common/thrift/CatalogService.thrift - impala - Git at Google

 // 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.

 namespace cpp impala
 namespace java org.apache.impala.thrift

 include "CatalogObjects.thrift"
 include "JniCatalog.thrift"
 include "Types.thrift"
 include "Status.thrift"
 include "Results.thrift"
 include "hive_metastore.thrift"

 // CatalogServer service API and related structs.

 enum CatalogServiceVersion {
   V1
 }

 // Common header included in all CatalogService requests.
 // TODO: The CatalogServiceVersion/protocol version should be part of the header.
 // This would require changes in BDR and break their compatibility story. We should
 // coordinate a joint change somewhere down the line.
 struct TCatalogServiceRequestHeader {
   // The effective user who submitted this request.
   1: optional string requesting_user
 }

 // Returns details on the result of an operation that updates the catalog. Information
 // returned includes the Status of the operations, the catalog version that will contain
 // the update, and the catalog service ID. If SYNC_DDL was set in the query options, it
 // also returns the version of the catalog update that this operation must wait for
 // before returning the response to the client.
 struct TCatalogUpdateResult {
   // The CatalogService service ID this result came from.
   1: required Types.TUniqueId catalog_service_id

   // The Catalog version that will contain this update.
   2: required i64 version

   // The status of the operation, OK if the operation was successful.
   3: required Status.TStatus status

   // True if this is a result of an INVALIDATE METADATA operation.
   4: required bool is_invalidate

   // The resulting TCatalogObjects that were added or modified, if applicable.
   5: optional list<CatalogObjects.TCatalogObject> updated_catalog_objects

   // The resulting TCatalogObjects that were removed, if applicable.
   6: optional list<CatalogObjects.TCatalogObject> removed_catalog_objects
 }

 // Request for executing a DDL operation (CREATE, ALTER, DROP).
 struct TDdlExecRequest {
   1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

   // Common header included in all CatalogService requests.
   2: optional TCatalogServiceRequestHeader header

   3: required JniCatalog.TDdlType ddl_type

   // Parameters for ALTER TABLE
   4: optional JniCatalog.TAlterTableParams alter_table_params

   // Parameters for ALTER VIEW
   5: optional JniCatalog.TCreateOrAlterViewParams alter_view_params

   // Parameters for CREATE DATABASE
   6: optional JniCatalog.TCreateDbParams create_db_params

   // Parameters for CREATE TABLE
   7: optional JniCatalog.TCreateTableParams create_table_params

   // Parameters for CREATE TABLE LIKE
   8: optional JniCatalog.TCreateTableLikeParams create_table_like_params

   // Parameters for CREATE VIEW
   9: optional JniCatalog.TCreateOrAlterViewParams create_view_params

   // Parameters for CREATE FUNCTION
   10: optional JniCatalog.TCreateFunctionParams create_fn_params

   // Parameters for DROP DATABASE
   11: optional JniCatalog.TDropDbParams drop_db_params

   // Parameters for DROP TABLE/VIEW
   12: optional JniCatalog.TDropTableOrViewParams drop_table_or_view_params

   // Parameters for TRUNCATE TABLE
   13: optional JniCatalog.TTruncateParams truncate_params

   // Parameters for DROP FUNCTION
   14: optional JniCatalog.TDropFunctionParams drop_fn_params

   // Parameters for COMPUTE STATS
   15: optional JniCatalog.TComputeStatsParams compute_stats_params

   // Parameters for CREATE DATA SOURCE
   16: optional JniCatalog.TCreateDataSourceParams create_data_source_params

   // Parameters for DROP DATA SOURCE
   17: optional JniCatalog.TDropDataSourceParams drop_data_source_params

   // Parameters for DROP STATS
   18: optional JniCatalog.TDropStatsParams drop_stats_params

   // Parameters for CREATE/DROP ROLE
   19: optional JniCatalog.TCreateDropRoleParams create_drop_role_params

   // Parameters for GRANT/REVOKE ROLE
   20: optional JniCatalog.TGrantRevokeRoleParams grant_revoke_role_params

   // Parameters for GRANT/REVOKE privilege
   21: optional JniCatalog.TGrantRevokePrivParams grant_revoke_priv_params

   // True if SYNC_DDL is set in query options
   22: required bool sync_ddl

   // Parameters for COMMENT ON
   23: optional JniCatalog.TCommentOnParams comment_on_params

