Add test for explicit option

include/grpc++/ext/health_check_service_server_builder_option.h

@@ -47,7 +47,7 @@ class HealthCheckServiceServerBuilderOption : public ServerBuilderOption {
   // Use nullptr to disable default service.
   explicit HealthCheckServiceServerBuilderOption(
       std::unique_ptr<HealthCheckServiceInterface> hc);
-  ~HealthCheckServiceServerBuilderOption() {}
+  ~HealthCheckServiceServerBuilderOption() override {}
   void UpdateArguments(ChannelArguments* args) override;
   void UpdatePlugins(std::vector<std::unique_ptr<ServerBuilderPlugin>>* plugins) override;
  private:

src/cpp/server/health/default_health_check_service.cc

@@ -35,6 +35,7 @@
 #include <mutex>
 
 #include <grpc++/impl/codegen/method_handler_impl.h>
+#include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 
 #include "src/cpp/server/health/default_health_check_service.h"
@@ -65,18 +66,18 @@ Status DefaultHealthCheckService::SyncHealthCheckServiceImpl::Check(
   // Decode request.
   std::vector<Slice> slices;
   request->Dump(&slices);
-  const uint8_t* request_bytes = nullptr;
+  uint8_t* request_bytes = nullptr;
   bool request_bytes_owned = false;
   size_t request_size = 0;
   grpc_health_v1_HealthCheckRequest request_struct;
   if (slices.empty()) {
     request_struct.has_service = false;
   } else if (slices.size() == 1) {
-    request_bytes = slices[0].begin();
+    request_bytes = const_cast<uint8_t*>(slices[0].begin());
     request_size = slices[0].size();
   } else {
     request_bytes_owned = true;
-    request_bytes = gpr_malloc(request->Length());
+    request_bytes = static_cast<uint8_t*>(gpr_malloc(request->Length()));
     uint8_t* copy_to = request_bytes;
     for (size_t i = 0; i < slices.size(); i++) {
       memcpy(copy_to, slices[i].begin(), slices[i].size());

test/cpp/end2end/health_service_end2end_test.cc

@@ -32,11 +32,14 @@
  */
 
 #include <memory>
+#include <mutex>
 #include <thread>
+#include <vector>
 
 #include <grpc++/channel.h>
 #include <grpc++/client_context.h>
 #include <grpc++/create_channel.h>
+#include <grpc++/ext/health_check_service_server_builder_option.h>
 #include <grpc++/health_check_service_interface.h>
 #include <grpc++/server.h>
 #include <grpc++/server_builder.h>
@@ -59,20 +62,92 @@ namespace grpc {
 namespace testing {
 namespace {
 
+// A sample sync implementation of the health checking service. This does the
+// same thing as the default one.
+class HealthCheckServiceImpl : public ::grpc::health::v1::Health::Service {
+ public:
+  Status Check(ServerContext* context, const HealthCheckRequest* request,
+               HealthCheckResponse* response) override {
+    std::lock_guard<std::mutex> lock(mu_);
+    auto iter = status_map_.find(request->service());
+    if (iter == status_map_.end()) {
+      return Status(StatusCode::NOT_FOUND, "");
+    }
+    response->set_status(iter->second);
+    return Status::OK;
+  }
+
+  void SetStatus(const grpc::string& service_name,
+                 HealthCheckResponse::ServingStatus status) {
+    std::lock_guard<std::mutex> lock(mu_);
+    status_map_[service_name] = status;
+  }
+
+  void SetAll(HealthCheckResponse::ServingStatus status) {
+    std::lock_guard<std::mutex> lock(mu_);
+    for (auto iter = status_map_.begin(); iter != status_map_.end(); ++iter) {
+      iter->second = status;
+    }
+  }
+
+ private:
+  std::mutex mu_;
+  std::map<const grpc::string, HealthCheckResponse::ServingStatus> status_map_;
+};
+
+// A custom implementation of the health checking service interface. This is
+// used to test that it prevents the server from creating a default service and
+// also serves as an example of how to override the default service.
+class CustomHealthCheckService : public HealthCheckServiceInterface {
+ public:
+  explicit CustomHealthCheckService(HealthCheckServiceImpl* impl)
+      : impl_(impl) {
+    impl_->SetStatus("", HealthCheckResponse::SERVING);
+  }
+  void SetServingStatus(const grpc::string& service_name,
+                        bool serving) override {
+    impl_->SetStatus(service_name, serving ? HealthCheckResponse::SERVING
+                                           : HealthCheckResponse::NOT_SERVING);
+  }
+
+  void SetServingStatus(bool serving) override {
+    impl_->SetAll(serving ? HealthCheckResponse::SERVING
+                          : HealthCheckResponse::NOT_SERVING);
+  }
+
+ private:
+  HealthCheckServiceImpl* impl_;  // not owned
+};
+
 class HealthServiceEnd2endTest : public ::testing::Test {
  protected:
   HealthServiceEnd2endTest() {}
 
