[consul] Enable trace analytics

Author: philip-iv

.gitignore

@@ -94,3 +94,6 @@ ENV/
 *.swp
 # IDEA
 .idea/
+
+# VS Code
+.vscode/

ddtrace/contrib/consul/patch.py

@@ -2,6 +2,8 @@
 
 from ddtrace.vendor.wrapt import wrap_function_wrapper as _w
 
+from ddtrace import config
+from ...constants import ANALYTICS_SAMPLE_RATE_KEY
 from ...ext import consul as consulx
 from ...pin import Pin
 from ...utils.wrappers import unwrap as _u
@@ -45,6 +47,9 @@ def trace_func(wrapped, instance, args, kwargs):
         resource = name.upper()
 
         with pin.tracer.trace(consulx.CMD, service=pin.service, resource=resource) as span:
+            rate = config.consul.get_analytics_sample_rate()
+            if rate is not None:
+                span.set_tag(ANALYTICS_SAMPLE_RATE_KEY, rate)
             span.set_tag(consulx.KEY, path)
             span.set_tag(consulx.CMD, resource)
             return wrapped(*args, **kwargs)

tests/contrib/consul/test.py

@@ -1,5 +1,6 @@
 import consul
 from ddtrace import Pin
+from ddtrace.constants import ANALYTICS_SAMPLE_RATE_KEY
 from ddtrace.ext import consul as consulx
 from ddtrace.vendor.wrapt import BoundFunctionWrapper
 from ddtrace.contrib.consul.patch import patch, unpatch
@@ -130,3 +131,39 @@ def test_patch_preserves_functionality(self):
         self.c.kv.delete(key)
         _, data = self.c.kv.get(key)
         assert data is None
+
+    def test_analytics_without_rate(self):
+        with self.override_config('consul', {'analytics_enabled': True}):
+            key = 'test/kwargs/consul'
+            value = 'test_value'
+
+            self.c.kv.put(key=key, value=value)
+
+            spans = self.get_spans()
+            assert len(spans) == 1
+            span = spans[0]
+            assert span.get_metric(ANALYTICS_SAMPLE_RATE_KEY) == 1.0
+
+    def test_analytics_with_rate(self):
+        with self.override_config('consul', {'analytics_enabled': True, 'analytics_sample_rate': 0.5}):
+            key = 'test/kwargs/consul'
+            value = 'test_value'
+
+            self.c.kv.put(key=key, value=value)
+
+            spans = self.get_spans()
+            assert len(spans) == 1
+            span = spans[0]
+            assert span.get_metric(ANALYTICS_SAMPLE_RATE_KEY) == 0.5
+
+    def test_analytics_disabled(self):
+        with self.override_config('consul', {'analytics_enabled': False}):
+            key = 'test/kwargs/consul'
+            value = 'test_value'
+
+            self.c.kv.put(key=key, value=value)
+
+            spans = self.get_spans()
+            assert len(spans) == 1
+            span = spans[0]
+            assert span.get_metric(ANALYTICS_SAMPLE_RATE_KEY) is None