   // Parameters for ALTER DATABASE
   24: optional JniCatalog.TAlterDbParams alter_db_params
 }

 // Response from executing a TDdlExecRequest
 struct TDdlExecResponse {
   1: required TCatalogUpdateResult result

   // Set only for CREATE TABLE AS SELECT statements. Will be true iff the statement
   // resulted in a new table being created in the Metastore. This is used to
   // determine if a CREATE TABLE IF NOT EXISTS AS SELECT ... actually creates a new
   // table or whether creation was skipped because the table already existed, in which
   // case this flag would be false
   2: optional bool new_table_created;

   // Result of DDL operation to be returned to the client. Currently only set
   // by COMPUTE STATS and ALTER TABLE.
   3: optional Results.TResultSet result_set
 }

 // Updates the metastore with new partition information and returns a response
 // with details on the result of the operation. Used to add partitions after executing
 // DML operations, and could potentially be used in the future to update column stats
 // after DML operations.
 // TODO: Rename this struct to something more descriptive.
 struct TUpdateCatalogRequest {
   1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

   // True if SYNC_DDL is set in query options.
   2: required bool sync_ddl

   // Common header included in all CatalogService requests.
   3: optional TCatalogServiceRequestHeader header

   // Unqualified name of the table to change
   4: required string target_table;

   // Database that the table belongs to
   5: required string db_name;

   // List of partitions that are new and need to be created. May
   // include the root partition (represented by the empty string).
   6: required set<string> created_partitions;
 }

 // Response from a TUpdateCatalogRequest
 struct TUpdateCatalogResponse {
   1: required TCatalogUpdateResult result
 }

 // Parameters of REFRESH/INVALIDATE METADATA commands
 struct TResetMetadataRequest {
   1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

   // Common header included in all CatalogService requests.
   2: optional TCatalogServiceRequestHeader header

   // If true, refresh. Otherwise, invalidate metadata
   3: required bool is_refresh

   // Fully qualified name of the table to refresh or invalidate; not set if invalidating
   // the entire catalog
   4: optional CatalogObjects.TTableName table_name

   // If set, refreshes the specified partition, otherwise
   // refreshes the whole table
   5: optional list<CatalogObjects.TPartitionKeyValue> partition_spec

   // If set, refreshes functions in the specified database.
   6: optional string db_name

   // True if SYNC_DDL is set in query options
   7: required bool sync_ddl
 }

 // Response from TResetMetadataRequest
 struct TResetMetadataResponse {
   1: required TCatalogUpdateResult result
 }

 // Request to GetFunctions()
 struct TGetFunctionsRequest {
   1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

   // Common header included in all CatalogService requests.
   3: optional TCatalogServiceRequestHeader header

   // The parent database name.
   2: optional string db_name;
 }

 // Response a call to GetFunctions()
 struct TGetFunctionsResponse {
   // The status of the operation, OK if the operation was successful.
   1: optional Status.TStatus status

   // List of functions returned to the caller. Functions are not returned in a
   // defined order.
   2: optional list<Types.TFunction> functions;
 }

 // Selector for partial information about Catalog-scoped objects
 // (i.e. those that are not within a particular database or table).
 struct TCatalogInfoSelector {
   1: bool want_db_names
   // TODO(todd): add objects like DataSources, etc.
 }

 // Returned info from a catalog request which selected items in
 // TCatalogInfoSelector.
 struct TPartialCatalogInfo {
   1: list<string> db_names
 }

 // Selector for partial information about a Table.
 struct TTableInfoSelector {
   // The response should include the HMS table struct.
   1: bool want_hms_table

   // If set, the response should include information about the given list of
   // partitions. If this is unset, information about all partitions will be
   // returned, so long as at least one of the following 'want_partition_*'
   // flags is specified.
   //
   // If a partition ID is passed, but that partition does not exist in the
   // table, then an exception will be thrown. It is assumed that the partition
   // IDs passed here are a result of a prior successful call to fetch the partition
   // list of this table.
   //
   // NOTE: "unset" and "set to empty" are different -- "set to empty" causes
   // no partitions to be returned, whereas "unset" causes all partitions to be
   // returned, so long as one of the following 'want_partition_*' is set.
   2: optional list<i64> partition_ids

