client.h

// 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 KUDU_CLIENT_CLIENT_H
#define KUDU_CLIENT_CLIENT_H
 
#include <stdint.h>
 
#include <cstddef>
#include <map>
// Not safe to include <memory>; this header must remain compatible with C++98.
//
// IWYU pragma: no_include <memory>
#include <string>
#include <vector>
 
#include "kudu/client/row_result.h"
#include "kudu/client/scan_predicate.h"
#include "kudu/client/schema.h"
#include "kudu/client/shared_ptr.h" // IWYU pragma: keep
#ifdef KUDU_HEADERS_NO_STUBS
#include <gtest/gtest_prod.h>
 
#include "kudu/gutil/macros.h"
#include "kudu/gutil/port.h"
#else
#include "kudu/client/stubs.h"
#endif
#include "kudu/util/kudu_export.h"
#include "kudu/util/slice.h"
#include "kudu/util/status.h"
 
namespace kudu {
 
class AlterTableTest;
class AuthzTokenTest;
class ClientStressTest_TestUniqueClientIds_Test;
class DisableWriteWhenExceedingQuotaTest;
class KuduPartialRow;
class MetaCacheLookupStressTest_PerfSynthetic_Test;
class MonoDelta;
class Partition;
class PartitionSchema;
class SecurityUnknownTskTest;
class TxnId;
 
namespace client {
class KuduClient;
class KuduTable;
} // namespace client
 
namespace tablet {
class FuzzTest;
} // namespace tablet
 
namespace transactions {
class CoordinatorRpc;
class ParticipantRpc;
class TxnSystemClient;
} // namespace transactions
 
namespace tools {
class LeaderMasterProxy;
class RemoteKsckCluster;
class TableAlter;
class TableLister;
Status ShowTabletInfo(const std::vector<std::string>& master_addresses,
                      const std::vector<std::string>& tablet_id);
} // namespace tools
 
namespace client {
 
class KuduColumnarScanBatch;
class KuduDelete;
class KuduDeleteIgnore;
class KuduInsert;
class KuduInsertIgnore;
class KuduLoggingCallback;
class KuduPartitioner;
class KuduScanBatch;
class KuduSession;
class KuduStatusCallback;
class KuduTableAlterer;
class KuduTableCreator;
class KuduTableStatistics;
class KuduTablet;
class KuduTabletServer;
class KuduUpdate;
class KuduUpdateIgnore;
class KuduUpsert;
class KuduUpsertIgnore;
class KuduValue;
class KuduWriteOperation;
class ResourceMetrics;
 
namespace internal {
class Batcher;
class ErrorCollector;
class GetTableSchemaRpc;
class LookupRpc;
class MetaCache;
class RemoteTablet;
class RemoteTabletServer;
class ReplicaController;
class RetrieveAuthzTokenRpc;
class ScanBatchDataInterface;
class TabletInfoProvider;
class WriteRpc;
template <class ReqClass, class RespClass>
class AsyncLeaderMasterRpc; // IWYU pragma: keep
template <class ReqClass, class RespClass>
class AsyncRandomTxnManagerRpc; // IWYU pragma: keep
} // namespace internal

void KUDU_EXPORT InstallLoggingCallback(KuduLoggingCallback* cb);

void KUDU_EXPORT UninstallLoggingCallback();

void KUDU_EXPORT SetVerboseLogLevel(int level);

Status KUDU_EXPORT SetInternalSignalNumber(int signum) WARN_UNUSED_RESULT;

Status KUDU_EXPORT DisableSaslInitialization() WARN_UNUSED_RESULT;
 

Status KUDU_EXPORT DisableOpenSSLInitialization() WARN_UNUSED_RESULT;

std::string KUDU_EXPORT GetShortVersionString();

std::string KUDU_EXPORT GetAllVersionInfo();

class KUDU_EXPORT KuduClientBuilder {
 public:
  KuduClientBuilder();
  ~KuduClientBuilder();

  enum EncryptionPolicy {
    OPTIONAL,        
 
    REQUIRED_REMOTE, 
 
    REQUIRED         
  };

  KuduClientBuilder& clear_master_server_addrs();

  KuduClientBuilder& master_server_addrs(const std::vector<std::string>& addrs);

  KuduClientBuilder& add_master_server_addr(const std::string& addr);

  KuduClientBuilder& default_admin_operation_timeout(const MonoDelta& timeout);

