database_admin_client.h

// Copyright 2021 Google LLC
//
// Licensed 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
//
//      https://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.

// Generated by the Codegen C++ plugin.
// If you make any local changes, they will be lost.
// source: google/spanner/admin/database/v1/spanner_database_admin.proto

#ifndef GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_SPANNER_ADMIN_DATABASE_ADMIN_CLIENT_H
#define GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_SPANNER_ADMIN_DATABASE_ADMIN_CLIENT_H

#include "google/cloud/spanner/admin/database_admin_connection.h"
#include "google/cloud/future.h"
#include "google/cloud/iam_updater.h"
#include "google/cloud/options.h"
#include "google/cloud/polling_policy.h"
#include "google/cloud/status_or.h"
#include "google/cloud/version.h"
#include <google/longrunning/operations.grpc.pb.h>
#include <memory>

namespace google {
namespace cloud {
namespace spanner_admin {
GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_BEGIN

///
/// Cloud Spanner Database Admin API
///
/// The Cloud Spanner Database Admin API can be used to:
///   * create, drop, and list databases
///   * update the schema of pre-existing databases
///   * create, delete and list backups for a database
///   * restore a database from an existing backup
///
/// @par Equality
///
/// Instances of this class created via copy-construction or copy-assignment
/// always compare equal. Instances created with equal
/// `std::shared_ptr<*Connection>` objects compare equal. Objects that compare
/// equal share the same underlying resources.
///
/// @par Performance
///
/// Creating a new instance of this class is a relatively expensive operation,
/// new objects establish new connections to the service. In contrast,
/// copy-construction, move-construction, and the corresponding assignment
/// operations are relatively efficient as the copies share all underlying
/// resources.
///
/// @par Thread Safety
///
/// Concurrent access to different instances of this class, even if they compare
/// equal, is guaranteed to work. Two or more threads operating on the same
/// instance of this class is not guaranteed to work. Since copy-construction
/// and move-construction is a relatively efficient operation, consider using
/// such a copy when using this class from multiple threads.
///
class DatabaseAdminClient {
 public:
  explicit DatabaseAdminClient(
      std::shared_ptr<DatabaseAdminConnection> connection, Options opts = {});
  ~DatabaseAdminClient();

  ///@{
  /// @name Copy and move support
  DatabaseAdminClient(DatabaseAdminClient const&) = default;
  DatabaseAdminClient& operator=(DatabaseAdminClient const&) = default;
  DatabaseAdminClient(DatabaseAdminClient&&) = default;
  DatabaseAdminClient& operator=(DatabaseAdminClient&&) = default;
  ///@}

  ///@{
  /// @name Equality
  friend bool operator==(DatabaseAdminClient const& a,
                         DatabaseAdminClient const& b) {
    return a.connection_ == b.connection_;
  }
  friend bool operator!=(DatabaseAdminClient const& a,
                         DatabaseAdminClient const& b) {
    return !(a == b);
  }
  ///@}

  // clang-format off
  ///
  /// Lists Cloud Spanner databases.
  ///
  /// @param parent  Required. The instance whose databases should be listed.
  ///  Values are of the form `projects/<project>/instances/<instance>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.spanner.admin.database.v1.Database], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  /// [google.spanner.admin.database.v1.ListDatabasesRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L513}
  ///
  // clang-format on
  StreamRange<google::spanner::admin::database::v1::Database> ListDatabases(
      std::string const& parent, Options opts = {});

  // clang-format off
  ///
  /// Lists Cloud Spanner databases.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.ListDatabasesRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.spanner.admin.database.v1.Database], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  /// [google.spanner.admin.database.v1.ListDatabasesRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L513}
  ///
  // clang-format on
  StreamRange<google::spanner::admin::database::v1::Database> ListDatabases(
      google::spanner::admin::database::v1::ListDatabasesRequest request,
      Options opts = {});

  // clang-format off
  ///
  /// Creates a new Cloud Spanner database and starts to prepare it for serving.
  /// The returned [long-running operation][google.longrunning.Operation] will
  /// have a name of the format `<database_name>/operations/<operation_id>` and
  /// can be used to track preparation of the database. The
  /// [metadata][google.longrunning.Operation.metadata] field type is
  /// [CreateDatabaseMetadata][google.spanner.admin.database.v1.CreateDatabaseMetadata]. The
  /// [response][google.longrunning.Operation.response] field type is
  /// [Database][google.spanner.admin.database.v1.Database], if successful.
  ///
  /// @param parent  Required. The name of the instance that will serve the new database.
  ///  Values are of the form `projects/<project>/instances/<instance>`.
  /// @param create_statement  Required. A `CREATE DATABASE` statement, which specifies the ID of the
  ///  new database.  The database ID must conform to the regular expression
  ///  `[a-z][a-z0-9_\-]*[a-z0-9]` and be between 2 and 30 characters in length.
  ///  If the database ID is a reserved word or if it contains a hyphen, the
  ///  database ID must be enclosed in backticks (`` ` ``).
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Database] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.CreateDatabaseMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L579}
  /// [google.spanner.admin.database.v1.CreateDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L545}
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Database>>
  CreateDatabase(std::string const& parent, std::string const& create_statement,
                 Options opts = {});