-  void SetUpServer(grpc::Service* explicit_health_service) {
+  void SetUpServer(bool register_sync_test_service,
+                   bool explicit_health_service,
+                   std::unique_ptr<HealthCheckServiceInterface> service) {
     int port = grpc_pick_unused_port_or_die();
     server_address_ << "localhost:" << port;
 
+    bool register_sync_health_service_impl =
+        explicit_health_service && service != nullptr;
+
     // Setup server
     ServerBuilder builder;
+    if (explicit_health_service) {
+      std::unique_ptr<ServerBuilderOption> option(
+          new HealthCheckServiceServerBuilderOption(std::move(service)));
+      builder.SetOption(std::move(option));
+    }
     builder.AddListeningPort(server_address_.str(),
                              grpc::InsecureServerCredentials());
-    // Register a sync service.
-    builder.RegisterService(&echo_test_service_);
+    if (register_sync_test_service) {
+      // Register a sync service.
+      builder.RegisterService(&echo_test_service_);
+    }
+    if (register_sync_health_service_impl) {
+      builder.RegisterService(&health_check_service_impl_);
+    }
     server_ = builder.BuildAndStart();
   }
 
@@ -88,6 +163,14 @@ class HealthServiceEnd2endTest : public ::testing::Test {
     hc_stub_ = grpc::health::v1::Health::NewStub(channel);
   }
 
+  // When the expected_status is NOT OK, we do not care about the response.
+  void SendHealthCheckRpc(const grpc::string& service_name,
+                          const Status& expected_status) {
+    EXPECT_FALSE(expected_status.ok());
+    SendHealthCheckRpc(service_name, expected_status,
+                       HealthCheckResponse::UNKNOWN);
+  }
+
   void SendHealthCheckRpc(
       const grpc::string& service_name, const Status& expected_status,
       HealthCheckResponse::ServingStatus expected_serving_status) {
@@ -102,7 +185,37 @@ class HealthServiceEnd2endTest : public ::testing::Test {
     }
   }
 
+  void VerifyHealthCheckService() {
+    HealthCheckServiceInterface* service = server_->GetHealthCheckService();
+    EXPECT_TRUE(service != nullptr);
+    const grpc::string kHealthyService("healthy_service");
+    const grpc::string kUnhealthyService("unhealthy_service");
+    const grpc::string kNotRegisteredService("not_registered");
+    service->SetServingStatus(kHealthyService, true);
+    service->SetServingStatus(kUnhealthyService, false);
+
+    ResetStubs();
+
+    SendHealthCheckRpc("", Status::OK, HealthCheckResponse::SERVING);
+    SendHealthCheckRpc(kHealthyService, Status::OK,
+                       HealthCheckResponse::SERVING);
+    SendHealthCheckRpc(kUnhealthyService, Status::OK,
+                       HealthCheckResponse::NOT_SERVING);
+    SendHealthCheckRpc(kNotRegisteredService,
+                       Status(StatusCode::NOT_FOUND, ""));
+
+    service->SetServingStatus(false);
+    SendHealthCheckRpc("", Status::OK, HealthCheckResponse::NOT_SERVING);
+    SendHealthCheckRpc(kHealthyService, Status::OK,
+                       HealthCheckResponse::NOT_SERVING);
+    SendHealthCheckRpc(kUnhealthyService, Status::OK,
+                       HealthCheckResponse::NOT_SERVING);
+    SendHealthCheckRpc(kNotRegisteredService,
+                       Status(StatusCode::NOT_FOUND, ""));
+  }
+
   TestServiceImpl echo_test_service_;
+  HealthCheckServiceImpl health_check_service_impl_;
   std::unique_ptr<Health::Stub> hc_stub_;
   std::unique_ptr<Server> server_;
   std::ostringstream server_address_;
@@ -111,47 +224,56 @@ class HealthServiceEnd2endTest : public ::testing::Test {
 TEST_F(HealthServiceEnd2endTest, DefaultHealthServiceDisabled) {
   EnableDefaultHealthCheckService(false);
   EXPECT_FALSE(DefaultHealthCheckServiceEnabled());
-  SetUpServer(nullptr);
+  SetUpServer(true, false, nullptr);
   HealthCheckServiceInterface* default_service =
       server_->GetHealthCheckService();
   EXPECT_TRUE(default_service == nullptr);
+
+  ResetStubs();
+
+  SendHealthCheckRpc("", Status(StatusCode::UNIMPLEMENTED, ""));
 }
 