  KuduClientBuilder& default_rpc_timeout(const MonoDelta& timeout);

  KuduClientBuilder& connection_negotiation_timeout(const MonoDelta& timeout);

  KuduClientBuilder& rpc_max_message_size(int64_t size);

  KuduClientBuilder& jwt(const std::string& jwt);

  KuduClientBuilder& import_authentication_credentials(std::string authn_creds);

  KuduClientBuilder& trusted_certificate(const std::string& cert_pem);

  KuduClientBuilder& num_reactors(int num_reactors);

  KuduClientBuilder& sasl_protocol_name(const std::string& sasl_protocol_name);

  KuduClientBuilder& require_authentication(bool require_authentication);

  KuduClientBuilder& encryption_policy(EncryptionPolicy encryption_policy);

  Status Build(sp::shared_ptr<KuduClient>* client);
 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class internal::ReplicaController;
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduClientBuilder);
};

class KUDU_EXPORT KuduTransaction :
    public sp::enable_shared_from_this<KuduTransaction> {
 public:
  ~KuduTransaction();

  Status CreateSession(sp::shared_ptr<KuduSession>* session) WARN_UNUSED_RESULT;

  Status Commit() WARN_UNUSED_RESULT;

  Status StartCommit() WARN_UNUSED_RESULT;

  Status IsCommitComplete(bool* is_complete,
                          Status* completion_status) WARN_UNUSED_RESULT;

  Status Rollback() WARN_UNUSED_RESULT;

  class KUDU_EXPORT SerializationOptions {
   public:
    SerializationOptions();
    ~SerializationOptions();

    bool keepalive() const;

    SerializationOptions& enable_keepalive(bool enable);
 
   private:
    friend class KuduTransaction;
    class KUDU_NO_EXPORT Data;
 
    Data* data_; // Owned.
 
    DISALLOW_COPY_AND_ASSIGN(SerializationOptions);
  };

  Status Serialize(
      std::string* serialized_txn,
      const SerializationOptions& options = SerializationOptions()) const WARN_UNUSED_RESULT;

  static Status Deserialize(const sp::shared_ptr<KuduClient>& client,
                            const std::string& serialized_txn,
                            sp::shared_ptr<KuduTransaction>* txn) WARN_UNUSED_RESULT;
 private:
  DISALLOW_COPY_AND_ASSIGN(KuduTransaction);
 
  friend class KuduClient;
  friend class KuduSession;
  FRIEND_TEST(ClientTest, TxnIdOfTransactionalSession);
  FRIEND_TEST(ClientTest, TxnToken);
 
  class KUDU_NO_EXPORT Data;
 
  explicit KuduTransaction(const sp::shared_ptr<KuduClient>& client);
  Data* data_; // Owned.
};

class KUDU_EXPORT KuduClient : public sp::enable_shared_from_this<KuduClient> {
 public:
  ~KuduClient();

  KuduTableCreator* NewTableCreator();

  Status IsCreateTableInProgress(const std::string& table_name,
                                 bool* create_in_progress);

  Status DeleteTable(const std::string& table_name);


  Status SoftDeleteTable(const std::string& table_name,
                         uint32_t reserve_seconds = 0);


  Status DeleteTableInCatalogs(const std::string& table_name,
                               bool modify_external_catalogs,
                               int32_t reserve_seconds = -1) KUDU_NO_EXPORT;

  Status RecallTable(const std::string& table_id, const std::string& new_table_name = "");


  KuduTableAlterer* NewTableAlterer(const std::string& table_name);

  Status IsAlterTableInProgress(const std::string& table_name,
                                bool* alter_in_progress);
  Status GetTableSchema(const std::string& table_name,
                        KuduSchema* schema);

  Status ListTabletServers(std::vector<KuduTabletServer*>* tablet_servers);

  Status ListTables(std::vector<std::string>* tables,
                    const std::string& filter = "");

  Status ListSoftDeletedTables(std::vector<std::string>* tables,
                               const std::string& filter = "");

  Status TableExists(const std::string& table_name, bool* exists);

  Status OpenTable(const std::string& table_name,
                   sp::shared_ptr<KuduTable>* table);

  sp::shared_ptr<KuduSession> NewSession();

  Status NewTransaction(sp::shared_ptr<KuduTransaction>* txn) WARN_UNUSED_RESULT;


  Status GetTablet(const std::string& tablet_id,
                   KuduTablet** tablet) KUDU_NO_EXPORT;