  // clang-format off
  ///
  /// Creates a new Cloud Spanner database and starts to prepare it for serving.
  /// The returned [long-running operation][google.longrunning.Operation] will
  /// have a name of the format `<database_name>/operations/<operation_id>` and
  /// can be used to track preparation of the database. The
  /// [metadata][google.longrunning.Operation.metadata] field type is
  /// [CreateDatabaseMetadata][google.spanner.admin.database.v1.CreateDatabaseMetadata]. The
  /// [response][google.longrunning.Operation.response] field type is
  /// [Database][google.spanner.admin.database.v1.Database], if successful.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.CreateDatabaseRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Database] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.CreateDatabaseMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L579}
  /// [google.spanner.admin.database.v1.CreateDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L545}
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Database>>
  CreateDatabase(
      google::spanner::admin::database::v1::CreateDatabaseRequest const&
          request,
      Options opts = {});

  // clang-format off
  ///
  /// Gets the state of a Cloud Spanner database.
  ///
  /// @param name  Required. The name of the requested database. Values are of the form
  ///  `projects/<project>/instances/<instance>/databases/<database>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.spanner.admin.database.v1.Database])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  /// [google.spanner.admin.database.v1.GetDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L587}
  ///
  // clang-format on
  StatusOr<google::spanner::admin::database::v1::Database> GetDatabase(
      std::string const& name, Options opts = {});

  // clang-format off
  ///
  /// Gets the state of a Cloud Spanner database.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.GetDatabaseRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.spanner.admin.database.v1.Database])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  /// [google.spanner.admin.database.v1.GetDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L587}
  ///
  // clang-format on
  StatusOr<google::spanner::admin::database::v1::Database> GetDatabase(
      google::spanner::admin::database::v1::GetDatabaseRequest const& request,
      Options opts = {});

  // clang-format off
  ///
  /// Updates a Cloud Spanner database. The returned
  /// [long-running operation][google.longrunning.Operation] can be used to track
  /// the progress of updating the database. If the named database does not
  /// exist, returns `NOT_FOUND`.
  ///
  /// While the operation is pending:
  ///
  ///   * The database's
  ///     [reconciling][google.spanner.admin.database.v1.Database.reconciling]
  ///     field is set to true.
  ///   * Cancelling the operation is best-effort. If the cancellation succeeds,
  ///     the operation metadata's
  ///     [cancel_time][google.spanner.admin.database.v1.UpdateDatabaseMetadata.cancel_time]
  ///     is set, the updates are reverted, and the operation terminates with a
  ///     `CANCELLED` status.
  ///   * New UpdateDatabase requests will return a `FAILED_PRECONDITION` error
  ///     until the pending operation is done (returns successfully or with
  ///     error).
  ///   * Reading the database via the API continues to give the pre-request
  ///     values.
  ///
  /// Upon completion of the returned operation:
  ///
  ///   * The new values are in effect and readable via the API.
  ///   * The database's
  ///     [reconciling][google.spanner.admin.database.v1.Database.reconciling]
  ///     field becomes false.
  ///
  /// The returned [long-running operation][google.longrunning.Operation] will
  /// have a name of the format
  /// `projects/<project>/instances/<instance>/databases/<database>/operations/<operation_id>`
  /// and can be used to track the database modification. The
  /// [metadata][google.longrunning.Operation.metadata] field type is
  /// [UpdateDatabaseMetadata][google.spanner.admin.database.v1.UpdateDatabaseMetadata].
  /// The [response][google.longrunning.Operation.response] field type is
  /// [Database][google.spanner.admin.database.v1.Database], if successful.
  ///
  /// @param database  Required. The database to update.
  ///  The `name` field of the database is of the form
  ///  `projects/<project>/instances/<instance>/databases/<database>`.
  /// @param update_mask  Required. The list of fields to update. Currently, only
  ///  `enable_drop_protection` field can be updated.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Database] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  /// [google.spanner.admin.database.v1.Database.reconciling]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L509}
  /// [google.spanner.admin.database.v1.UpdateDatabaseMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L614}
  /// [google.spanner.admin.database.v1.UpdateDatabaseMetadata.cancel_time]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L626}
  /// [google.spanner.admin.database.v1.UpdateDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L600}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Database>>
  UpdateDatabase(google::spanner::admin::database::v1::Database const& database,
                 google::protobuf::FieldMask const& update_mask,
                 Options opts = {});

