Rename FixedRateSampler to ProbabilitySampler (#61)

Author: liyanhui1228

README.rst

@@ -80,15 +80,15 @@ Samplers
 
 You can specify different samplers when initializing a tracer, default
 is using ``AlwaysOnSampler``, the other options are ``AlwaysOffSampler``
-and ``FixedRateSampler``
+and ``ProbabilitySampler``
 
 .. code:: python
 
-    from opencensus.trace.samplers import fixed_rate
+    from opencensus.trace.samplers import probability
     from opencensus.trace import request_tracer
 
     # Sampling the requests at the rate equals 0.5
-    sampler = fixed_rate.FixedRateSampler(rate=0.5)
+    sampler = probability.ProbabilitySampler(rate=0.5)
     tracer = request_tracer.RequestTracer(sampler=sampler)
 
 Exporters
@@ -185,7 +185,7 @@ Customize the sampler, reporter, propagator in the ``settings.py`` file:
 ::
 
     OPENCENSUS_TRACE = {
-        'SAMPLER': 'opencensus.trace.samplers.fixed_rate.FixedRateSampler',
+        'SAMPLER': 'opencensus.trace.samplers.probability.ProbabilitySampler',
         'REPORTER': 'opencensus.trace.reporters.print_reporter.PrintReporter',
         'PROPAGATOR': 'opencensus.trace.propagation.google_cloud_format.'
                       'GoogleCloudFormatPropagator',

trace/opencensus/trace/ext/django/middleware.py

@@ -20,7 +20,7 @@
 from opencensus.trace import labels_helper
 from opencensus.trace import request_tracer
 from opencensus.trace import execution_context
-from opencensus.trace.samplers import fixed_rate
+from opencensus.trace.samplers import probability
 
 HTTP_METHOD = labels_helper.STACKDRIVER_LABELS['HTTP_METHOD']
 HTTP_URL = labels_helper.STACKDRIVER_LABELS['HTTP_URL']
@@ -95,9 +95,9 @@ def __init__(self, get_response=None):
         self._propagator = settings.PROPAGATOR
 
         # Initialize the sampler
-        if self._sampler.__name__ == 'FixedRateSampler':
+        if self._sampler.__name__ == 'ProbabilitySampler':
             _rate = settings.params.get(
-                SAMPLING_RATE, fixed_rate.DEFAULT_SAMPLING_RATE)
+                SAMPLING_RATE, probability.DEFAULT_SAMPLING_RATE)
             self.sampler = self._sampler(_rate)
         else:
             self.sampler = self._sampler()

trace/opencensus/trace/samplers/__init__.py

@@ -15,8 +15,8 @@
 from opencensus.trace.samplers.always_off import AlwaysOffSampler
 from opencensus.trace.samplers.always_on import AlwaysOnSampler
 from opencensus.trace.samplers.base import Sampler
-from opencensus.trace.samplers.fixed_rate import FixedRateSampler
+from opencensus.trace.samplers.probability import ProbabilitySampler
 
 
 __all__ = ['Sampler', 'AlwaysOnSampler', 'AlwaysOffSampler',
-           'FixedRateSampler']
+           'ProbabilitySampler']

…/opencensus/trace/samplers/fixed_rate.py …opencensus/trace/samplers/probability.pytrace/opencensus/trace/samplers/fixed_rate.py renamed to trace/opencensus/trace/samplers/probability.py trace/opencensus/trace/samplers/fixed_rate.py renamed to trace/opencensus/trace/samplers/probability.py

@@ -19,7 +19,7 @@
 MAX_VALUE = 0xffffffffffffffff
 
 
-class FixedRateSampler(Sampler):
+class ProbabilitySampler(Sampler):
     """Sample a request at a fixed rate.
 
