[Backport-1.55] [WRR] Remove env var guard for WRR policy (#32946)

Backport of #32936

Co-authored-by: Mark D. Roth <roth@google.com>

doc/grpc_xds_features.md

@@ -70,3 +70,4 @@ Support for [xDS v2 APIs](https://www.envoyproxy.io/docs/envoy/latest/api/api_su
 [Outlier Detection](https://www.envoyproxy.io/docs/envoy/latest/intro/arch_overview/upstream/outlier):<br>Only the following detection types are supported:<ul><li>Success Rate</li><li>Failure Percentage</li></ul> | [A50](https://github.com/grpc/proposal/blob/master/A50-xds-outlier-detection.md) | v1.51.0 | v1.49.0 | v1.50.0 | v1.7.0 | |
 [Custom Load Balancer Configuration](https://github.com/envoyproxy/envoy/blob/57be3189ffa3372b34e9480d1f02b2d165e49077/api/envoy/config/cluster/v3/cluster.proto#L1208) | [A52](https://github.com/grpc/proposal/blob/master/A52-xds-custom-lb-policies.md) | v1.55.0 | v1.47.0 | | |
 [xDS Federation](https://github.com/cncf/xds/blob/main/proposals/TP1-xds-transport-next.md) | [A47](https://github.com/grpc/proposal/blob/master/A47-xds-federation.md) | v1.55.0 | | | |
+[Client-Side Weighted Round Robin LB Policy](https://github.com/envoyproxy/envoy/blob/a6d46b6ac4750720eec9a49abe701f0df9bf8e0a/api/envoy/extensions/load_balancing_policies/client_side_weighted_round_robin/v3/client_side_weighted_round_robin.proto#L36) | [A58](https://github.com/grpc/proposal/blob/master/A58-client-side-weighted-round-robin-lb-policy.md) | v1.55.0 | | | |

src/core/ext/filters/client_channel/lb_policy/weighted_round_robin/weighted_round_robin.cc

@@ -76,8 +76,7 @@ TraceFlag grpc_lb_wrr_trace(false, "weighted_round_robin_lb");
 
 namespace {
 
-constexpr absl::string_view kWeightedRoundRobin =
-    "weighted_round_robin_experimental";
+constexpr absl::string_view kWeightedRoundRobin = "weighted_round_robin";
 
 // Config for WRR policy.
 class WeightedRoundRobinConfig : public LoadBalancingPolicy::Config {

src/core/ext/xds/xds_lb_policy_registry.cc

@@ -35,8 +35,6 @@
 
 #include "src/core/ext/xds/xds_common_types.h"
 #include "src/core/lib/config/core_configuration.h"
-#include "src/core/lib/gpr/string.h"
-#include "src/core/lib/gprpp/env.h"
 #include "src/core/lib/gprpp/time.h"
 #include "src/core/lib/gprpp/validation_errors.h"
 #include "src/core/lib/load_balancing/lb_policy_registry.h"
@@ -137,8 +135,7 @@ class ClientSideWeightedRoundRobinLbPolicyConfigFactory
       }
       config["errorUtilizationPenalty"] = value;
     }
-    return Json::Object{
-        {"weighted_round_robin_experimental", std::move(config)}};
+    return Json::Object{{"weighted_round_robin", std::move(config)}};
   }
 
   absl::string_view type() override { return Type(); }
@@ -258,31 +255,16 @@ class WrrLocalityLbPolicyConfigFactory
 // XdsLbPolicyRegistry
 //
 
-namespace {
-
-// TODO(roth): Remove this when interop tests pass.
-bool XdsWrrLbEnabled() {
-  auto value = GetEnv("GRPC_EXPERIMENTAL_XDS_WRR_LB");
-  if (!value.has_value()) return false;
-  bool parsed_value;
-  bool parse_succeeded = gpr_parse_bool_value(value->c_str(), &parsed_value);
-  return parse_succeeded && parsed_value;
-}
-
-}  // namespace
-
 XdsLbPolicyRegistry::XdsLbPolicyRegistry() {
   policy_config_factories_.emplace(
       RingHashLbPolicyConfigFactory::Type(),
       std::make_unique<RingHashLbPolicyConfigFactory>());
   policy_config_factories_.emplace(
       RoundRobinLbPolicyConfigFactory::Type(),
       std::make_unique<RoundRobinLbPolicyConfigFactory>());
-  if (XdsWrrLbEnabled()) {
-    policy_config_factories_.emplace(
-        ClientSideWeightedRoundRobinLbPolicyConfigFactory::Type(),
-        std::make_unique<ClientSideWeightedRoundRobinLbPolicyConfigFactory>());
-  }
+  policy_config_factories_.emplace(
+      ClientSideWeightedRoundRobinLbPolicyConfigFactory::Type(),
+      std::make_unique<ClientSideWeightedRoundRobinLbPolicyConfigFactory>());
   policy_config_factories_.emplace(
       WrrLocalityLbPolicyConfigFactory::Type(),
       std::make_unique<WrrLocalityLbPolicyConfigFactory>());

