grpc/include/grpc++/support/channel_arguments.h

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#ifndef GRPCXX_SUPPORT_CHANNEL_ARGUMENTS_H
#define GRPCXX_SUPPORT_CHANNEL_ARGUMENTS_H

#include <vector>
#include <list>

#include <grpc/compression.h>
#include <grpc/grpc.h>
#include <grpc++/support/config.h>

namespace grpc {
namespace testing {
class ChannelArgumentsTest;
}  // namespace testing

/// Options for channel creation. The user can use generic setters to pass
/// key value pairs down to c channel creation code. For grpc related options,
/// concrete setters are provided.
class ChannelArguments {
 public:
  ChannelArguments() {}
  ~ChannelArguments() {}

  ChannelArguments(const ChannelArguments& other);
  ChannelArguments& operator=(ChannelArguments other) {
    Swap(other);
    return *this;
  }

  void Swap(ChannelArguments& other);

  /// Populates this instance with the arguments from \a channel_args. Does not
  /// take ownership of \a channel_args.
  ///
  /// Note that the underlying arguments are shared. Changes made to either \a
  /// channel_args or this instance would be reflected on both.
  void SetChannelArgs(grpc_channel_args* channel_args) const;

  // gRPC specific channel argument setters
  /// Set target name override for SSL host name checking. This option is for
  /// testing only and should never be used in production.
  void SetSslTargetNameOverride(const grpc::string& name);
  // TODO(yangg) add flow control options
  /// Set the compression algorithm for the channel.
  void SetCompressionAlgorithm(grpc_compression_algorithm algorithm);

  // Generic channel argument setters. Only for advanced use cases.
  /// Set an integer argument \a value under \a key.
  void SetInt(const grpc::string& key, int value);

  // Generic channel argument setter. Only for advanced use cases.
  /// Set a pointer argument \a value under \a key. Owership is not transferred.
  void SetPointer(const grpc::string& key, void* value);

  /// Set a textual argument \a value under \a key.
  void SetString(const grpc::string& key, const grpc::string& value);

 private:
  friend class SecureChannelCredentials;
  friend class testing::ChannelArgumentsTest;

  // Returns empty string when it is not set.
  grpc::string GetSslTargetNameOverride() const;

  std::vector<grpc_arg> args_;
  std::list<grpc::string> strings_;
};

}  // namespace grpc

#endif  // GRPCXX_SUPPORT_CHANNEL_ARGUMENTS_H