   // ... each such partition should include its name.
   3: bool want_partition_names

   // ... each such partition should include metadata (location, etc).
   4: bool want_partition_metadata

   // ... each such partition should include its file info
   5: bool want_partition_files

   // List of columns to fetch stats for.
   6: optional list<string> want_stats_for_column_names
 }

 // Returned information about a particular partition.
 struct TPartialPartitionInfo {
   1: required i64 id

   // Set if 'want_partition_names' was set in TTableInfoSelector.
   2: optional string name

   // Set if 'want_partition_metadata' was set in TTableInfoSelector.
   3: optional hive_metastore.Partition hms_partition

   // Set if 'want_partition_files' was set in TTableInfoSelector.
   4: optional list<CatalogObjects.THdfsFileDesc> file_descriptors
 }

 // Returned information about a Table, as selected by TTableInfoSelector.
 struct TPartialTableInfo {
   1: optional hive_metastore.Table hms_table

   // The partition metadata for the requested partitions.
   //
   // If explicit partitions were passed, then it is guaranteed that this list
   // is the same size and the same order as the requested list of IDs.
   //
   // See TPartialPartitionInfo for details on which fields will be set based
   // on the caller-provided selector.
   2: optional list<TPartialPartitionInfo> partitions

   3: optional list<hive_metastore.ColumnStatisticsObj> column_stats

   // Each TNetworkAddress is a datanode which contains blocks of a file in the table.
   // Used so that each THdfsFileBlock can just reference an index in this list rather
   // than duplicate the list of network address, which helps reduce memory usage.
   // Only used when partition files are fetched.
   7: optional list<Types.TNetworkAddress> network_addresses
 }

 // Selector for partial information about a Database.
 struct TDbInfoSelector {
   // The response should include the HMS Database object.
   1: bool want_hms_database
   // The response should include the list of table names in the DB.
   2: bool want_table_names
   // TODO(todd): function names
 }

 // Returned information about a Database, as selected by TDbInfoSelector.
 struct TPartialDbInfo {
   1: optional hive_metastore.Database hms_database
   2: optional list<string> table_names
 }

 // RPC request for GetPartialCatalogObject.
 struct TGetPartialCatalogObjectRequest {
   1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

   // A catalog object descriptor: a TCatalogObject with the object name and type fields
   // set.
   2: required CatalogObjects.TCatalogObject object_desc

   3: optional TTableInfoSelector table_info_selector
   4: optional TDbInfoSelector db_info_selector
   5: optional TCatalogInfoSelector catalog_info_selector
 }

 // RPC response for GetPartialCatalogObject.
 struct TGetPartialCatalogObjectResponse {
   // The status of the operation, OK if the operation was successful.
   // Unset indicates "OK".
   1: optional Status.TStatus status

   2: optional i64 object_version_number
   3: optional TPartialTableInfo table_info
   4: optional TPartialDbInfo db_info
   5: optional TPartialCatalogInfo catalog_info
 }


 // Request the complete metadata for a given catalog object. May trigger a metadata load
 // if the object is not already in the catalog cache.
 struct TGetCatalogObjectRequest {
   1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

   // Common header included in all CatalogService requests.
   3: optional TCatalogServiceRequestHeader header

   // A catalog object descriptor: a TCatalogObject with the object name and type fields
   // set.
   2: required CatalogObjects.TCatalogObject object_desc
 }

 // Response from TGetCatalogObjectRequest
 struct TGetCatalogObjectResponse {
   1: required CatalogObjects.TCatalogObject catalog_object
 }

 // Instructs the Catalog Server to prioritizing loading of metadata for the specified
 // catalog objects. Currently only used for controlling the priority of loading
 // tables/views since Db/Function metadata is loaded on startup.
 struct TPrioritizeLoadRequest {
   1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

   // Common header included in all CatalogService requests.
   2: optional TCatalogServiceRequestHeader header

   // A list of catalog objects descriptors for which to prioritize loading. A catalog
   // object descriptor is a TCatalogObject with only the object name and type fields set.
   3: required list<CatalogObjects.TCatalogObject> object_descs
 }

 struct TPrioritizeLoadResponse {
   // The status of the operation, OK if the operation was successful.
   1: required Status.TStatus status
 }

 // Request to perform a privilege check with the Sentry Service to determine
 // if the requesting user is a Sentry Service admin.
 struct TSentryAdminCheckRequest {
   1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

