/* * * Copyright 2015 gRPC authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * */ #ifndef GRPCPP_IMPL_CODEGEN_SERVER_INTERFACE_H #define GRPCPP_IMPL_CODEGEN_SERVER_INTERFACE_H #include #include #include #include #include #include namespace grpc { class AsyncGenericService; class Channel; class GenericServerContext; class ServerCompletionQueue; class ServerContext; class ServerCredentials; class Service; extern CoreCodegenInterface* g_core_codegen_interface; /// Models a gRPC server. /// /// Servers are configured and started via \a grpc::ServerBuilder. namespace internal { class ServerAsyncStreamingInterface; } // namespace internal class ServerInterface : public internal::CallHook { public: virtual ~ServerInterface() {} /// \a Shutdown does the following things: /// /// 1. Shutdown the server: deactivate all listening ports, mark it in /// "shutdown mode" so that further call Request's or incoming RPC matches /// are no longer allowed. Also return all Request'ed-but-not-yet-active /// calls as failed (!ok). This refers to calls that have been requested /// at the server by the server-side library or application code but that /// have not yet been matched to incoming RPCs from the client. Note that /// this would even include default calls added automatically by the gRPC /// C++ API without the user's input (e.g., "Unimplemented RPC method") /// /// 2. Block until all rpc method handlers invoked automatically by the sync /// API finish. /// /// 3. If all pending calls complete (and all their operations are /// retrieved by Next) before \a deadline expires, this finishes /// gracefully. Otherwise, forcefully cancel all pending calls associated /// with the server after \a deadline expires. In the case of the sync API, /// if the RPC function for a streaming call has already been started and /// takes a week to complete, the RPC function won't be forcefully /// terminated (since that would leave state corrupt and incomplete) and /// the method handler will just keep running (which will prevent the /// server from completing the "join" operation that it needs to do at /// shutdown time). /// /// All completion queue associated with the server (for example, for async /// serving) must be shutdown *after* this method has returned: /// See \a ServerBuilder::AddCompletionQueue for details. /// They must also be drained (by repeated Next) after being shutdown. /// /// \param deadline How long to wait until pending rpcs are forcefully /// terminated. template void Shutdown(const T& deadline) { ShutdownInternal(TimePoint(deadline).raw_time()); } /// Shutdown the server without a deadline and forced cancellation. /// /// All completion queue associated with the server (for example, for async /// serving) must be shutdown *after* this method has returned: /// See \a ServerBuilder::AddCompletionQueue for details. void Shutdown() { ShutdownInternal( g_core_codegen_interface->gpr_inf_future(GPR_CLOCK_MONOTONIC)); } /// Block waiting for all work to complete. /// /// \warning The server must be either shutting down or some other thread must /// call \a Shutdown for this function to ever return. virtual void Wait() = 0; protected: friend class ::grpc::Service; /// Register a service. This call does not take ownership of the service. /// The service must exist for the lifetime of the Server instance. virtual bool RegisterService(const grpc::string* host, Service* service) = 0; /// Register a generic service. This call does not take ownership of the /// service. The service must exist for the lifetime of the Server instance. virtual void RegisterAsyncGenericService(AsyncGenericService* service) = 0; /// Tries to bind \a server to the given \a addr. /// /// It can be invoked multiple times. /// /// \param addr The address to try to bind to the server (eg, localhost:1234, /// 192.168.1.1:31416, [::1]:27182, etc.). /// \params creds The credentials associated with the server. /// /// \return bound port number on sucess, 0 on failure. /// /// \warning It's an error to call this method on an already started server. virtual int AddListeningPort(const grpc::string& addr, ServerCredentials* creds) = 0; /// Start the server. /// /// \param cqs Completion queues for handling asynchronous services. The /// caller is required to keep all completion queues live until the server is /// destroyed. /// \param num_cqs How many completion queues does \a cqs hold. virtual void Start(ServerCompletionQueue** cqs, size_t num_cqs) = 0; virtual void ShutdownInternal(gpr_timespec deadline) = 0; virtual int max_receive_message_size() const = 0; virtual grpc_server* server() = 0; virtual void PerformOpsOnCall(internal::CallOpSetInterface* ops, internal::Call* call) = 