grpc/include/grpc++/impl/rpc_service_method.h

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#ifndef GRPCXX_IMPL_RPC_SERVICE_METHOD_H
#define GRPCXX_IMPL_RPC_SERVICE_METHOD_H

#include <climits>
#include <functional>
#include <map>
#include <memory>
#include <vector>

#include <grpc++/impl/rpc_method.h>
#include <grpc++/support/config.h>
#include <grpc++/support/status.h>

namespace grpc {
class ServerContext;
class StreamContextInterface;

// Base class for running an RPC handler.
class MethodHandler {
 public:
  virtual ~MethodHandler() {}
  struct HandlerParameter {
    HandlerParameter(Call* c, ServerContext* context, grpc_byte_buffer* req,
                     int max_size)
        : call(c),
          server_context(context),
          request(req),
          max_message_size(max_size) {}
    Call* call;
    ServerContext* server_context;
    // Handler required to grpc_byte_buffer_destroy this
    grpc_byte_buffer* request;
    int max_message_size;
  };
  virtual void RunHandler(const HandlerParameter& param) = 0;
};

// Server side rpc method class
class RpcServiceMethod : public RpcMethod {
 public:
  // Takes ownership of the handler
  RpcServiceMethod(const char* name, RpcMethod::RpcType type,
                   MethodHandler* handler)
      : RpcMethod(name, type), server_tag_(nullptr), handler_(handler) {}

  void set_server_tag(void* tag) { server_tag_ = tag; }
  void* server_tag() const { return server_tag_; }
  // if MethodHandler is nullptr, then this is an async method
  MethodHandler* handler() const { return handler_.get(); }
  void ResetHandler() { handler_.reset(); }

 private:
  void* server_tag_;
  std::unique_ptr<MethodHandler> handler_;
};

}  // namespace grpc

#endif  // GRPCXX_IMPL_RPC_SERVICE_METHOD_H