Support environment variable for sample rate

Author: majorgreys

ddtrace/settings/integration.py

@@ -44,6 +44,7 @@ def __init__(self, global_config, name, *args, **kwargs):
         if analytics_enabled_env is not None:
             analytics_enabled_env = asbool(analytics_enabled_env)
         self.setdefault('analytics_enabled', analytics_enabled_env)
+        self.setdefault('analytics_sample_rate', float(get_env(name, 'analytics_sample_rate', 1.0)))
 
     def __deepcopy__(self, memodict=None):
         new = IntegrationConfig(self.global_config, deepcopy(dict(self)))

tests/unit/test_settings.py

@@ -127,11 +127,17 @@ def test_environment_analytics_enabled(self):
         with self.override_env(dict(DD_FOO_ANALYTICS_ENABLED='True')):
             config = Config()
             self.assertTrue(config.foo.analytics_enabled)
+            self.assertEqual(config.foo.analytics_sample_rate, 1.0)
 
         with self.override_env(dict(DD_FOO_ANALYTICS_ENABLED='False')):
             config = Config()
             self.assertFalse(config.foo.analytics_enabled)
 
+        with self.override_env(dict(DD_FOO_ANALYTICS_ENABLED='True', DD_FOO_ANALYTICS_SAMPLE_RATE='0.5')):
+            config = Config()
+            self.assertTrue(config.foo.analytics_enabled)
+            self.assertEqual(config.foo.analytics_sample_rate, 0.5)
+
     def test_analytics_enabled_attribute(self):
         """" Confirm environment variable and kwargs are handled properly """
         ic = IntegrationConfig(self.config, 'foo', analytics_enabled=True)