  // clang-format off
  ///
  /// Updates a Cloud Spanner database. The returned
  /// [long-running operation][google.longrunning.Operation] can be used to track
  /// the progress of updating the database. If the named database does not
  /// exist, returns `NOT_FOUND`.
  ///
  /// While the operation is pending:
  ///
  ///   * The database's
  ///     [reconciling][google.spanner.admin.database.v1.Database.reconciling]
  ///     field is set to true.
  ///   * Cancelling the operation is best-effort. If the cancellation succeeds,
  ///     the operation metadata's
  ///     [cancel_time][google.spanner.admin.database.v1.UpdateDatabaseMetadata.cancel_time]
  ///     is set, the updates are reverted, and the operation terminates with a
  ///     `CANCELLED` status.
  ///   * New UpdateDatabase requests will return a `FAILED_PRECONDITION` error
  ///     until the pending operation is done (returns successfully or with
  ///     error).
  ///   * Reading the database via the API continues to give the pre-request
  ///     values.
  ///
  /// Upon completion of the returned operation:
  ///
  ///   * The new values are in effect and readable via the API.
  ///   * The database's
  ///     [reconciling][google.spanner.admin.database.v1.Database.reconciling]
  ///     field becomes false.
  ///
  /// The returned [long-running operation][google.longrunning.Operation] will
  /// have a name of the format
  /// `projects/<project>/instances/<instance>/databases/<database>/operations/<operation_id>`
  /// and can be used to track the database modification. The
  /// [metadata][google.longrunning.Operation.metadata] field type is
  /// [UpdateDatabaseMetadata][google.spanner.admin.database.v1.UpdateDatabaseMetadata].
  /// The [response][google.longrunning.Operation.response] field type is
  /// [Database][google.spanner.admin.database.v1.Database], if successful.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.UpdateDatabaseRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Database] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  /// [google.spanner.admin.database.v1.Database.reconciling]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L509}
  /// [google.spanner.admin.database.v1.UpdateDatabaseMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L614}
  /// [google.spanner.admin.database.v1.UpdateDatabaseMetadata.cancel_time]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L626}
  /// [google.spanner.admin.database.v1.UpdateDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L600}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Database>>
  UpdateDatabase(
      google::spanner::admin::database::v1::UpdateDatabaseRequest const&
          request,
      Options opts = {});

  // clang-format off
  ///
  /// Updates the schema of a Cloud Spanner database by
  /// creating/altering/dropping tables, columns, indexes, etc. The returned
  /// [long-running operation][google.longrunning.Operation] will have a name of
  /// the format `<database_name>/operations/<operation_id>` and can be used to
  /// track execution of the schema change(s). The
  /// [metadata][google.longrunning.Operation.metadata] field type is
  /// [UpdateDatabaseDdlMetadata][google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata].  The operation has no response.
  ///
  /// @param database  Required. The database to update.
  /// @param statements  Required. DDL statements to be applied to the database.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L681}
  /// [google.spanner.admin.database.v1.UpdateDatabaseDdlRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L645}
  ///
  // clang-format on
  future<
      StatusOr<google::spanner::admin::database::v1::UpdateDatabaseDdlMetadata>>
  UpdateDatabaseDdl(std::string const& database,
                    std::vector<std::string> const& statements,
                    Options opts = {});

  // clang-format off
  ///
  /// Updates the schema of a Cloud Spanner database by
  /// creating/altering/dropping tables, columns, indexes, etc. The returned
  /// [long-running operation][google.longrunning.Operation] will have a name of
  /// the format `<database_name>/operations/<operation_id>` and can be used to
  /// track execution of the schema change(s). The
  /// [metadata][google.longrunning.Operation.metadata] field type is
  /// [UpdateDatabaseDdlMetadata][google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata].  The operation has no response.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.UpdateDatabaseDdlRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L681}
  /// [google.spanner.admin.database.v1.UpdateDatabaseDdlRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L645}
  ///
  // clang-format on
  future<
      StatusOr<google::spanner::admin::database::v1::UpdateDatabaseDdlMetadata>>
  UpdateDatabaseDdl(
      google::spanner::admin::database::v1::UpdateDatabaseDdlRequest const&
          request,
      Options opts = {});

  // clang-format off
  ///
  /// Drops (aka deletes) a Cloud Spanner database.
  /// Completed backups for the database will be retained according to their
  /// `expire_time`.
  /// Note: Cloud Spanner might continue to accept requests for a few seconds
  /// after the database has been deleted.
  ///
  /// @param database  Required. The database to be dropped.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [`Status`] object. If the request failed, the
  ///     status contains the details of the failure.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.DropDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L713}
  ///
  // clang-format on
  Status DropDatabase(std::string const& database, Options opts = {});