  Status GetTableStatistics(const std::string& table_name,
                            KuduTableStatistics** statistics);

  std::string GetMasterAddresses() const KUDU_NO_EXPORT;


  enum ReplicaSelection {
    LEADER_ONLY,      
 
    CLOSEST_REPLICA,  
 
    FIRST_REPLICA     
  };

  bool IsMultiMaster() const;

  const MonoDelta& default_admin_operation_timeout() const;

  const MonoDelta& default_rpc_timeout() const;

  MonoDelta connection_negotiation_timeout() const;

  static const uint64_t kNoTimestamp;

  uint64_t GetLatestObservedTimestamp() const;

  void SetLatestObservedTimestamp(uint64_t ht_timestamp);

  Status ExportAuthenticationCredentials(std::string* authn_creds) const;


  std::string GetHiveMetastoreUris() const KUDU_NO_EXPORT;

  bool GetHiveMetastoreSaslEnabled() const KUDU_NO_EXPORT;

  std::string GetHiveMetastoreUuid() const KUDU_NO_EXPORT;

  std::string location() const KUDU_NO_EXPORT;

  std::string cluster_id() const KUDU_NO_EXPORT;
 
 private:
  class KUDU_NO_EXPORT Data;
 
  template <class ReqClass, class RespClass>
  friend class internal::AsyncLeaderMasterRpc;
  template <class ReqClass, class RespClass>
  friend class internal::AsyncRandomTxnManagerRpc;
 
  friend class ClientTest;
  friend class ConnectToClusterBaseTest;
  friend class KuduClientBuilder;
  friend class KuduPartitionerBuilder;
  friend class KuduTransaction;
  friend class KuduScanToken;
  friend class KuduScanTokenBuilder;
  friend class KuduScanner;
  friend class KuduSession;
  friend class KuduTable;
  friend class KuduTableAlterer;
  friend class KuduTableCreator;
  friend class internal::Batcher;
  friend class internal::GetTableSchemaRpc;
  friend class internal::LookupRpc;
  friend class internal::MetaCache;
  friend class internal::RemoteTablet;
  friend class internal::RemoteTabletServer;
  friend class internal::RetrieveAuthzTokenRpc;
  friend class internal::TabletInfoProvider;
  friend class internal::WriteRpc;
  friend class kudu::AuthzTokenTest;
  friend class kudu::DisableWriteWhenExceedingQuotaTest;
  friend class kudu::SecurityUnknownTskTest;
  friend class transactions::CoordinatorRpc;
  friend class transactions::ParticipantRpc;
  friend class transactions::TxnSystemClient;
  friend class tools::LeaderMasterProxy;
  friend class tools::RemoteKsckCluster;
  friend class tools::TableLister;
  friend class KeepAlivePeriodicallyTest;
  friend class ScanTokenTest;
  friend Status tools::ShowTabletInfo(const std::vector<std::string>& master_addresses,
                                      const std::vector<std::string>& tablet_id);
 
  FRIEND_TEST(kudu::ClientStressTest, TestUniqueClientIds);
  FRIEND_TEST(kudu::MetaCacheLookupStressTest, PerfSynthetic);
  FRIEND_TEST(ClientTest, ClearCacheAndConcurrentWorkload);
  FRIEND_TEST(ClientTest, ConnectionNegotiationTimeout);
  FRIEND_TEST(ClientTest, TestBasicIdBasedLookup);
  FRIEND_TEST(ClientTest, TestCacheAuthzTokens);
  FRIEND_TEST(ClientTest, TestGetSecurityInfoFromMaster);
  FRIEND_TEST(ClientTest, TestGetTabletServerBlacklist);
  FRIEND_TEST(ClientTest, TestGetTabletServerDeterministic);
  FRIEND_TEST(ClientTest, TestMasterDown);
  FRIEND_TEST(ClientTest, TestMasterLookupPermits);
  FRIEND_TEST(ClientTest, TestMetaCacheExpiry);
  FRIEND_TEST(ClientTest, TestMetaCacheExpiryById);
  FRIEND_TEST(ClientTest, TestMetaCacheExpiryWithKeysAndIds);
  FRIEND_TEST(ClientTest, TestMetaCacheLookupNoLeaders);
  FRIEND_TEST(ClientTest, TestMetaCacheWithKeysAndIds);
  FRIEND_TEST(ClientTest, TestNonCoveringRangePartitions);
  FRIEND_TEST(ClientTest, TestRetrieveAuthzTokenInParallel);
  FRIEND_TEST(ClientTest, TestReplicatedTabletWritesWithLeaderElection);
  FRIEND_TEST(ClientTest, TestScanFaultTolerance);
  FRIEND_TEST(ClientTest, TestScanTimeout);
  FRIEND_TEST(ClientTest, TestWriteWithDeadMaster);
  FRIEND_TEST(MasterFailoverTest, TestPauseAfterCreateTableIssued);
  FRIEND_TEST(MultiTServerClientTest, TestSetReplicationFactor);
 
