Merge pull request #102 from bianpengyuan/random-sampling

fix random sample fraction percent

Author: rlenglet

source/extensions/filters/network/http_connection_manager/config.cc

@@ -266,8 +266,9 @@ HttpConnectionManagerConfig::HttpConnectionManagerConfig(
     envoy::type::FractionalPercent random_sampling;
     // TODO: Random sampling historically was an integer and default to out of 10,000. We should
     // deprecate that and move to a straight fractional percent config.
-    random_sampling.set_numerator(
-        tracing_config.has_random_sampling() ? tracing_config.random_sampling().value() : 10000);
+    uint64_t random_sampling_numerator{PROTOBUF_PERCENT_TO_ROUNDED_INTEGER_OR_DEFAULT(
+      tracing_config, random_sampling, 10000, 10000)};
+    random_sampling.set_numerator(random_sampling_numerator);
     random_sampling.set_denominator(envoy::type::FractionalPercent::TEN_THOUSAND);
     envoy::type::FractionalPercent overall_sampling;
     overall_sampling.set_numerator(

test/extensions/filters/network/http_connection_manager/config_test.cc

@@ -294,14 +294,48 @@ TEST_F(HttpConnectionManagerConfigTest, SamplingConfigured) {
   EXPECT_EQ(1, config.tracingConfig()->client_sampling_.numerator());
   EXPECT_EQ(envoy::type::FractionalPercent::HUNDRED,
             config.tracingConfig()->client_sampling_.denominator());
-  EXPECT_EQ(2, config.tracingConfig()->random_sampling_.numerator());
+  EXPECT_EQ(200, config.tracingConfig()->random_sampling_.numerator());
   EXPECT_EQ(envoy::type::FractionalPercent::TEN_THOUSAND,
             config.tracingConfig()->random_sampling_.denominator());
   EXPECT_EQ(3, config.tracingConfig()->overall_sampling_.numerator());
   EXPECT_EQ(envoy::type::FractionalPercent::HUNDRED,
             config.tracingConfig()->overall_sampling_.denominator());
 }
 
+TEST_F(HttpConnectionManagerConfigTest, FractionalSamplingConfigured) {
+  const std::string yaml_string = R"EOF(
+  stat_prefix: ingress_http
+  internal_address_config:
+    unix_sockets: true
+  route_config:
+    name: local_route
+  tracing:
+    operation_name: ingress
+    client_sampling:
+      value: 0.1
+    random_sampling:
+      value: 0.2
+    overall_sampling:
+      value: 0.3
+  http_filters:
+  - name: envoy.router
+  )EOF";
+
+  HttpConnectionManagerConfig config(parseHttpConnectionManagerFromV2Yaml(yaml_string), context_,
+                                     date_provider_, route_config_provider_manager_,
+                                     scoped_routes_config_provider_manager_);
+
+  EXPECT_EQ(0, config.tracingConfig()->client_sampling_.numerator());
+  EXPECT_EQ(envoy::type::FractionalPercent::HUNDRED,
+            config.tracingConfig()->client_sampling_.denominator());
+  EXPECT_EQ(20, config.tracingConfig()->random_sampling_.numerator());
+  EXPECT_EQ(envoy::type::FractionalPercent::TEN_THOUSAND,
+            config.tracingConfig()->random_sampling_.denominator());
+  EXPECT_EQ(0, config.tracingConfig()->overall_sampling_.numerator());
+  EXPECT_EQ(envoy::type::FractionalPercent::HUNDRED,
+            config.tracingConfig()->overall_sampling_.denominator());
+}
+
 TEST_F(HttpConnectionManagerConfigTest, UnixSocketInternalAddress) {
   const std::string yaml_string = R"EOF(
   stat_prefix: ingress_http