  // clang-format off
  ///
  /// Drops (aka deletes) a Cloud Spanner database.
  /// Completed backups for the database will be retained according to their
  /// `expire_time`.
  /// Note: Cloud Spanner might continue to accept requests for a few seconds
  /// after the database has been deleted.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.DropDatabaseRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [`Status`] object. If the request failed, the
  ///     status contains the details of the failure.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.DropDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L713}
  ///
  // clang-format on
  Status DropDatabase(
      google::spanner::admin::database::v1::DropDatabaseRequest const& request,
      Options opts = {});

  // clang-format off
  ///
  /// Returns the schema of a Cloud Spanner database as a list of formatted
  /// DDL statements. This method does not show pending schema updates, those may
  /// be queried using the [Operations][google.longrunning.Operations] API.
  ///
  /// @param database  Required. The database whose schema we wish to get.
  ///  Values are of the form
  ///  `projects/<project>/instances/<instance>/databases/<database>`
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.spanner.admin.database.v1.GetDatabaseDdlResponse])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operations]: @googleapis_reference_link{google/longrunning/operations.proto#L54}
  /// [google.spanner.admin.database.v1.GetDatabaseDdlRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L724}
  /// [google.spanner.admin.database.v1.GetDatabaseDdlResponse]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L737}
  ///
  // clang-format on
  StatusOr<google::spanner::admin::database::v1::GetDatabaseDdlResponse>
  GetDatabaseDdl(std::string const& database, Options opts = {});

  // clang-format off
  ///
  /// Returns the schema of a Cloud Spanner database as a list of formatted
  /// DDL statements. This method does not show pending schema updates, those may
  /// be queried using the [Operations][google.longrunning.Operations] API.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.GetDatabaseDdlRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.spanner.admin.database.v1.GetDatabaseDdlResponse])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operations]: @googleapis_reference_link{google/longrunning/operations.proto#L54}
  /// [google.spanner.admin.database.v1.GetDatabaseDdlRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L724}
  /// [google.spanner.admin.database.v1.GetDatabaseDdlResponse]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L737}
  ///
  // clang-format on
  StatusOr<google::spanner::admin::database::v1::GetDatabaseDdlResponse>
  GetDatabaseDdl(
      google::spanner::admin::database::v1::GetDatabaseDdlRequest const&
          request,
      Options opts = {});

  // clang-format off
  ///
  /// Sets the access control policy on a database or backup resource.
  /// Replaces any existing policy.
  ///
  /// Authorization requires `spanner.databases.setIamPolicy`
  /// permission on [resource][google.iam.v1.SetIamPolicyRequest.resource].
  /// For backups, authorization requires `spanner.backups.setIamPolicy`
  /// permission on [resource][google.iam.v1.SetIamPolicyRequest.resource].
  ///
  /// @param resource  REQUIRED: The resource for which the policy is being specified.
  ///  See the operation documentation for the appropriate value for this field.
  /// @param policy  REQUIRED: The complete policy to be applied to the `resource`. The size of
  ///  the policy is limited to a few 10s of KB. An empty policy is a
  ///  valid policy but certain Cloud Platform services (such as Projects)
  ///  might reject them.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.iam.v1.Policy])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.iam.v1.Policy]: @googleapis_reference_link{google/iam/v1/policy.proto#L98}
  /// [google.iam.v1.SetIamPolicyRequest]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L101}
  /// [google.iam.v1.SetIamPolicyRequest.resource]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L104}
  ///
  // clang-format on
  StatusOr<google::iam::v1::Policy> SetIamPolicy(
      std::string const& resource, google::iam::v1::Policy const& policy,
      Options opts = {});

  /**
   * Updates the IAM policy for @p resource using an optimistic concurrency
   * control loop.
   *
   * The loop fetches the current policy for @p resource, and passes it to @p
   * updater, which should return the new policy. This new policy should use the
   * current etag so that the read-modify-write cycle can detect races and rerun
   * the update when there is a mismatch. If the new policy does not have an
   * etag, the existing policy will be blindly overwritten. If @p updater does
   * not yield a policy, the control loop is terminated and kCancelled is
   * returned.
   *
   * @param resource  Required. The resource for which the policy is being
   * specified. See the operation documentation for the appropriate value for
   * this field.
   * @param updater  Required. Functor to map the current policy to a new one.
   * @param opts  Optional. Override the class-level options, such as retry and
   *    backoff policies.
   * @return google::iam::v1::Policy
   */
  StatusOr<google::iam::v1::Policy> SetIamPolicy(std::string const& resource,
                                                 IamUpdater const& updater,
                                                 Options opts = {});