   // Common header included in all CatalogService requests.
   2: optional TCatalogServiceRequestHeader header
 }

 struct TSentryAdminCheckResponse {
   // Contains an error if the user does not have privileges to access the Sentry Service
   // or if the Sentry Service is unavailable. Returns OK if the operation was successful.
   1: optional Status.TStatus status
 }

 // The CatalogService API
 service CatalogService {
   // Executes a DDL request and returns details on the result of the operation.
   TDdlExecResponse ExecDdl(1: TDdlExecRequest req);

   // Gets the catalog object corresponding to the given request.
   TGetCatalogObjectResponse GetCatalogObject(1: TGetCatalogObjectRequest req);

   // Resets the Catalog metadata. Used to explicitly trigger reloading of the Hive
   // Metastore metadata and/or HDFS block location metadata.
   TResetMetadataResponse ResetMetadata(1: TResetMetadataRequest req);

   // Updates the metastore with new partition information and returns a response
   // with details on the result of the operation.
   TUpdateCatalogResponse UpdateCatalog(1: TUpdateCatalogRequest req);

   // Gets all user defined functions (aggregate and scalar) in the catalog matching
   // the parameters of TGetFunctionsRequest.
   TGetFunctionsResponse GetFunctions(1: TGetFunctionsRequest req);

   // Prioritize the loading of metadata for the CatalogObjects specified in the
   // TPrioritizeLoadRequest.
   TPrioritizeLoadResponse PrioritizeLoad(1: TPrioritizeLoadRequest req);

   // Performs a check with the Sentry Service to determine if the requesting user
   // is configured as an admin on the Sentry Service. This API may be removed in
   // the future and external clients should not rely on using it.
   // TODO: When Sentry Service has a better mechanism to perform these changes this API
   // should be deprecated.
   TSentryAdminCheckResponse SentryAdminCheck(1: TSentryAdminCheckRequest req);

   // Fetch partial information about some object in the catalog.
   TGetPartialCatalogObjectResponse GetPartialCatalogObject(
       1: TGetPartialCatalogObjectRequest req);
 }
	// 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.

	namespace cpp impala
	namespace java org.apache.impala.thrift

	include "CatalogObjects.thrift"
	include "JniCatalog.thrift"
	include "Types.thrift"
	include "Status.thrift"
	include "Results.thrift"
	include "hive_metastore.thrift"

	// CatalogServer service API and related structs.

	enum CatalogServiceVersion {
	V1
	}

	// Common header included in all CatalogService requests.
	// TODO: The CatalogServiceVersion/protocol version should be part of the header.
	// This would require changes in BDR and break their compatibility story. We should
	// coordinate a joint change somewhere down the line.
	struct TCatalogServiceRequestHeader {
	// The effective user who submitted this request.
	1: optional string requesting_user
	}

	// Returns details on the result of an operation that updates the catalog. Information
	// returned includes the Status of the operations, the catalog version that will contain
	// the update, and the catalog service ID. If SYNC_DDL was set in the query options, it
	// also returns the version of the catalog update that this operation must wait for
	// before returning the response to the client.
	struct TCatalogUpdateResult {
	// The CatalogService service ID this result came from.
	1: required Types.TUniqueId catalog_service_id

	// The Catalog version that will contain this update.
	2: required i64 version

	// The status of the operation, OK if the operation was successful.
	3: required Status.TStatus status

	// True if this is a result of an INVALIDATE METADATA operation.
	4: required bool is_invalidate

	// The resulting TCatalogObjects that were added or modified, if applicable.
	5: optional list<CatalogObjects.TCatalogObject> updated_catalog_objects

	// The resulting TCatalogObjects that were removed, if applicable.
	6: optional list<CatalogObjects.TCatalogObject> removed_catalog_objects
	}

	// Request for executing a DDL operation (CREATE, ALTER, DROP).
	struct TDdlExecRequest {
	1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

	// Common header included in all CatalogService requests.
	2: optional TCatalogServiceRequestHeader header

	3: required JniCatalog.TDdlType ddl_type

	// Parameters for ALTER TABLE
	4: optional JniCatalog.TAlterTableParams alter_table_params

	// Parameters for ALTER VIEW
	5: optional JniCatalog.TCreateOrAlterViewParams alter_view_params