test/core/client_channel/lb_policy/weighted_round_robin_config_test.cc

@@ -34,7 +34,7 @@ TEST(WeightedRoundRobinConfigTest, EmptyConfig) {
   const char* service_config_json =
       "{\n"
       "  \"loadBalancingConfig\":[{\n"
-      "    \"weighted_round_robin_experimental\":{\n"
+      "    \"weighted_round_robin\":{\n"
       "    }\n"
       "  }]\n"
       "}\n";
@@ -48,7 +48,7 @@ TEST(WeightedRoundRobinConfigTest, InvalidTypes) {
   const char* service_config_json =
       "{\n"
       "  \"loadBalancingConfig\":[{\n"
-      "    \"weighted_round_robin_experimental\":{\n"
+      "    \"weighted_round_robin\":{\n"
       "      \"enableOobLoadReport\": 5,\n"
       "      \"oobReportingPeriod\": true,\n"
       "      \"blackoutPeriod\": [],\n"
@@ -78,7 +78,7 @@ TEST(WeightedRoundRobinConfigTest, InvalidValues) {
   const char* service_config_json =
       "{\n"
       "  \"loadBalancingConfig\":[{\n"
-      "    \"weighted_round_robin_experimental\":{\n"
+      "    \"weighted_round_robin\":{\n"
       "      \"errorUtilizationPenalty\": -1.0\n"
       "    }\n"
       "  }]\n"

test/core/client_channel/lb_policy/weighted_round_robin_test.cc

@@ -106,8 +106,7 @@ class WeightedRoundRobinTest : public LoadBalancingPolicyTest {
     }
 
     RefCountedPtr<LoadBalancingPolicy::Config> Build() {
-      Json config = Json::Array{
-          Json::Object{{"weighted_round_robin_experimental", json_}}};
+      Json config = Json::Array{Json::Object{{"weighted_round_robin", json_}}};
       gpr_log(GPR_INFO, "CONFIG: %s", JsonDump(config).c_str());
       return MakeConfig(config);
     }
@@ -155,7 +154,7 @@ class WeightedRoundRobinTest : public LoadBalancingPolicyTest {
       return true;
     };
     ON_CALL(*mock_ee_, Cancel(::testing::_)).WillByDefault(cancel);
-    lb_policy_ = MakeLbPolicy("weighted_round_robin_experimental");
+    lb_policy_ = MakeLbPolicy("weighted_round_robin");
   }
 
   ~WeightedRoundRobinTest() override {

test/core/xds/BUILD

@@ -122,7 +122,6 @@ grpc_cc_test(
         "//src/proto/grpc/testing/xds/v3:udpa_typed_struct_proto",
         "//src/proto/grpc/testing/xds/v3:wrr_locality_proto",
         "//test/core/util:grpc_test_util",
-        "//test/core/util:scoped_env_var",
         "//test/cpp/util:grpc_cli_utils",
     ],
 )

test/core/xds/xds_lb_policy_registry_test.cc

@@ -52,7 +52,6 @@
 #include "src/proto/grpc/testing/xds/v3/round_robin.pb.h"
 #include "src/proto/grpc/testing/xds/v3/typed_struct.pb.h"
 #include "src/proto/grpc/testing/xds/v3/wrr_locality.pb.h"
-#include "test/core/util/scoped_env_var.h"
 #include "test/core/util/test_config.h"
 
 namespace grpc_core {
@@ -131,19 +130,17 @@ TEST(RoundRobin, Basic) {
 //
 
 TEST(ClientSideWeightedRoundRobinTest, DefaultConfig) {
-  ScopedExperimentalEnvVar env_var("GRPC_EXPERIMENTAL_XDS_WRR_LB");
   LoadBalancingPolicyProto policy;
   policy.add_policies()
       ->mutable_typed_extension_config()
       ->mutable_typed_config()
       ->PackFrom(ClientSideWeightedRoundRobin());
   auto result = ConvertXdsPolicy(policy);
   ASSERT_TRUE(result.ok()) << result.status();
-  EXPECT_EQ(*result, "{\"weighted_round_robin_experimental\":{}}");
+  EXPECT_EQ(*result, "{\"weighted_round_robin\":{}}");
 }
 