  // clang-format off
  ///
  /// Sets the access control policy on a database or backup resource.
  /// Replaces any existing policy.
  ///
  /// Authorization requires `spanner.databases.setIamPolicy`
  /// permission on [resource][google.iam.v1.SetIamPolicyRequest.resource].
  /// For backups, authorization requires `spanner.backups.setIamPolicy`
  /// permission on [resource][google.iam.v1.SetIamPolicyRequest.resource].
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.iam.v1.SetIamPolicyRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.iam.v1.Policy])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.iam.v1.Policy]: @googleapis_reference_link{google/iam/v1/policy.proto#L98}
  /// [google.iam.v1.SetIamPolicyRequest]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L101}
  /// [google.iam.v1.SetIamPolicyRequest.resource]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L104}
  ///
  // clang-format on
  StatusOr<google::iam::v1::Policy> SetIamPolicy(
      google::iam::v1::SetIamPolicyRequest const& request, Options opts = {});

  // clang-format off
  ///
  /// Gets the access control policy for a database or backup resource.
  /// Returns an empty policy if a database or backup exists but does not have a
  /// policy set.
  ///
  /// Authorization requires `spanner.databases.getIamPolicy` permission on
  /// [resource][google.iam.v1.GetIamPolicyRequest.resource].
  /// For backups, authorization requires `spanner.backups.getIamPolicy`
  /// permission on [resource][google.iam.v1.GetIamPolicyRequest.resource].
  ///
  /// @param resource  REQUIRED: The resource for which the policy is being requested.
  ///  See the operation documentation for the appropriate value for this field.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.iam.v1.Policy])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.iam.v1.GetIamPolicyRequest]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L123}
  /// [google.iam.v1.GetIamPolicyRequest.resource]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L126}
  /// [google.iam.v1.Policy]: @googleapis_reference_link{google/iam/v1/policy.proto#L98}
  ///
  // clang-format on
  StatusOr<google::iam::v1::Policy> GetIamPolicy(std::string const& resource,
                                                 Options opts = {});

  // clang-format off
  ///
  /// Gets the access control policy for a database or backup resource.
  /// Returns an empty policy if a database or backup exists but does not have a
  /// policy set.
  ///
  /// Authorization requires `spanner.databases.getIamPolicy` permission on
  /// [resource][google.iam.v1.GetIamPolicyRequest.resource].
  /// For backups, authorization requires `spanner.backups.getIamPolicy`
  /// permission on [resource][google.iam.v1.GetIamPolicyRequest.resource].
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.iam.v1.GetIamPolicyRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.iam.v1.Policy])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.iam.v1.GetIamPolicyRequest]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L123}
  /// [google.iam.v1.GetIamPolicyRequest.resource]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L126}
  /// [google.iam.v1.Policy]: @googleapis_reference_link{google/iam/v1/policy.proto#L98}
  ///
  // clang-format on
  StatusOr<google::iam::v1::Policy> GetIamPolicy(
      google::iam::v1::GetIamPolicyRequest const& request, Options opts = {});

  // clang-format off
  ///
  /// Returns permissions that the caller has on the specified database or backup
  /// resource.
  ///
  /// Attempting this RPC on a non-existent Cloud Spanner database will
  /// result in a NOT_FOUND error if the user has
  /// `spanner.databases.list` permission on the containing Cloud
  /// Spanner instance. Otherwise returns an empty set of permissions.
  /// Calling this method on a backup that does not exist will
  /// result in a NOT_FOUND error if the user has
  /// `spanner.backups.list` permission on the containing instance.
  ///
  /// @param resource  REQUIRED: The resource for which the policy detail is being requested.
  ///  See the operation documentation for the appropriate value for this field.
  /// @param permissions  The set of permissions to check for the `resource`. Permissions with
  ///  wildcards (such as '*' or 'storage.*') are not allowed. For more
  ///  information see
  ///  [IAM Overview](https://cloud.google.com/iam/docs/overview#permissions).
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.iam.v1.TestIamPermissionsResponse])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.iam.v1.TestIamPermissionsRequest]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L136}
  /// [google.iam.v1.TestIamPermissionsResponse]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L151}
  ///
  // clang-format on
  StatusOr<google::iam::v1::TestIamPermissionsResponse> TestIamPermissions(
      std::string const& resource, std::vector<std::string> const& permissions,
      Options opts = {});

  // clang-format off
  ///
  /// Returns permissions that the caller has on the specified database or backup
  /// resource.
  ///
  /// Attempting this RPC on a non-existent Cloud Spanner database will
  /// result in a NOT_FOUND error if the user has
  /// `spanner.databases.list` permission on the containing Cloud
  /// Spanner instance. Otherwise returns an empty set of permissions.
  /// Calling this method on a backup that does not exist will
  /// result in a NOT_FOUND error if the user has
  /// `spanner.backups.list` permission on the containing instance.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.iam.v1.TestIamPermissionsRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.iam.v1.TestIamPermissionsResponse])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.iam.v1.TestIamPermissionsRequest]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L136}
  /// [google.iam.v1.TestIamPermissionsResponse]: @googleapis_reference_link{google/iam/v1/iam_policy.proto#L151}
  ///
  // clang-format on
  StatusOr<google::iam::v1::TestIamPermissionsResponse> TestIamPermissions(
      google::iam::v1::TestIamPermissionsRequest const& request,
      Options opts = {});