0; class BaseAsyncRequest : public internal::CompletionQueueTag { public: BaseAsyncRequest(ServerInterface* server, ServerContext* context, internal::ServerAsyncStreamingInterface* stream, CompletionQueue* call_cq, void* tag, bool delete_on_finalize); virtual ~BaseAsyncRequest(); bool FinalizeResult(void** tag, bool* status) override; protected: ServerInterface* const server_; ServerContext* const context_; internal::ServerAsyncStreamingInterface* const stream_; CompletionQueue* const call_cq_; void* const tag_; const bool delete_on_finalize_; grpc_call* call_; }; class RegisteredAsyncRequest : public BaseAsyncRequest { public: RegisteredAsyncRequest(ServerInterface* server, ServerContext* context, internal::ServerAsyncStreamingInterface* stream, CompletionQueue* call_cq, void* tag); // uses BaseAsyncRequest::FinalizeResult protected: void IssueRequest(void* registered_method, grpc_byte_buffer** payload, ServerCompletionQueue* notification_cq); }; class NoPayloadAsyncRequest final : public RegisteredAsyncRequest { public: NoPayloadAsyncRequest(void* registered_method, ServerInterface* server, ServerContext* context, internal::ServerAsyncStreamingInterface* stream, CompletionQueue* call_cq, ServerCompletionQueue* notification_cq, void* tag) : RegisteredAsyncRequest(server, context, stream, call_cq, tag) { IssueRequest(registered_method, nullptr, notification_cq); } // uses RegisteredAsyncRequest::FinalizeResult }; template class PayloadAsyncRequest final : public RegisteredAsyncRequest { public: PayloadAsyncRequest(void* registered_method, ServerInterface* server, ServerContext* context, internal::ServerAsyncStreamingInterface* stream, CompletionQueue* call_cq, ServerCompletionQueue* notification_cq, void* tag, Message* request) : RegisteredAsyncRequest(server, context, stream, call_cq, tag), registered_method_(registered_method), server_(server), context_(context), stream_(stream), call_cq_(call_cq), notification_cq_(notification_cq), tag_(tag), request_(request) { IssueRequest(registered_method, payload_.bbuf_ptr(), notification_cq); } ~PayloadAsyncRequest() { payload_.Release(); // We do not own the payload_ } bool FinalizeResult(void** tag, bool* status) override { if (*status) { if (!payload_.Valid() || !SerializationTraits::Deserialize( payload_.bbuf_ptr(), request_) .ok()) { // If deserialization fails, we cancel the call and instantiate // a new instance of ourselves to request another call. We then // return false, which prevents the call from being returned to // the application. g_core_codegen_interface->grpc_call_cancel_with_status( call_, GRPC_STATUS_INTERNAL, "Unable to parse request", nullptr); g_core_codegen_interface->grpc_call_unref(call_); new PayloadAsyncRequest(registered_method_, server_, context_, stream_, call_cq_, notification_cq_, tag_, request_); delete this; return false; } } return RegisteredAsyncRequest::FinalizeResult(tag, status); } private: void* const registered_method_; ServerInterface* const server_; ServerContext* const context_; internal::ServerAsyncStreamingInterface* const stream_; CompletionQueue* const call_cq_; ServerCompletionQueue* const notification_cq_; void* const tag_; Message* const request_; ByteBuffer payload_; }; class GenericAsyncRequest : public BaseAsyncRequest { public: GenericAsyncRequest(ServerInterface* server, GenericServerContext* context, internal::ServerAsyncStreamingInterface* stream, CompletionQueue* call_cq, ServerCompletionQueue* notification_cq, void* tag, bool delete_on_finalize); bool FinalizeResult(void** tag, bool* status) override; private: grpc_call_details call_details_; }; template void RequestAsyncCall(internal::RpcServiceMethod* method, ServerContext* context, internal::ServerAsyncStreamingInterface* stream, CompletionQueue* call_cq, ServerCompletionQueue* notification_cq, void* tag, Message* message) { GPR_CODEGEN_ASSERT(method); new PayloadAsyncRequest(method->server_tag(), this, context, stream, call_cq, notification_cq, tag, message); } void RequestAsyncCall(internal::RpcServiceMethod* method, ServerContext* context, internal::ServerAsyncStreamingInterface* stream, CompletionQueue* call_cq, ServerCompletionQueue* notification_cq, void* tag) { GPR_CODEGEN_ASSERT(method); new NoPayloadAsyncRequest(method->server_tag(), this, context, stream, call_cq, notification_cq, tag); } void RequestAsyncGenericCall(GenericServerContext* context, internal::ServerAsyncStreamingInterface* stream, CompletionQueue* call_cq, ServerCompletionQueue* notification_cq, void* tag) { new GenericAsyncRequest(this, context, stream, call_cq, notification_cq, tag, true); } }; } // namespace grpc #endif // GRPCPP_IMPL_CODEGEN_SERVER_INTERFACE_H