dlb: optimize auto detect logic

contrib/network/connection_balance/dlb/source/connection_balancer_impl.cc

@@ -40,25 +40,21 @@ DlbConnectionBalanceFactory::createConnectionBalancerFromProto(
 #ifdef DLB_DISABLED
   throw EnvoyException("X86_64 architecture is required for Dlb.");
 #else
-  int device_id = 0;
+  int device_id = dlb_config.id();
   Api::OsSysCalls& os_sys_calls = Api::OsSysCallsSingleton::get();
   struct stat buffer;
 
-  if (dlb_config.id()) {
-    device_id = dlb_config.id();
-    const std::string& device_name = fmt::format("/dev/dlb{}", device_id);
-    if (os_sys_calls.stat(device_name.c_str(), &buffer).return_value_ != 0) {
-      ExceptionUtil::throwEnvoyException(fmt::format("dlb hardware {} not found", device_name));
-    }
-  } else {
-    std::string device_name;
+  std::string device_name = fmt::format("/dev/dlb{}", device_id);
+  if (os_sys_calls.stat(device_name.c_str(), &buffer).return_value_ != 0) {
     int i = 0;
     // auto detect available dlb devices, now the max number of dlb device id is 63.
     const int max_id = 64;
     for (; i < max_id; i++) {
       device_name = fmt::format("/dev/dlb{}", i);
       if (os_sys_calls.stat(device_name.c_str(), &buffer).return_value_ == 0) {
         device_id = i;
+        ENVOY_LOG(warn, "dlb device {} is not found, use dlb device {} instead", dlb_config.id(),
+                  device_id);
         break;
       }
     }
@@ -239,6 +235,8 @@ DlbConnectionBalanceFactory::~DlbConnectionBalanceFactory() {
   }
 }
 
+REGISTER_FACTORY(DlbConnectionBalanceFactory, Envoy::Network::ConnectionBalanceFactory);
+
 void DlbBalancedConnectionHandlerImpl::setDlbEvent() {
   auto listener = dynamic_cast<Envoy::Server::ActiveTcpListener*>(&handler_);
 

contrib/network/connection_balance/dlb/source/connection_balancer_impl.h

@@ -127,7 +127,6 @@ class DlbConnectionBalanceFactory : public Envoy::Network::ConnectionBalanceFact
 #endif
 };
 
-REGISTER_FACTORY(DlbConnectionBalanceFactory, Envoy::Network::ConnectionBalanceFactory);
 using DlbConnectionBalanceFactorySingleton = InjectableSingleton<DlbConnectionBalanceFactory>;
 
 /**

contrib/network/connection_balance/dlb/test/BUILD

@@ -12,9 +12,10 @@ envoy_cc_test(
     name = "config_test",
     srcs = ["config_test.cc"],
     deps = [
+        "//contrib/network/connection_balance/dlb/source:connection_balancer",
         "//source/common/protobuf:utility_lib",
+        "//test/mocks/server:factory_context_mocks",
         "//test/test_common:status_utility_lib",
-        "@envoy_api//contrib/envoy/extensions/network/connection_balance/dlb/v3alpha:pkg_cc_proto",
         "@envoy_api//envoy/config/core/v3:pkg_cc_proto",
     ],
 )

contrib/network/connection_balance/dlb/test/config_test.cc

@@ -2,9 +2,10 @@
 
 #include "source/common/protobuf/utility.h"
 
+#include "test/mocks/server/factory_context.h"
 #include "test/test_common/status_utility.h"
 
-#include "contrib/envoy/extensions/network/connection_balance/dlb/v3alpha/dlb.pb.h"
+#include "contrib/network/connection_balance/dlb/source/connection_balancer_impl.h"
 #include "gtest/gtest.h"
 
 namespace Envoy {
@@ -52,6 +53,44 @@ TEST_F(DlbConnectionBalanceFactoryTest, MakeCustomConfig) {
   EXPECT_EQ(10, dlb.id());
 }
 
+TEST_F(DlbConnectionBalanceFactoryTest, EmptyProto) {
+  DlbConnectionBalanceFactory factory;
+  EXPECT_NE(nullptr,
+            dynamic_cast<envoy::extensions::network::connection_balance::dlb::v3alpha::Dlb*>(
+                factory.createEmptyConfigProto().get()));
+}
+
+#ifndef DLB_DISABLED
+
+using testing::HasSubstr;
+
+TEST_F(DlbConnectionBalanceFactoryTest, MakeFromDefaultProto) {
+  envoy::config::core::v3::TypedExtensionConfig typed_config;
+  DlbConnectionBalanceFactory factory;
+  NiceMock<Server::Configuration::MockFactoryContext> context;
+
+  envoy::extensions::network::connection_balance::dlb::v3alpha::Dlb dlb;
+  makeDlbConnectionBalanceConfig(typed_config, dlb);
+
+  EXPECT_THAT_THROWS_MESSAGE(factory.createConnectionBalancerFromProto(typed_config, context),
+                             EnvoyException, HasSubstr("no available dlb hardware"));
+}
+
+TEST_F(DlbConnectionBalanceFactoryTest, TooManyThreads) {
+  envoy::config::core::v3::TypedExtensionConfig typed_config;
+  DlbConnectionBalanceFactory factory;
+  NiceMock<Server::Configuration::MockFactoryContext> context;
+  context.options_.concurrency_ = 33;
+
+  envoy::extensions::network::connection_balance::dlb::v3alpha::Dlb dlb;
+  makeDlbConnectionBalanceConfig(typed_config, dlb);
+
+  EXPECT_THAT_THROWS_MESSAGE(
+      factory.createConnectionBalancerFromProto(typed_config, context), EnvoyException,
+      HasSubstr("Dlb connection balanncer only supports up to 32 worker threads"));
+}
+#endif
+
 } // namespace Dlb
 } // namespace Extensions
 } // namespace Envoy