  KuduClient();
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduClient);
};

class KUDU_EXPORT KuduTabletServer {
 public:
  ~KuduTabletServer();

  const std::string& uuid() const;

  const std::string& hostname() const;

  uint16_t port() const;


  const std::string& location() const KUDU_NO_EXPORT;
 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class KuduClient;
  friend class KuduScanner;
  friend class KuduScanTokenBuilder;
  friend Status tools::ShowTabletInfo(const std::vector<std::string>& master_addresses,
                                      const std::vector<std::string>& tablet_id);
 
  KuduTabletServer();
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduTabletServer);
};

class KUDU_EXPORT KuduReplica {
 public:
  ~KuduReplica();

  bool is_leader() const;

  const KuduTabletServer& ts() const;
 
 private:
  friend class KuduClient;
  friend class KuduScanTokenBuilder;
  friend class internal::ReplicaController;
 
  class KUDU_NO_EXPORT Data;
 
  KuduReplica();
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduReplica);
};

class KUDU_EXPORT KuduTablet {
 public:
  ~KuduTablet();

  const std::string& id() const;

  const std::vector<const KuduReplica*>& replicas() const;
 
 private:
  friend class KuduClient;
  friend class KuduScanTokenBuilder;
 
  class KUDU_NO_EXPORT Data;
 
  KuduTablet();
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduTablet);
};

class KUDU_EXPORT KuduTableCreator {
 public:
  ~KuduTableCreator();

  KuduTableCreator& table_name(const std::string& name);

  KuduTableCreator& schema(const KuduSchema* schema);

  KuduTableCreator& add_hash_partitions(const std::vector<std::string>& columns,
                                        int32_t num_buckets);

  KuduTableCreator& add_hash_partitions(const std::vector<std::string>& columns,
                                        int32_t num_buckets,
                                        int32_t seed);

  KuduTableCreator& set_range_partition_columns(const std::vector<std::string>& columns);

  enum RangePartitionBound {
    EXCLUSIVE_BOUND, 
    INCLUSIVE_BOUND, 
  };

  KuduTableCreator& add_range_partition(KuduPartialRow* lower_bound,
                                        KuduPartialRow* upper_bound,
                                        RangePartitionBound lower_bound_type = INCLUSIVE_BOUND,
                                        RangePartitionBound upper_bound_type = EXCLUSIVE_BOUND);

  KuduTableCreator& add_custom_range_partition(
      class KuduRangePartition* partition);

  KuduTableCreator& add_range_partition_split(KuduPartialRow* split_row);

  KuduTableCreator& set_owner(const std::string& owner);

  KuduTableCreator& set_comment(const std::string& comment);
 

  KuduTableCreator& set_allow_empty_partition(bool allow_empty_partition);

  KuduTableCreator& split_rows(const std::vector<const KuduPartialRow*>& split_rows)
      ATTRIBUTE_DEPRECATED("use add_range_partition_split() instead");

  KuduTableCreator& num_replicas(int n_replicas);

  KuduTableCreator& dimension_label(const std::string& dimension_label);

  KuduTableCreator& extra_configs(const std::map<std::string, std::string>& extra_configs);

  KuduTableCreator& timeout(const MonoDelta& timeout);

  KuduTableCreator& wait(bool wait);

  Status Create();
 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class KuduClient;
  friend class transactions::TxnSystemClient;
 
  explicit KuduTableCreator(KuduClient* client);
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduTableCreator);
};

class KUDU_EXPORT KuduRangePartition {
 public:
  KuduRangePartition(KuduPartialRow* lower_bound,
                     KuduPartialRow* upper_bound,
                     KuduTableCreator::RangePartitionBound lower_bound_type =
      KuduTableCreator::INCLUSIVE_BOUND,
                     KuduTableCreator::RangePartitionBound upper_bound_type =
      KuduTableCreator::EXCLUSIVE_BOUND);
 
