| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you 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 IMPALA_SERVICE_DATA_STREAM_SERVICE_H |
| #define IMPALA_SERVICE_DATA_STREAM_SERVICE_H |
| |
| #include "gen-cpp/data_stream_service.service.h" |
| |
| #include "common/status.h" |
| |
| namespace kudu { |
| namespace rpc { |
| class RpcContext; |
| } // namespace rpc |
| } // namespace kudu |
| |
| namespace impala { |
| |
| class DataStreamServiceProxy; |
| class MemTracker; |
| class MetricGroup; |
| |
| /// This is singleton class which provides data transmission services between fragment |
| /// instances. The client for this service is implemented in KrpcDataStreamSender. |
| /// The processing of incoming requests is implemented in KrpcDataStreamRecvr. |
| /// KrpcDataStreamMgr is responsible for routing the incoming requests to the |
| /// appropriate receivers. Metrics exposed by the service will be added to 'metric_group'. |
| class DataStreamService : public DataStreamServiceIf { |
| public: |
| DataStreamService(MetricGroup* metric_group); |
| |
| /// Initializes the service by registering it with the singleton RPC manager. |
| /// This mustn't be called until RPC manager has been initialized. |
| Status Init(); |
| |
| /// Returns true iff the 'remote_user' in 'context' is authorized to access |
| /// DataStreamService. On denied access, the RPC is replied to with an error message. |
| /// Authorization is enforced only when Kerberos is enabled. |
| virtual bool Authorize(const google::protobuf::Message* req, |
| google::protobuf::Message* resp, kudu::rpc::RpcContext* context); |
| |
| /// Notifies the receiver to close the data stream specified in 'request'. |
| /// The receiver replies to the client with a status serialized in 'response'. |
| virtual void EndDataStream(const EndDataStreamRequestPB* request, |
| EndDataStreamResponsePB* response, kudu::rpc::RpcContext* context); |
| |
| /// Sends a row batch to the receiver specified in 'request'. |
| /// The receiver replies to the client with a status serialized in 'response'. |
| virtual void TransmitData(const TransmitDataRequestPB* request, |
| TransmitDataResponsePB* response, kudu::rpc::RpcContext* context); |
| |
| /// Respond to a RPC passed in 'response'/'ctx' with 'status' and release |
| /// the payload memory from 'mem_tracker'. Takes ownership of 'ctx'. |
| template<typename ResponsePBType> |
| static void RespondAndReleaseRpc(const Status& status, ResponsePBType* response, |
| kudu::rpc::RpcContext* ctx, MemTracker* mem_tracker); |
| |
| /// Respond to a RPC passed in 'response'/'ctx' with 'status'. Takes ownership of 'ctx'. |
| template<typename ResponsePBType> |
| static void RespondRpc(const Status& status, ResponsePBType* response, |
| kudu::rpc::RpcContext* ctx); |
| |
| MemTracker* mem_tracker() { return mem_tracker_.get(); } |
| |
| /// Gets a DataStreamService proxy to a server with 'address' and 'hostname'. |
| /// The newly created proxy is returned in 'proxy'. Returns error status on failure. |
| static Status GetProxy(const TNetworkAddress& address, const std::string& hostname, |
| std::unique_ptr<DataStreamServiceProxy>* proxy); |
| |
| private: |
| /// Tracks the memory usage of the payloads in the service queue. |
| std::unique_ptr<MemTracker> mem_tracker_; |
| }; |
| |
| } // namespace impala |
| #endif // IMPALA_SERVICE_DATA_STREAM_SERVICE_H |