     :type rate: float

trace/tests/unit/ext/django/test_middleware.py

@@ -120,9 +120,9 @@ def test_constructor_zipkin(self):
         self.assertEqual(middleware.exporter.host_name, host_name)
         self.assertEqual(middleware.exporter.port, port)
 
-    def test_constructor_fixed_rate_sampler(self):
+    def test_constructor_probability_sampler(self):
         from opencensus.trace.ext.django import middleware
-        from opencensus.trace.samplers import fixed_rate
+        from opencensus.trace.samplers import probability
         from opencensus.trace.exporters import print_exporter
         from opencensus.trace.propagation import google_cloud_format
 
@@ -133,7 +133,7 @@ def test_constructor_fixed_rate_sampler(self):
 
         patch_sampler = mock.patch(
             'opencensus.trace.ext.django.config.settings.SAMPLER',
-            fixed_rate.FixedRateSampler)
+            probability.ProbabilitySampler)
         patch_exporter = mock.patch(
             'opencensus.trace.ext.django.config.settings.EXPORTER',
             print_exporter.PrintExporter)
@@ -145,14 +145,14 @@ def test_constructor_fixed_rate_sampler(self):
         with patch_sampler, patch_exporter, patch_params:
             middleware = middleware.OpencensusMiddleware()
 
-        self.assertIs(middleware._sampler, fixed_rate.FixedRateSampler)
+        self.assertIs(middleware._sampler, probability.ProbabilitySampler)
         self.assertIs(
             middleware._exporter, print_exporter.PrintExporter)
         self.assertIs(
             middleware._propagator,
             google_cloud_format.GoogleCloudFormatPropagator)
 
-        assert isinstance(middleware.sampler, fixed_rate.FixedRateSampler)
+        assert isinstance(middleware.sampler, probability.ProbabilitySampler)
         assert isinstance(
             middleware.exporter, print_exporter.PrintExporter)
         assert isinstance(

…e/tests/unit/samplers/test_fixed_rate.py …/tests/unit/samplers/test_probability.pytrace/tests/unit/samplers/test_fixed_rate.py renamed to trace/tests/unit/samplers/test_probability.py trace/tests/unit/samplers/test_fixed_rate.py renamed to trace/tests/unit/samplers/test_probability.py

@@ -14,53 +14,53 @@
 
 import unittest
 
-from opencensus.trace.samplers import fixed_rate
+from opencensus.trace.samplers import probability
 
 
-class TestFixedRateSampler(unittest.TestCase):
+class TestProbabilitySampler(unittest.TestCase):
 
     def test_constructor_invalid(self):
         with self.assertRaises(ValueError):
-            fixed_rate.FixedRateSampler(rate=2)
+            probability.ProbabilitySampler(rate=2)
 
     def test_constructor_valid(self):
         rate = 0.8
         trace_id = 'f8739df974a4481f98748cd92b27177d'
-        sampler = fixed_rate.FixedRateSampler(rate=rate)
+        sampler = probability.ProbabilitySampler(rate=rate)
 
         self.assertEqual(sampler.rate, rate)
 
     def test_constructor_default(self):
         rate = 0.5
         trace_id = 'f8739df974a4481f98748cd92b27177d'
-        sampler = fixed_rate.FixedRateSampler()
+        sampler = probability.ProbabilitySampler()
 
         self.assertEqual(sampler.rate, rate)
 
     def test_should_sample_smaller(self):
         trace_id = 'f8739df974a4481f98748cd92b27177d'
-        sampler = fixed_rate.FixedRateSampler(rate=1)
+        sampler = probability.ProbabilitySampler(rate=1)
         should_sample = sampler.should_sample(trace_id=trace_id)
 
         self.assertTrue(should_sample)
 
     def test_should_sample_greater(self):
         trace_id = 'f8739df974a4481f98748cd92b27177d'
-        sampler = fixed_rate.FixedRateSampler(rate=0)
+        sampler = probability.ProbabilitySampler(rate=0)
         should_sample = sampler.should_sample(trace_id=trace_id)
 
         self.assertFalse(should_sample)
 
     def test_should_sample_trace_id_sampled(self):
         trace_id = '00000000000000000000000000000000'
-        sampler = fixed_rate.FixedRateSampler(rate=0.5)
+        sampler = probability.ProbabilitySampler(rate=0.5)
         should_sample = sampler.should_sample(trace_id=trace_id)
 
         self.assertTrue(should_sample)
 
     def test_should_sample_trace_id_not_sampled(self):
         trace_id = 'ffffffffffffffffffffffffffffffff'
-        sampler = fixed_rate.FixedRateSampler(rate=0.5)
+        sampler = probability.ProbabilitySampler(rate=0.5)
         should_sample = sampler.should_sample(trace_id=trace_id)
 
         self.assertFalse(should_sample)