', 'started')

StatsD.service_check('shipit.redis_connection', 'ok')

GoogleBase.extend StatsD::Instrument

GoogleBase.statsd_measure :insert, 'GoogleBase.insert'

GoogleBase.statsd_count :insert, 'GoogleBase.insert'

GoogleBase.statsd_count_if :insert, 'GoogleBase.insert'

GoogleBase.statsd_count_if :insert, 'GoogleBase.insert' do |response|
  response.code == 200
end

GoogleBase.statsd_count_success :insert, 'GoogleBase.insert'

GoogleBase.statsd_count_success :insert, 'GoogleBase.insert' do |response|
  response.code == 200
end

AWS::S3::Base.singleton_class.statsd_measure :request, 'S3.request'

GoogleBase.statsd_count :insert, lambda{|object, args| object.class.to_s.downcase + "." + args.first.to_s + ".insert" }

StatsD.increment('my.counter', tags: ['env:production', 'unicorn'])
GoogleBase.statsd_count :insert, 'GoogleBase.insert', tags: ['env:production']

metric_tagger = lambda { |object, args| { "key": args.first } }
GoogleBase.statsd_count(:insert, 'GoogleBase.insert', tags: metric_tagger)

class MyTestcase < Minitest::Test
  include StatsD::Instrument::Assertions

  def test_some_metrics
    # This will pass if there is exactly one matching StatsD call
    # it will ignore any other, non matching calls.
    assert_statsd_increment('counter.name', sample_rate: 1.0) do
      StatsD.increment('unrelated') # doesn't match
      StatsD.increment('counter.name', sample_rate: 1.0) # matches
      StatsD.increment('counter.name', sample_rate: 0.1) # doesn't match
    end

    # Set `times` if there will be multiple matches:
    assert_statsd_increment('counter.name', times: 2) do
      StatsD.increment('unrelated') # doesn't match
      StatsD.increment('counter.name', sample_rate: 1.0) # matches
      StatsD.increment('counter.name', sample_rate: 0.1) # matches too
    end
  end

  def test_no_udp_traffic
    # Verifies no StatsD calls occurred at all.
    assert_no_statsd_calls do
      do_some_work
    end

    # Verifies no StatsD calls occurred for the given metric.
    assert_no_statsd_calls('metric_name') do
      do_some_work
    end
  end

  def test_more_complicated_stuff
    # capture_statsd_calls will capture all the StatsD calls in the
    # given block, and returns them as an array. You can then run your
    # own assertions on it.
    metrics = capture_statsd_calls do
      StatsD.increment('mycounter', sample_rate: 0.01)
    end

    assert_equal 1, metrics.length
    assert_equal 'mycounter', metrics[0].name
    assert_equal :c, metrics[0].type
    assert_equal 1, metrics[0].value
    assert_equal 0.01, metrics[0].sample_rate
  end
end

RSpec.configure do |config|
  config.include StatsD::Instrument::Matchers
end

RSpec.describe 'Matchers' do
  context 'trigger_statsd_increment' do
    it 'will pass if there is exactly one matching StatsD call' do
      expect { StatsD.increment('counter') }.to trigger_statsd_increment('counter')
    end

    it 'will pass if it matches the correct number of times' do
      expect {
        2.times do
          StatsD.increment('counter')
        end
      }.to trigger_statsd_increment('counter', times: 2)
    end

    it 'will pass if it matches argument' do
      expect {
        StatsD.measure('counter', 0.3001)
      }.to trigger_statsd_measure('counter', value: be_between(0.29, 0.31))
    end

    it 'will pass if there is no matching StatsD call on negative expectation' do
      expect { StatsD.increment('other_counter') }.not_to trigger_statsd_increment('counter')
    end
  end
end