  // clang-format off
  ///
  /// Starts creating a new Cloud Spanner Backup.
  /// The returned backup [long-running operation][google.longrunning.Operation]
  /// will have a name of the format
  /// `projects/<project>/instances/<instance>/backups/<backup>/operations/<operation_id>`
  /// and can be used to track creation of the backup. The
  /// [metadata][google.longrunning.Operation.metadata] field type is
  /// [CreateBackupMetadata][google.spanner.admin.database.v1.CreateBackupMetadata]. The
  /// [response][google.longrunning.Operation.response] field type is
  /// [Backup][google.spanner.admin.database.v1.Backup], if successful. Cancelling the returned operation will stop the
  /// creation and delete the backup.
  /// There can be only one pending backup creation per database. Backup creation
  /// of different databases can run concurrently.
  ///
  /// @param parent  Required. The name of the instance in which the backup will be
  ///  created. This must be the same instance that contains the database the
  ///  backup will be created from. The backup will be stored in the
  ///  location(s) specified in the instance configuration of this
  ///  instance. Values are of the form
  ///  `projects/<project>/instances/<instance>`.
  /// @param backup  Required. The backup to create.
  /// @param backup_id  Required. The id of the backup to be created. The `backup_id` appended to
  ///  `parent` forms the full backup name of the form
  ///  `projects/<project>/instances/<instance>/backups/<backup_id>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Backup] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.CreateBackupMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L178}
  /// [google.spanner.admin.database.v1.CreateBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L146}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Backup>> CreateBackup(
      std::string const& parent,
      google::spanner::admin::database::v1::Backup const& backup,
      std::string const& backup_id, Options opts = {});

  // clang-format off
  ///
  /// Starts creating a new Cloud Spanner Backup.
  /// The returned backup [long-running operation][google.longrunning.Operation]
  /// will have a name of the format
  /// `projects/<project>/instances/<instance>/backups/<backup>/operations/<operation_id>`
  /// and can be used to track creation of the backup. The
  /// [metadata][google.longrunning.Operation.metadata] field type is
  /// [CreateBackupMetadata][google.spanner.admin.database.v1.CreateBackupMetadata]. The
  /// [response][google.longrunning.Operation.response] field type is
  /// [Backup][google.spanner.admin.database.v1.Backup], if successful. Cancelling the returned operation will stop the
  /// creation and delete the backup.
  /// There can be only one pending backup creation per database. Backup creation
  /// of different databases can run concurrently.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.CreateBackupRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Backup] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.CreateBackupMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L178}
  /// [google.spanner.admin.database.v1.CreateBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L146}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Backup>> CreateBackup(
      google::spanner::admin::database::v1::CreateBackupRequest const& request,
      Options opts = {});

  // clang-format off
  ///
  /// Starts copying a Cloud Spanner Backup.
  /// The returned backup [long-running operation][google.longrunning.Operation]
  /// will have a name of the format
  /// `projects/<project>/instances/<instance>/backups/<backup>/operations/<operation_id>`
  /// and can be used to track copying of the backup. The operation is associated
  /// with the destination backup.
  /// The [metadata][google.longrunning.Operation.metadata] field type is
  /// [CopyBackupMetadata][google.spanner.admin.database.v1.CopyBackupMetadata].
  /// The [response][google.longrunning.Operation.response] field type is
  /// [Backup][google.spanner.admin.database.v1.Backup], if successful. Cancelling the returned operation will stop the
  /// copying and delete the backup.
  /// Concurrent CopyBackup requests can run on the same source backup.
  ///
  /// @param parent  Required. The name of the destination instance that will contain the backup copy.
  ///  Values are of the form: `projects/<project>/instances/<instance>`.
  /// @param backup_id  Required. The id of the backup copy.
  ///  The `backup_id` appended to `parent` forms the full backup_uri of the form
  ///  `projects/<project>/instances/<instance>/backups/<backup>`.
  /// @param source_backup  Required. The source backup to be copied.
  ///  The source backup needs to be in READY state for it to be copied.
  ///  Once CopyBackup is in progress, the source backup cannot be deleted or
  ///  cleaned up on expiration until CopyBackup is finished.
  ///  Values are of the form:
  ///  `projects/<project>/instances/<instance>/backups/<backup>`.
  /// @param expire_time  Required. The expiration time of the backup in microsecond granularity.
  ///  The expiration time must be at least 6 hours and at most 366 days
  ///  from the `create_time` of the source backup. Once the `expire_time` has
  ///  passed, the backup is eligible to be automatically deleted by Cloud Spanner
  ///  to free the resources used by the backup.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Backup] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.CopyBackupMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L254}
  /// [google.spanner.admin.database.v1.CopyBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L209}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Backup>> CopyBackup(
      std::string const& parent, std::string const& backup_id,
      std::string const& source_backup,
      google::protobuf::Timestamp const& expire_time, Options opts = {});