  ~KuduRangePartition();

  Status add_hash_partitions(const std::vector<std::string>& columns,
                             int32_t num_buckets,
                             int32_t seed = 0);
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class KuduTableCreator;
  friend class KuduTableAlterer;
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduRangePartition);
};

class KUDU_EXPORT KuduTableStatistics {
 public:
  KuduTableStatistics();
  ~KuduTableStatistics();

  int64_t on_disk_size() const;

  int64_t live_row_count() const;

  int64_t on_disk_size_limit() const;

  int64_t live_row_count_limit() const;

  std::string ToString() const;
 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class KuduClient;
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduTableStatistics);
};

class KUDU_EXPORT KuduTable : public sp::enable_shared_from_this<KuduTable> {
 public:
  ~KuduTable();

  const std::string& name() const;

  const std::string& id() const;

  const KuduSchema& schema() const;

  const std::string& comment() const;

  int num_replicas() const;

  const std::string& owner() const;

  KuduInsert* NewInsert();

  KuduInsertIgnore* NewInsertIgnore();

  KuduUpsert* NewUpsert();

  KuduUpsertIgnore* NewUpsertIgnore();

  KuduUpdate* NewUpdate();

  KuduUpdateIgnore* NewUpdateIgnore();

  KuduDelete* NewDelete();

  KuduDeleteIgnore* NewDeleteIgnore();

  KuduPredicate* NewComparisonPredicate(const Slice& col_name,
                                        KuduPredicate::ComparisonOp op,
                                        KuduValue* value);

  KuduPredicate* NewInBloomFilterPredicate(const Slice& col_name,
                                           std::vector<KuduBloomFilter*>* bloom_filters);


  KuduPredicate* NewInBloomFilterPredicate(const Slice& col_name,
                                           const std::vector<Slice>& bloom_filters);

  KuduPredicate* NewInListPredicate(const Slice& col_name,
                                    std::vector<KuduValue*>* values);

  KuduPredicate* NewIsNotNullPredicate(const Slice& col_name);

  KuduPredicate* NewIsNullPredicate(const Slice& col_name);

  KuduClient* client() const;

  const PartitionSchema& partition_schema() const;

  const std::map<std::string, std::string>& extra_configs() const;


  Status ListPartitions(std::vector<Partition>* partitions) KUDU_NO_EXPORT;

 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class KuduClient;
  friend class KuduPartitioner;
  friend class KuduScanToken;
  friend class KuduScanner;
 
  KuduTable(const sp::shared_ptr<KuduClient>& client,
            const std::string& name,
            const std::string& id,
            int num_replicas,
            const std::string& owner,
            const std::string& comment,
            const KuduSchema& schema,
            const PartitionSchema& partition_schema,
            const std::map<std::string, std::string>& extra_configs);
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduTable);
};

class KUDU_EXPORT KuduTableAlterer {
 public:
  ~KuduTableAlterer();

  KuduTableAlterer* RenameTo(const std::string& new_name);

  KuduTableAlterer* SetOwner(const std::string& new_owner);

  KuduTableAlterer* SetComment(const std::string& new_comment);

  KuduColumnSpec* AddColumn(const std::string& name);

  KuduColumnSpec* AlterColumn(const std::string& name);

  KuduTableAlterer* DropColumn(const std::string& name);

  KuduTableAlterer* AddRangePartition(
      KuduPartialRow* lower_bound,
      KuduPartialRow* upper_bound,
      KuduTableCreator::RangePartitionBound lower_bound_type = KuduTableCreator::INCLUSIVE_BOUND,
      KuduTableCreator::RangePartitionBound upper_bound_type = KuduTableCreator::EXCLUSIVE_BOUND);

  KuduTableAlterer* AddRangePartition(KuduRangePartition* partition);

  KuduTableAlterer* AddRangePartitionWithDimension(
      KuduPartialRow* lower_bound,
      KuduPartialRow* upper_bound,
      const std::string& dimension_label,
      KuduTableCreator::RangePartitionBound lower_bound_type = KuduTableCreator::INCLUSIVE_BOUND,
      KuduTableCreator::RangePartitionBound upper_bound_type = KuduTableCreator::EXCLUSIVE_BOUND);