	// Parameters for CREATE DATABASE
	6: optional JniCatalog.TCreateDbParams create_db_params

	// Parameters for CREATE TABLE
	7: optional JniCatalog.TCreateTableParams create_table_params

	// Parameters for CREATE TABLE LIKE
	8: optional JniCatalog.TCreateTableLikeParams create_table_like_params

	// Parameters for CREATE VIEW
	9: optional JniCatalog.TCreateOrAlterViewParams create_view_params

	// Parameters for CREATE FUNCTION
	10: optional JniCatalog.TCreateFunctionParams create_fn_params

	// Parameters for DROP DATABASE
	11: optional JniCatalog.TDropDbParams drop_db_params

	// Parameters for DROP TABLE/VIEW
	12: optional JniCatalog.TDropTableOrViewParams drop_table_or_view_params

	// Parameters for TRUNCATE TABLE
	13: optional JniCatalog.TTruncateParams truncate_params

	// Parameters for DROP FUNCTION
	14: optional JniCatalog.TDropFunctionParams drop_fn_params

	// Parameters for COMPUTE STATS
	15: optional JniCatalog.TComputeStatsParams compute_stats_params

	// Parameters for CREATE DATA SOURCE
	16: optional JniCatalog.TCreateDataSourceParams create_data_source_params

	// Parameters for DROP DATA SOURCE
	17: optional JniCatalog.TDropDataSourceParams drop_data_source_params

	// Parameters for DROP STATS
	18: optional JniCatalog.TDropStatsParams drop_stats_params

	// Parameters for CREATE/DROP ROLE
	19: optional JniCatalog.TCreateDropRoleParams create_drop_role_params

	// Parameters for GRANT/REVOKE ROLE
	20: optional JniCatalog.TGrantRevokeRoleParams grant_revoke_role_params

	// Parameters for GRANT/REVOKE privilege
	21: optional JniCatalog.TGrantRevokePrivParams grant_revoke_priv_params

	// True if SYNC_DDL is set in query options
	22: required bool sync_ddl

	// Parameters for COMMENT ON
	23: optional JniCatalog.TCommentOnParams comment_on_params

	// Parameters for ALTER DATABASE
	24: optional JniCatalog.TAlterDbParams alter_db_params
	}

	// Response from executing a TDdlExecRequest
	struct TDdlExecResponse {
	1: required TCatalogUpdateResult result

	// Set only for CREATE TABLE AS SELECT statements. Will be true iff the statement
	// resulted in a new table being created in the Metastore. This is used to
	// determine if a CREATE TABLE IF NOT EXISTS AS SELECT ... actually creates a new
	// table or whether creation was skipped because the table already existed, in which
	// case this flag would be false
	2: optional bool new_table_created;

	// Result of DDL operation to be returned to the client. Currently only set
	// by COMPUTE STATS and ALTER TABLE.
	3: optional Results.TResultSet result_set
	}

	// Updates the metastore with new partition information and returns a response
	// with details on the result of the operation. Used to add partitions after executing
	// DML operations, and could potentially be used in the future to update column stats
	// after DML operations.
	// TODO: Rename this struct to something more descriptive.
	struct TUpdateCatalogRequest {
	1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

	// True if SYNC_DDL is set in query options.
	2: required bool sync_ddl

	// Common header included in all CatalogService requests.
	3: optional TCatalogServiceRequestHeader header

	// Unqualified name of the table to change
	4: required string target_table;

	// Database that the table belongs to
	5: required string db_name;

	// List of partitions that are new and need to be created. May
	// include the root partition (represented by the empty string).
	6: required set<string> created_partitions;
	}

	// Response from a TUpdateCatalogRequest
	struct TUpdateCatalogResponse {
	1: required TCatalogUpdateResult result
	}

	// Parameters of REFRESH/INVALIDATE METADATA commands
	struct TResetMetadataRequest {
	1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

	// Common header included in all CatalogService requests.
	2: optional TCatalogServiceRequestHeader header

	// If true, refresh. Otherwise, invalidate metadata
	3: required bool is_refresh

	// Fully qualified name of the table to refresh or invalidate; not set if invalidating
	// the entire catalog
	4: optional CatalogObjects.TTableName table_name

