grpc/include/grpc++/server_context.h

/*
 *
 * Copyright 2014, Google Inc.
 * All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
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 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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#ifndef __GRPCPP_SERVER_CONTEXT_H_
#define __GRPCPP_SERVER_CONTEXT_H_

#include <grpc++/completion_queue.h>

#include <chrono>
#include <map>
#include <mutex>

#include "config.h"

struct gpr_timespec;
struct grpc_metadata;
struct grpc_call;

namespace grpc {

template <class W, class R>
class ServerAsyncReader;
template <class W>
class ServerAsyncWriter;
template <class W>
class ServerAsyncResponseWriter;
template <class R, class W>
class ServerAsyncReaderWriter;
template <class R>
class ServerReader;
template <class W>
class ServerWriter;
template <class R, class W>
class ServerReaderWriter;

class CallOpBuffer;
class Server;

// Interface of server side rpc context.
class ServerContext final {
 public:
  ServerContext();  // for async calls
  ~ServerContext();

  std::chrono::system_clock::time_point absolute_deadline() {
    return deadline_;
  }

  void AddInitialMetadata(const grpc::string& key, const grpc::string& value);
  void AddTrailingMetadata(const grpc::string& key, const grpc::string& value);

  bool IsCancelled() { return completion_op_.CheckCancelled(cq_); }

  std::multimap<grpc::string, grpc::string> client_metadata() {
    return client_metadata_;
  }

 private:
  friend class ::grpc::Server;
  template <class W, class R>
  friend class ::grpc::ServerAsyncReader;
  template <class W>
  friend class ::grpc::ServerAsyncWriter;
  template <class W>
  friend class ::grpc::ServerAsyncResponseWriter;
  template <class R, class W>
  friend class ::grpc::ServerAsyncReaderWriter;
  template <class R>
  friend class ::grpc::ServerReader;
  template <class W>
  friend class ::grpc::ServerWriter;
  template <class R, class W>
  friend class ::grpc::ServerReaderWriter;

  class CompletionOp final : public CompletionQueueTag {
   public:
    bool FinalizeResult(void** tag, bool* status) override;

    bool CheckCancelled(CompletionQueue* cq);

   private:
    std::mutex mu_;
    bool finalized_ = false;
    int cancelled_ = 0;
  };

  ServerContext(gpr_timespec deadline, grpc_metadata* metadata,
                size_t metadata_count);

  CompletionOp completion_op_;

  std::chrono::system_clock::time_point deadline_;
  grpc_call* call_ = nullptr;
  CompletionQueue* cq_ = nullptr;
  bool sent_initial_metadata_ = false;
  std::multimap<grpc::string, grpc::string> client_metadata_;
  std::multimap<grpc::string, grpc::string> initial_metadata_;
  std::multimap<grpc::string, grpc::string> trailing_metadata_;
};

}  // namespace grpc

#endif  // __GRPCPP_SERVER_CONTEXT_H_