def test_read_returns_a_timestamp_and_an_estimation_of_the_number_of_samples_taken(self):
mock_time = MockTime()
guesstimator = Guesstimator(redis_host='localhost', random=MockRandom(), time=mock_time, environment='test')
guesstimator.create_sample_set(
name='50-percent-sample',
recording_frequency=0.5
)
guesstimator.record('50-percent-sample')
guesstimator.record('50-percent-sample')
guesstimator.record('50-percent-sample')
guesstimator.record('50-percent-sample')
timestamp, samples_taken = guesstimator.read('50-percent-sample')
self.assertEqual(4, samples_taken)
self.assertEqual(mock_time.time, timestamp)
guesstimator.create_sample_set(
name='25-percent-sample',
recording_frequency=0.25
)
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
timestamp, samples_taken = guesstimator.read('25-percent-sample')
self.assertEqual(8, samples_taken)
def test_create_sample_set_populates_hash_with_parameters_provided(self):
mock_time = MockTime()
guesstimator = Guesstimator(redis_host='localhost', time=mock_time, environment='test')
guesstimator.create_sample_set(
name='foobar-sample',
recording_frequency=0.05
)
self.assertEqual( '0.05', self.redis.hget( guesstimator._get_hash_key('foobar-sample'), 'recording_frequency' ) )
self.assertEqual( '0', self.redis.hget( guesstimator._get_hash_key('foobar-sample'), 'samples_taken' ) )
self.assertEqual( '%s' % mock_time.time, self.redis.hget( guesstimator._get_hash_key('foobar-sample'), 'sample_start_time' ) )
def test_record_increments_the_number_of_samples_taken_with_the_appropriate_frequency(self):
guesstimator = Guesstimator(redis_host='localhost', random=MockRandom(), environment='test')
guesstimator.create_sample_set(
name='100-percent-sample',
recording_frequency=1.0
)
guesstimator.record('100-percent-sample')
guesstimator.record('100-percent-sample')
self.assertEqual( '2', self.redis.hget( guesstimator._get_hash_key('100-percent-sample'), 'samples_taken' ) )
guesstimator.create_sample_set(
name='50-percent-sample',
recording_frequency=0.5
)
guesstimator.record('50-percent-sample')
guesstimator.record('50-percent-sample')
guesstimator.record('50-percent-sample')
guesstimator.record('50-percent-sample')
self.assertEqual( '3', self.redis.hget( guesstimator._get_hash_key('50-percent-sample'), 'samples_taken' ) )
guesstimator.create_sample_set(
name='25-percent-sample',
recording_frequency=0.25
)
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
guesstimator.record('25-percent-sample')
self.assertEqual( '2', self.redis.hget( guesstimator._get_hash_key('25-percent-sample'), 'samples_taken' ) )
def test_reset_resets_timestamp_and_samples_taken(self):
mock_time = MockTime()
new_time = 1345576088.71
guesstimator = Guesstimator(redis_host='localhost', random=MockRandom(), time=mock_time, environment='test')
guesstimator.create_sample_set(
name='100-percent-sample',
recording_frequency=1.0
)
guesstimator.record('100-percent-sample')
guesstimator.record('100-percent-sample')
timestamp, samples_taken = guesstimator.read('100-percent-sample')
self.assertEqual( '2', self.redis.hget( guesstimator._get_hash_key('100-percent-sample'), 'samples_taken' ) )
self.assertFalse( timestamp == new_time )
mock_time.time = new_time
guesstimator.reset('100-percent-sample')
timestamp, samples_taken = guesstimator.read('100-percent-sample')
self.assertEqual( '0', self.redis.hget( guesstimator._get_hash_key('100-percent-sample'), 'samples_taken' ) )
self.assertEqual( new_time, timestamp )
This example demonstrates what a reader that consumes guesstimator's data might look like.
in the wild this might be a Ganglia or Munin plugin.
"""
import time
from guesstimator import Guesstimator
from redis import Redis
guesstimator = Guesstimator(environment='example')
sample_set_name = 'count-operations'
redis = Redis('localhost')
# Initialize a sample set, this should only be done once.
if not sample_set_name in guesstimator.list_sample_sets():
guesstimator.create_sample_set(
name=sample_set_name
)
while True:
time.sleep(10)
operations = float( redis.get('guesstimator_example_actual_operation_count') )
timestamp, estimated_operations = guesstimator.read(sample_set_name)
print "Metrics:\n\toperation count: \t\033[32m%s\033[m\n\testimated count:\t\033[31m%s\033[m\n\n\tOperations per-second:\t%s\n---------" % (
operations,
estimated_operations,
( operations / (time.time() - timestamp) )
)
guesstimator.reset(sample_set_name)
redis.set('guesstimator_example_actual_operation_count', 0)
def test_create_sample_set_creates_populates_sample_set_list(self):
guesstimator = Guesstimator(redis_host='localhost', environment='test')
self.assertEqual( self.redis.type( guesstimator._sample_set_list_key ), 'none')
guesstimator.create_sample_set('foobar-sample')
self.assertTrue( 'foobar-sample' in guesstimator.list_sample_sets() )