  // clang-format off
  ///
  /// Starts copying a Cloud Spanner Backup.
  /// The returned backup [long-running operation][google.longrunning.Operation]
  /// will have a name of the format
  /// `projects/<project>/instances/<instance>/backups/<backup>/operations/<operation_id>`
  /// and can be used to track copying of the backup. The operation is associated
  /// with the destination backup.
  /// The [metadata][google.longrunning.Operation.metadata] field type is
  /// [CopyBackupMetadata][google.spanner.admin.database.v1.CopyBackupMetadata].
  /// The [response][google.longrunning.Operation.response] field type is
  /// [Backup][google.spanner.admin.database.v1.Backup], if successful. Cancelling the returned operation will stop the
  /// copying and delete the backup.
  /// Concurrent CopyBackup requests can run on the same source backup.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.CopyBackupRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Backup] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.CopyBackupMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L254}
  /// [google.spanner.admin.database.v1.CopyBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L209}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Backup>> CopyBackup(
      google::spanner::admin::database::v1::CopyBackupRequest const& request,
      Options opts = {});

  // clang-format off
  ///
  /// Gets metadata on a pending or completed [Backup][google.spanner.admin.database.v1.Backup].
  ///
  /// @param name  Required. Name of the backup.
  ///  Values are of the form
  ///  `projects/<project>/instances/<instance>/backups/<backup>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.spanner.admin.database.v1.Backup])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.GetBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L305}
  ///
  // clang-format on
  StatusOr<google::spanner::admin::database::v1::Backup> GetBackup(
      std::string const& name, Options opts = {});

  // clang-format off
  ///
  /// Gets metadata on a pending or completed [Backup][google.spanner.admin.database.v1.Backup].
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.GetBackupRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.spanner.admin.database.v1.Backup])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.GetBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L305}
  ///
  // clang-format on
  StatusOr<google::spanner::admin::database::v1::Backup> GetBackup(
      google::spanner::admin::database::v1::GetBackupRequest const& request,
      Options opts = {});

  // clang-format off
  ///
  /// Updates a pending or completed [Backup][google.spanner.admin.database.v1.Backup].
  ///
  /// @param backup  Required. The backup to update. `backup.name`, and the fields to be updated
  ///  as specified by `update_mask` are required. Other fields are ignored.
  ///  Update is only supported for the following fields:
  ///   * `backup.expire_time`.
  /// @param update_mask  Required. A mask specifying which fields (e.g. `expire_time`) in the
  ///  Backup resource should be updated. This mask is relative to the Backup
  ///  resource, not to the request message. The field mask must always be
  ///  specified; this prevents any future fields from being erased accidentally
  ///  by clients that do not know about them.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.spanner.admin.database.v1.Backup])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.UpdateBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L289}
  ///
  // clang-format on
  StatusOr<google::spanner::admin::database::v1::Backup> UpdateBackup(
      google::spanner::admin::database::v1::Backup const& backup,
      google::protobuf::FieldMask const& update_mask, Options opts = {});

  // clang-format off
  ///
  /// Updates a pending or completed [Backup][google.spanner.admin.database.v1.Backup].
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.UpdateBackupRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return the result of the RPC. The response message type
  ///     ([google.spanner.admin.database.v1.Backup])
  ///     is mapped to a C++ class using the [Protobuf mapping rules].
  ///     If the request fails, the [`StatusOr`] contains the error details.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.UpdateBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L289}
  ///
  // clang-format on
  StatusOr<google::spanner::admin::database::v1::Backup> UpdateBackup(
      google::spanner::admin::database::v1::UpdateBackupRequest const& request,
      Options opts = {});

  // clang-format off
  ///
  /// Deletes a pending or completed [Backup][google.spanner.admin.database.v1.Backup].
  ///
  /// @param name  Required. Name of the backup to delete.
  ///  Values are of the form
  ///  `projects/<project>/instances/<instance>/backups/<backup>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [`Status`] object. If the request failed, the
  ///     status contains the details of the failure.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.DeleteBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L318}
  ///
  // clang-format on
  Status DeleteBackup(std::string const& name, Options opts = {});

  // clang-format off
  ///
  /// Deletes a pending or completed [Backup][google.spanner.admin.database.v1.Backup].
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.DeleteBackupRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [`Status`] object. If the request failed, the
  ///     status contains the details of the failure.
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.DeleteBackupRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L318}
  ///
  // clang-format on
  Status DeleteBackup(
      google::spanner::admin::database::v1::DeleteBackupRequest const& request,
      Options opts = {});