	// If set, refreshes the specified partition, otherwise
	// refreshes the whole table
	5: optional list<CatalogObjects.TPartitionKeyValue> partition_spec

	// If set, refreshes functions in the specified database.
	6: optional string db_name

	// True if SYNC_DDL is set in query options
	7: required bool sync_ddl
	}

	// Response from TResetMetadataRequest
	struct TResetMetadataResponse {
	1: required TCatalogUpdateResult result
	}

	// Request to GetFunctions()
	struct TGetFunctionsRequest {
	1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

	// Common header included in all CatalogService requests.
	3: optional TCatalogServiceRequestHeader header

	// The parent database name.
	2: optional string db_name;
	}

	// Response a call to GetFunctions()
	struct TGetFunctionsResponse {
	// The status of the operation, OK if the operation was successful.
	1: optional Status.TStatus status

	// List of functions returned to the caller. Functions are not returned in a
	// defined order.
	2: optional list<Types.TFunction> functions;
	}

	// Selector for partial information about Catalog-scoped objects
	// (i.e. those that are not within a particular database or table).
	struct TCatalogInfoSelector {
	1: bool want_db_names
	// TODO(todd): add objects like DataSources, etc.
	}

	// Returned info from a catalog request which selected items in
	// TCatalogInfoSelector.
	struct TPartialCatalogInfo {
	1: list<string> db_names
	}

	// Selector for partial information about a Table.
	struct TTableInfoSelector {
	// The response should include the HMS table struct.
	1: bool want_hms_table

	// If set, the response should include information about the given list of
	// partitions. If this is unset, information about all partitions will be
	// returned, so long as at least one of the following 'want_partition_*'
	// flags is specified.
	//
	// If a partition ID is passed, but that partition does not exist in the
	// table, then an exception will be thrown. It is assumed that the partition
	// IDs passed here are a result of a prior successful call to fetch the partition
	// list of this table.
	//
	// NOTE: "unset" and "set to empty" are different -- "set to empty" causes
	// no partitions to be returned, whereas "unset" causes all partitions to be
	// returned, so long as one of the following 'want_partition_*' is set.
	2: optional list<i64> partition_ids

	// ... each such partition should include its name.
	3: bool want_partition_names

	// ... each such partition should include metadata (location, etc).
	4: bool want_partition_metadata

	// ... each such partition should include its file info
	5: bool want_partition_files

	// List of columns to fetch stats for.
	6: optional list<string> want_stats_for_column_names
	}

	// Returned information about a particular partition.
	struct TPartialPartitionInfo {
	1: required i64 id

	// Set if 'want_partition_names' was set in TTableInfoSelector.
	2: optional string name

	// Set if 'want_partition_metadata' was set in TTableInfoSelector.
	3: optional hive_metastore.Partition hms_partition

	// Set if 'want_partition_files' was set in TTableInfoSelector.
	4: optional list<CatalogObjects.THdfsFileDesc> file_descriptors
	}

	// Returned information about a Table, as selected by TTableInfoSelector.
	struct TPartialTableInfo {
	1: optional hive_metastore.Table hms_table

	// The partition metadata for the requested partitions.
	//
	// If explicit partitions were passed, then it is guaranteed that this list
	// is the same size and the same order as the requested list of IDs.
	//
	// See TPartialPartitionInfo for details on which fields will be set based
	// on the caller-provided selector.
	2: optional list<TPartialPartitionInfo> partitions

	3: optional list<hive_metastore.ColumnStatisticsObj> column_stats

	// Each TNetworkAddress is a datanode which contains blocks of a file in the table.
	// Used so that each THdfsFileBlock can just reference an index in this list rather
	// than duplicate the list of network address, which helps reduce memory usage.
	// Only used when partition files are fetched.
	7: optional list<Types.TNetworkAddress> network_addresses
	}

	// Selector for partial information about a Database.
	struct TDbInfoSelector {
	// The response should include the HMS Database object.
	1: bool want_hms_database
	// The response should include the list of table names in the DB.
	2: bool want_table_names
	// TODO(todd): function names
	}

	// Returned information about a Database, as selected by TDbInfoSelector.
	struct TPartialDbInfo {
	1: optional hive_metastore.Database hms_database
	2: optional list<string> table_names
	}

	// RPC request for GetPartialCatalogObject.
	struct TGetPartialCatalogObjectRequest {
	1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