 TEST_F(HealthServiceEnd2endTest, DefaultHealthService) {
   EnableDefaultHealthCheckService(true);
   EXPECT_TRUE(DefaultHealthCheckServiceEnabled());
-  SetUpServer(nullptr);
-  HealthCheckServiceInterface* default_service =
-      server_->GetHealthCheckService();
-  EXPECT_TRUE(default_service != nullptr);
-  const grpc::string kHealthyService("healthy_service");
-  const grpc::string kUnhealthyService("unhealthy_service");
-  const grpc::string kNotRegisteredService("not_registered");
+  SetUpServer(true, false, nullptr);
+  VerifyHealthCheckService();
+
+  // The default service has a size limit of the service name.
   const grpc::string kTooLongServiceName(201, 'x');
-  default_service->SetServingStatus(kHealthyService, true);
-  default_service->SetServingStatus(kUnhealthyService, false);
+  SendHealthCheckRpc(kTooLongServiceName,
+                     Status(StatusCode::INVALID_ARGUMENT, ""));
+}
+
+// Provide an empty service to disable the default service.
+TEST_F(HealthServiceEnd2endTest, ExplicitlyDisableViaOverride) {
+  EnableDefaultHealthCheckService(true);
+  EXPECT_TRUE(DefaultHealthCheckServiceEnabled());
+  std::unique_ptr<HealthCheckServiceInterface> empty_service;
+  SetUpServer(true, true, std::move(empty_service));
+  HealthCheckServiceInterface* service = server_->GetHealthCheckService();
+  EXPECT_TRUE(service == nullptr);
+
+  ResetStubs();
+
+  SendHealthCheckRpc("", Status(StatusCode::UNIMPLEMENTED, ""));
+}
+
+// Provide an explicit override of health checking service interface.
+TEST_F(HealthServiceEnd2endTest, ExplicitlyOverride) {
+  EnableDefaultHealthCheckService(true);
+  EXPECT_TRUE(DefaultHealthCheckServiceEnabled());
+  std::unique_ptr<HealthCheckServiceInterface> override_service(
+      new CustomHealthCheckService(&health_check_service_impl_));
+  HealthCheckServiceInterface* underlying_service = override_service.get();
+  SetUpServer(false, true, std::move(override_service));
+  HealthCheckServiceInterface* service = server_->GetHealthCheckService();
+  EXPECT_TRUE(service == underlying_service);
 
   ResetStubs();
 
-  SendHealthCheckRpc("", Status::OK, HealthCheckResponse::SERVING);
-  SendHealthCheckRpc(kHealthyService, Status::OK, HealthCheckResponse::SERVING);
-  SendHealthCheckRpc(kUnhealthyService, Status::OK,
-                     HealthCheckResponse::NOT_SERVING);
-  SendHealthCheckRpc(kNotRegisteredService, Status(StatusCode::NOT_FOUND, ""),
-                     HealthCheckResponse::NOT_SERVING);
-  SendHealthCheckRpc(kTooLongServiceName, Status(StatusCode::INVALID_ARGUMENT, ""),
-                     HealthCheckResponse::NOT_SERVING);
-
-  default_service->SetServingStatus(false);
-  SendHealthCheckRpc("", Status::OK, HealthCheckResponse::NOT_SERVING);
-  SendHealthCheckRpc(kHealthyService, Status::OK,
-                     HealthCheckResponse::NOT_SERVING);
-  SendHealthCheckRpc(kUnhealthyService, Status::OK,
-                     HealthCheckResponse::NOT_SERVING);
-  SendHealthCheckRpc(kNotRegisteredService, Status(StatusCode::NOT_FOUND, ""),
-                     HealthCheckResponse::NOT_SERVING);
-  SendHealthCheckRpc(kTooLongServiceName, Status(StatusCode::INVALID_ARGUMENT, ""),
-                     HealthCheckResponse::NOT_SERVING);
+  VerifyHealthCheckService();
 }
 
 }  // namespace