 TEST(ClientSideWeightedRoundRobinTest, FieldsExplicitlySet) {
-  ScopedExperimentalEnvVar env_var("GRPC_EXPERIMENTAL_XDS_WRR_LB");
   ClientSideWeightedRoundRobin wrr;
   wrr.mutable_enable_oob_load_report()->set_value(true);
   wrr.mutable_oob_reporting_period()->set_seconds(1);
@@ -159,7 +156,7 @@ TEST(ClientSideWeightedRoundRobinTest, FieldsExplicitlySet) {
   auto result = ConvertXdsPolicy(policy);
   ASSERT_TRUE(result.ok()) << result.status();
   EXPECT_EQ(*result,
-            "{\"weighted_round_robin_experimental\":{"
+            "{\"weighted_round_robin\":{"
             "\"blackoutPeriod\":\"2.000000000s\","
             "\"enableOobLoadReport\":true,"
             "\"errorUtilizationPenalty\":5.000000,"
@@ -170,7 +167,6 @@ TEST(ClientSideWeightedRoundRobinTest, FieldsExplicitlySet) {
 }
 
 TEST(ClientSideWeightedRoundRobinTest, InvalidValues) {
-  ScopedExperimentalEnvVar env_var("GRPC_EXPERIMENTAL_XDS_WRR_LB");
   ClientSideWeightedRoundRobin wrr;
   wrr.mutable_oob_reporting_period()->set_seconds(-1);
   wrr.mutable_blackout_period()->set_seconds(-2);
@@ -213,20 +209,6 @@ TEST(ClientSideWeightedRoundRobinTest, InvalidValues) {
       << result.status();
 }
 
-TEST(ClientSideWeightedRoundRobinTest, EnvVarNotEnabled) {
-  LoadBalancingPolicyProto policy;
-  policy.add_policies()
-      ->mutable_typed_extension_config()
-      ->mutable_typed_config()
-      ->PackFrom(ClientSideWeightedRoundRobin());
-  auto result = ConvertXdsPolicy(policy);
-  EXPECT_EQ(result.status().code(), absl::StatusCode::kInvalidArgument);
-  EXPECT_EQ(result.status().message(),
-            "validation errors: [field:load_balancing_policy "
-            "error:no supported load balancing policy config found]")
-      << result.status();
-}
-
 //
 // RingHash
 //

test/cpp/end2end/client_lb_end2end_test.cc

@@ -3060,7 +3060,7 @@ TEST_F(ControlPlaneStatusRewritingTest, RewritesFromConfigSelector) {
 const char kServiceConfigPerCall[] =
     "{\n"
     "  \"loadBalancingConfig\": [\n"
-    "    {\"weighted_round_robin_experimental\": {\n"
+    "    {\"weighted_round_robin\": {\n"
     "      \"blackoutPeriod\": \"0s\",\n"
     "      \"weightUpdatePeriod\": \"0.1s\"\n"
     "    }}\n"
@@ -3070,7 +3070,7 @@ const char kServiceConfigPerCall[] =
 const char kServiceConfigOob[] =
     "{\n"
     "  \"loadBalancingConfig\": [\n"
-    "    {\"weighted_round_robin_experimental\": {\n"
+    "    {\"weighted_round_robin\": {\n"
     "      \"blackoutPeriod\": \"0s\",\n"
     "      \"weightUpdatePeriod\": \"0.1s\",\n"
     "      \"enableOobLoadReport\": true\n"
@@ -3155,8 +3155,7 @@ TEST_F(WeightedRoundRobinTest, CallAndServerMetric) {
   ExpectWeightedRoundRobinPicks(DEBUG_LOCATION, stub,
                                 /*expected_weights=*/{1, 2, 4});
   // Check LB policy name for the channel.
-  EXPECT_EQ("weighted_round_robin_experimental",
-            channel->GetLoadBalancingPolicyName());
+  EXPECT_EQ("weighted_round_robin", channel->GetLoadBalancingPolicyName());
 }
 
 class WeightedRoundRobinParamTest
@@ -3191,8 +3190,7 @@ TEST_P(WeightedRoundRobinParamTest, Basic) {
   ExpectWeightedRoundRobinPicks(DEBUG_LOCATION, stub,
                                 /*expected_weights=*/{1, 2, 4});
   // Check LB policy name for the channel.
-  EXPECT_EQ("weighted_round_robin_experimental",
-            channel->GetLoadBalancingPolicyName());
+  EXPECT_EQ("weighted_round_robin", channel->GetLoadBalancingPolicyName());
 }
 
 }  // namespace