	// A catalog object descriptor: a TCatalogObject with the object name and type fields
	// set.
	2: required CatalogObjects.TCatalogObject object_desc

	3: optional TTableInfoSelector table_info_selector
	4: optional TDbInfoSelector db_info_selector
	5: optional TCatalogInfoSelector catalog_info_selector
	}

	// RPC response for GetPartialCatalogObject.
	struct TGetPartialCatalogObjectResponse {
	// The status of the operation, OK if the operation was successful.
	// Unset indicates "OK".
	1: optional Status.TStatus status

	2: optional i64 object_version_number
	3: optional TPartialTableInfo table_info
	4: optional TPartialDbInfo db_info
	5: optional TPartialCatalogInfo catalog_info
	}


	// Request the complete metadata for a given catalog object. May trigger a metadata load
	// if the object is not already in the catalog cache.
	struct TGetCatalogObjectRequest {
	1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

	// Common header included in all CatalogService requests.
	3: optional TCatalogServiceRequestHeader header

	// A catalog object descriptor: a TCatalogObject with the object name and type fields
	// set.
	2: required CatalogObjects.TCatalogObject object_desc
	}

	// Response from TGetCatalogObjectRequest
	struct TGetCatalogObjectResponse {
	1: required CatalogObjects.TCatalogObject catalog_object
	}

	// Instructs the Catalog Server to prioritizing loading of metadata for the specified
	// catalog objects. Currently only used for controlling the priority of loading
	// tables/views since Db/Function metadata is loaded on startup.
	struct TPrioritizeLoadRequest {
	1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

	// Common header included in all CatalogService requests.
	2: optional TCatalogServiceRequestHeader header

	// A list of catalog objects descriptors for which to prioritize loading. A catalog
	// object descriptor is a TCatalogObject with only the object name and type fields set.
	3: required list<CatalogObjects.TCatalogObject> object_descs
	}

	struct TPrioritizeLoadResponse {
	// The status of the operation, OK if the operation was successful.
	1: required Status.TStatus status
	}

	// Request to perform a privilege check with the Sentry Service to determine
	// if the requesting user is a Sentry Service admin.
	struct TSentryAdminCheckRequest {
	1: required CatalogServiceVersion protocol_version = CatalogServiceVersion.V1

	// Common header included in all CatalogService requests.
	2: optional TCatalogServiceRequestHeader header
	}

	struct TSentryAdminCheckResponse {
	// Contains an error if the user does not have privileges to access the Sentry Service
	// or if the Sentry Service is unavailable. Returns OK if the operation was successful.
	1: optional Status.TStatus status
	}

	// The CatalogService API
	service CatalogService {
	// Executes a DDL request and returns details on the result of the operation.
	TDdlExecResponse ExecDdl(1: TDdlExecRequest req);

	// Gets the catalog object corresponding to the given request.
	TGetCatalogObjectResponse GetCatalogObject(1: TGetCatalogObjectRequest req);

	// Resets the Catalog metadata. Used to explicitly trigger reloading of the Hive
	// Metastore metadata and/or HDFS block location metadata.
	TResetMetadataResponse ResetMetadata(1: TResetMetadataRequest req);

	// Updates the metastore with new partition information and returns a response
	// with details on the result of the operation.
	TUpdateCatalogResponse UpdateCatalog(1: TUpdateCatalogRequest req);

	// Gets all user defined functions (aggregate and scalar) in the catalog matching
	// the parameters of TGetFunctionsRequest.
	TGetFunctionsResponse GetFunctions(1: TGetFunctionsRequest req);

	// Prioritize the loading of metadata for the CatalogObjects specified in the
	// TPrioritizeLoadRequest.
	TPrioritizeLoadResponse PrioritizeLoad(1: TPrioritizeLoadRequest req);

	// Performs a check with the Sentry Service to determine if the requesting user
	// is configured as an admin on the Sentry Service. This API may be removed in
	// the future and external clients should not rely on using it.
	// TODO: When Sentry Service has a better mechanism to perform these changes this API
	// should be deprecated.
	TSentryAdminCheckResponse SentryAdminCheck(1: TSentryAdminCheckRequest req);

	// Fetch partial information about some object in the catalog.
	TGetPartialCatalogObjectResponse GetPartialCatalogObject(
	1: TGetPartialCatalogObjectRequest req);
	}