  KuduTableAlterer* DropRangePartition(
      KuduPartialRow* lower_bound,
      KuduPartialRow* upper_bound,
      KuduTableCreator::RangePartitionBound lower_bound_type = KuduTableCreator::INCLUSIVE_BOUND,
      KuduTableCreator::RangePartitionBound upper_bound_type = KuduTableCreator::EXCLUSIVE_BOUND);

  KuduTableAlterer* AlterExtraConfig(const std::map<std::string, std::string>& extra_configs);

  KuduTableAlterer* SetTableDiskSizeLimit(int64_t disk_size_limit);

  KuduTableAlterer* SetTableRowCountLimit(int64_t row_count_limit);

  KuduTableAlterer* timeout(const MonoDelta& timeout);

  KuduTableAlterer* wait(bool wait);


  KuduTableAlterer* modify_external_catalogs(bool modify_external_catalogs) KUDU_NO_EXPORT;


  Status Alter();
 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class KuduClient;
  friend class tools::TableAlter;
  friend class kudu::AlterTableTest;
 
  FRIEND_TEST(MultiTServerClientTest, TestSetReplicationFactor);
 
  KuduTableAlterer(KuduClient* client,
                   const std::string& name);
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduTableAlterer);
};

class KUDU_EXPORT KuduError {
 public:
  ~KuduError();

  const Status& status() const;

  const KuduWriteOperation& failed_op() const;

  KuduWriteOperation* release_failed_op();

  bool was_possibly_successful() const;
 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class internal::Batcher;
  friend class internal::ErrorCollector;
  friend class KuduSession;
 
  KuduError(KuduWriteOperation* failed_op, const Status& error);
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduError);
};
 

class KUDU_EXPORT KuduSession : public sp::enable_shared_from_this<KuduSession> {
 public:
  ~KuduSession();

  enum FlushMode {
    AUTO_FLUSH_SYNC,

    AUTO_FLUSH_BACKGROUND,

    MANUAL_FLUSH
  };

  Status SetFlushMode(FlushMode m) WARN_UNUSED_RESULT;

  enum ExternalConsistencyMode {
    CLIENT_PROPAGATED,

    COMMIT_WAIT
  };

  Status SetExternalConsistencyMode(ExternalConsistencyMode m)
    WARN_UNUSED_RESULT;

  Status SetMutationBufferSpace(size_t size_bytes) WARN_UNUSED_RESULT;

  Status SetMutationBufferFlushWatermark(double watermark_pct)
      WARN_UNUSED_RESULT;

  Status SetMutationBufferFlushInterval(unsigned int millis) WARN_UNUSED_RESULT;

  Status SetMutationBufferMaxNum(unsigned int max_num) WARN_UNUSED_RESULT;

  void SetTimeoutMillis(int millis);


  Status Apply(KuduWriteOperation* write_op) WARN_UNUSED_RESULT;

  Status Flush() WARN_UNUSED_RESULT;

  void FlushAsync(KuduStatusCallback* cb);

  Status Close() WARN_UNUSED_RESULT;

  bool HasPendingOperations() const;

  int CountBufferedOperations() const
      ATTRIBUTE_DEPRECATED("this method is experimental and will disappear "
                           "in a future release");

  Status SetErrorBufferSpace(size_t size_bytes);

  int CountPendingErrors() const;

  void GetPendingErrors(std::vector<KuduError*>* errors, bool* overflowed);

  KuduClient* client() const;

  const ResourceMetrics& GetWriteOpMetrics() const;
 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class ClientTest;
  friend class KuduClient;
  friend class KuduTransaction;
  friend class internal::Batcher;
  friend class tablet::FuzzTest;
  FRIEND_TEST(ClientTest, TestAutoFlushBackgroundAndErrorCollector);
  FRIEND_TEST(ClientTest, TestAutoFlushBackgroundApplyBlocks);
  FRIEND_TEST(ClientTest, TxnIdOfTransactionalSession);
 
  explicit KuduSession(const sp::shared_ptr<KuduClient>& client);
  KuduSession(const sp::shared_ptr<KuduClient>& client, const TxnId& txn_id);
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduSession);
};
 

class KUDU_EXPORT KuduScanner {
 public:
  enum ReadMode {
    READ_LATEST,

    READ_AT_SNAPSHOT,

    READ_YOUR_WRITES
  };

  enum OrderMode {
    UNORDERED,

    ORDERED
  };

  enum { kScanTimeoutMillis = 30000 };

  explicit KuduScanner(KuduTable* table);
 
  ~KuduScanner();

