def test_compound_metrics():
metrics1 = Metrics()
metrics2 = Metrics()
metrics1.register(Label('value', 'first'))
metrics2.register(Label('value', 'second'))
assert CompoundMetrics(metrics1, metrics2).sample() == {'value': 'second'}
metrics1.register(Label('other', 'third'))
assert CompoundMetrics(metrics1, metrics2).sample() == {
'value': 'second',
'other': 'third'
}
def test_observable():
class Derp(Observable):
def __init__(self):
self.metrics.register(Label('value', 'derp value'))
metrics = Metrics()
metrics.register_observable('derpspace', Derp())
assert metrics.sample() == {'derpspace.value': 'derp value'}
def test_metric_sample():
metrics = Metrics()
sampler = MetricSampler(metrics)
assert sampler.sample() == {}
sampler.iterate()
assert sampler.sample() == {}
metrics.register(Label('herp', 'derp'))
assert sampler.sample() == {}
sampler.iterate()
assert sampler.sample() == {'herp': 'derp'}
def test_metric_read_write():
metrics = Metrics()
with temporary_file() as fp:
os.unlink(fp.name)
writer = DiskMetricWriter(metrics, fp.name)
reader = DiskMetricReader(fp.name)
assert reader.sample() == {}
reader.iterate()
assert reader.sample() == {}
writer.iterate()
assert reader.sample() == {}
reader.iterate()
assert reader.sample() == {}
metrics.register(Label('herp', 'derp'))
writer.iterate()
assert reader.sample() == {}
reader.iterate()
assert reader.sample() == {'herp': 'derp'}