  Status SetProjectedColumnNames(const std::vector<std::string>& col_names)
    WARN_UNUSED_RESULT;

  Status SetProjectedColumnIndexes(const std::vector<int>& col_indexes)
    WARN_UNUSED_RESULT;

  Status SetProjectedColumns(const std::vector<std::string>& col_names)
      WARN_UNUSED_RESULT
      ATTRIBUTE_DEPRECATED("use SetProjectedColumnNames() instead");

  Status SetQueryId(const std::string& query_id);

  Status AddConjunctPredicate(KuduPredicate* pred) WARN_UNUSED_RESULT;

  Status AddLowerBound(const KuduPartialRow& key);

  Status AddLowerBoundRaw(const Slice& key)
      ATTRIBUTE_DEPRECATED("use AddLowerBound() instead");

  Status AddExclusiveUpperBound(const KuduPartialRow& key);

  Status AddExclusiveUpperBoundRaw(const Slice& key)
      ATTRIBUTE_DEPRECATED("use AddExclusiveUpperBound() instead");

  Status AddLowerBoundPartitionKeyRaw(const Slice& partition_key);

  Status AddExclusiveUpperBoundPartitionKeyRaw(const Slice& partition_key);

  Status SetCacheBlocks(bool cache_blocks);

  Status Open();

  Status KeepAlive();

  Status StartKeepAlivePeriodically(uint64_t keep_alive_interval_ms = 30000);

  void StopKeepAlivePeriodically();

  void Close();

  bool HasMoreRows() const;

  Status NextBatch(std::vector<KuduRowResult>* rows)
      ATTRIBUTE_DEPRECATED("use NextBatch(KuduScanBatch*) instead");

  Status NextBatch(KuduScanBatch* batch);

  Status NextBatch(KuduColumnarScanBatch* batch);

  Status GetCurrentServer(KuduTabletServer** server);

  const ResourceMetrics& GetResourceMetrics() const;

  Status SetBatchSizeBytes(uint32_t batch_size);

  Status SetSelection(KuduClient::ReplicaSelection selection)
    WARN_UNUSED_RESULT;

  Status SetReadMode(ReadMode read_mode) WARN_UNUSED_RESULT;

  Status SetOrderMode(OrderMode order_mode) WARN_UNUSED_RESULT
      ATTRIBUTE_DEPRECATED("use SetFaultTolerant() instead");

  Status SetFaultTolerant() WARN_UNUSED_RESULT;

  Status SetSnapshotMicros(uint64_t snapshot_timestamp_micros) WARN_UNUSED_RESULT;

  Status SetSnapshotRaw(uint64_t snapshot_timestamp) WARN_UNUSED_RESULT;


  Status SetDiffScan(uint64_t start_timestamp, uint64_t end_timestamp)
      WARN_UNUSED_RESULT KUDU_NO_EXPORT;


  Status SetTimeoutMillis(int millis);

  KuduSchema GetProjectionSchema() const;

  sp::shared_ptr<KuduTable> GetKuduTable();


  static const uint64_t NO_FLAGS = 0;
  static const uint64_t PAD_UNIXTIME_MICROS_TO_16_BYTES = 1 << 0;

  static const uint64_t COLUMNAR_LAYOUT = 1 << 1;

  Status SetRowFormatFlags(uint64_t flags);

  Status SetLimit(int64_t limit) WARN_UNUSED_RESULT;

  std::string ToString() const;
 
 private:
  class KUDU_NO_EXPORT Data;
 
  Status NextBatch(internal::ScanBatchDataInterface* batch);
 
  friend class KuduScanToken;
  friend class FlexPartitioningTest;
  FRIEND_TEST(ClientTest, TestBlockScannerHijackingAttempts);
  FRIEND_TEST(ClientTest, TestScanCloseProxy);
  FRIEND_TEST(ClientTest, TestScanFaultTolerance);
  FRIEND_TEST(ClientTest, TestScanNoBlockCaching);
  FRIEND_TEST(ClientTest, TestScanTimeout);
  FRIEND_TEST(ClientTest, TestScanWithQueryId);
  FRIEND_TEST(ClientTest, TestReadAtSnapshotNoTimestampSet);
  FRIEND_TEST(ConsistencyITest, TestSnapshotScanTimestampReuse);
  FRIEND_TEST(KeepAlivePeriodicallyTest, TestScannerKeepAlivePeriodicallyCrossServers);
  FRIEND_TEST(KeepAlivePeriodicallyTest, TestScannerKeepAlivePeriodicallyScannerTolerate);
  FRIEND_TEST(KeepAlivePeriodicallyTest, TestStopKeepAlivePeriodically);
  FRIEND_TEST(ScanTokenTest, TestScanTokens);
  FRIEND_TEST(ScanTokenTest, TestScanTokens_NonUniquePrimaryKey);
  FRIEND_TEST(ScanTokenTest, TestScanTokensWithQueryId);
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduScanner);
};

class KUDU_EXPORT KuduScanToken {
 public:
 
  ~KuduScanToken();

  Status IntoKuduScanner(KuduScanner** scanner) const WARN_UNUSED_RESULT;

  const KuduTablet& tablet() const;

  Status Serialize(std::string* buf) const WARN_UNUSED_RESULT;

  static Status DeserializeIntoScanner(KuduClient* client,
                                       const std::string& serialized_token,
                                       KuduScanner** scanner) WARN_UNUSED_RESULT;
 
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class KuduScanTokenBuilder;
 
  KuduScanToken();
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduScanToken);
};

class KUDU_EXPORT KuduScanTokenBuilder {
 public:

  explicit KuduScanTokenBuilder(KuduTable* table);
  ~KuduScanTokenBuilder();

  Status SetProjectedColumnNames(const std::vector<std::string>& col_names)
    WARN_UNUSED_RESULT;

  Status SetProjectedColumnIndexes(const std::vector<int>& col_indexes)
    WARN_UNUSED_RESULT;

  Status AddConjunctPredicate(KuduPredicate* pred) WARN_UNUSED_RESULT;

  Status AddLowerBound(const KuduPartialRow& key) WARN_UNUSED_RESULT;

  Status AddUpperBound(const KuduPartialRow& key) WARN_UNUSED_RESULT;

  Status SetCacheBlocks(bool cache_blocks) WARN_UNUSED_RESULT;

  Status SetBatchSizeBytes(uint32_t batch_size) WARN_UNUSED_RESULT;

  Status SetSelection(KuduClient::ReplicaSelection selection)
    WARN_UNUSED_RESULT;

  Status SetReadMode(KuduScanner::ReadMode read_mode) WARN_UNUSED_RESULT;

  Status SetFaultTolerant() WARN_UNUSED_RESULT;

  Status SetSnapshotMicros(uint64_t snapshot_timestamp_micros)
    WARN_UNUSED_RESULT;

  Status SetSnapshotRaw(uint64_t snapshot_timestamp) WARN_UNUSED_RESULT;


  Status SetDiffScan(uint64_t start_timestamp, uint64_t end_timestamp)
      WARN_UNUSED_RESULT KUDU_NO_EXPORT;

  Status SetTimeoutMillis(int millis) WARN_UNUSED_RESULT;

  Status IncludeTableMetadata(bool include_metadata) WARN_UNUSED_RESULT;

  Status IncludeTabletMetadata(bool include_metadata) WARN_UNUSED_RESULT;

  Status SetQueryId(const std::string& query_id);

  void SetSplitSizeBytes(uint64_t split_size_bytes);

  Status Build(std::vector<KuduScanToken*>* tokens) WARN_UNUSED_RESULT;
 
 private:
  class KUDU_NO_EXPORT Data;
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduScanTokenBuilder);
};

class KUDU_EXPORT KuduPartitionerBuilder {
 public:
  explicit KuduPartitionerBuilder(sp::shared_ptr<KuduTable> table);
  ~KuduPartitionerBuilder();

  KuduPartitionerBuilder* SetBuildTimeout(MonoDelta timeout);

  Status Build(KuduPartitioner** partitioner);
 private:
  class KUDU_NO_EXPORT Data;
 
  // Owned.
  Data* data_;
 
  DISALLOW_COPY_AND_ASSIGN(KuduPartitionerBuilder);
};

class KUDU_EXPORT KuduPartitioner {
 public:
  ~KuduPartitioner();

  int NumPartitions() const;

  Status PartitionRow(const KuduPartialRow& row, int* partition);
 private:
  class KUDU_NO_EXPORT Data;
 
  friend class KuduPartitionerBuilder;
 
  explicit KuduPartitioner(Data* data);
  Data* data_; // Owned.
 
  DISALLOW_COPY_AND_ASSIGN(KuduPartitioner);
};
 
 
} // namespace client
} // namespace kudu
#endif