  // clang-format off
  ///
  /// Lists completed and pending backups.
  /// Backups returned are ordered by `create_time` in descending order,
  /// starting from the most recent `create_time`.
  ///
  /// @param parent  Required. The instance to list backups from.  Values are of the
  ///  form `projects/<project>/instances/<instance>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.spanner.admin.database.v1.Backup], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.ListBackupsRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L331}
  ///
  // clang-format on
  StreamRange<google::spanner::admin::database::v1::Backup> ListBackups(
      std::string const& parent, Options opts = {});

  // clang-format off
  ///
  /// Lists completed and pending backups.
  /// Backups returned are ordered by `create_time` in descending order,
  /// starting from the most recent `create_time`.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.ListBackupsRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.spanner.admin.database.v1.Backup], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.Backup]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L35}
  /// [google.spanner.admin.database.v1.ListBackupsRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L331}
  ///
  // clang-format on
  StreamRange<google::spanner::admin::database::v1::Backup> ListBackups(
      google::spanner::admin::database::v1::ListBackupsRequest request,
      Options opts = {});

  // clang-format off
  ///
  /// Create a new database by restoring from a completed backup. The new
  /// database must be in the same project and in an instance with the same
  /// instance configuration as the instance containing
  /// the backup. The returned database [long-running
  /// operation][google.longrunning.Operation] has a name of the format
  /// `projects/<project>/instances/<instance>/databases/<database>/operations/<operation_id>`,
  /// and can be used to track the progress of the operation, and to cancel it.
  /// The [metadata][google.longrunning.Operation.metadata] field type is
  /// [RestoreDatabaseMetadata][google.spanner.admin.database.v1.RestoreDatabaseMetadata].
  /// The [response][google.longrunning.Operation.response] type
  /// is [Database][google.spanner.admin.database.v1.Database], if
  /// successful. Cancelling the returned operation will stop the restore and
  /// delete the database.
  /// There can be only one database being restored into an instance at a time.
  /// Once the restore operation completes, a new restore operation can be
  /// initiated, without waiting for the optimize operation associated with the
  /// first restore to complete.
  ///
  /// @param parent  Required. The name of the instance in which to create the
  ///  restored database. This instance must be in the same project and
  ///  have the same instance configuration as the instance containing
  ///  the source backup. Values are of the form
  ///  `projects/<project>/instances/<instance>`.
  /// @param database_id  Required. The id of the database to create and restore to. This
  ///  database must not already exist. The `database_id` appended to
  ///  `parent` forms the full database name of the form
  ///  `projects/<project>/instances/<instance>/databases/<database_id>`.
  /// @param backup  Name of the backup from which to restore.  Values are of the form
  ///  `projects/<project>/instances/<instance>/backups/<backup>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Database] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  /// [google.spanner.admin.database.v1.RestoreDatabaseMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L902}
  /// [google.spanner.admin.database.v1.RestoreDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L828}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Database>>
  RestoreDatabase(std::string const& parent, std::string const& database_id,
                  std::string const& backup, Options opts = {});

  // clang-format off
  ///
  /// Create a new database by restoring from a completed backup. The new
  /// database must be in the same project and in an instance with the same
  /// instance configuration as the instance containing
  /// the backup. The returned database [long-running
  /// operation][google.longrunning.Operation] has a name of the format
  /// `projects/<project>/instances/<instance>/databases/<database>/operations/<operation_id>`,
  /// and can be used to track the progress of the operation, and to cancel it.
  /// The [metadata][google.longrunning.Operation.metadata] field type is
  /// [RestoreDatabaseMetadata][google.spanner.admin.database.v1.RestoreDatabaseMetadata].
  /// The [response][google.longrunning.Operation.response] type
  /// is [Database][google.spanner.admin.database.v1.Database], if
  /// successful. Cancelling the returned operation will stop the restore and
  /// delete the database.
  /// There can be only one database being restored into an instance at a time.
  /// Once the restore operation completes, a new restore operation can be
  /// initiated, without waiting for the optimize operation associated with the
  /// first restore to complete.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.RestoreDatabaseRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return A [`future`] that becomes satisfied when the LRO
  ///     ([Long Running Operation]) completes or the polling policy in effect
  ///     for this call is exhausted. The future is satisfied with an error if
  ///     the LRO completes with an error or the polling policy is exhausted.
  ///     In this case the [`StatusOr`] returned by the future contains the
  ///     error. If the LRO completes successfully the value of the future
  ///     contains the LRO's result. For this RPC the result is a
  ///     [google.spanner.admin.database.v1.Database] proto message.
  ///     The C++ class representing this message is created by Protobuf, using
  ///     the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.longrunning.Operation.response]: @googleapis_reference_link{google/longrunning/operations.proto#L160}
  /// [google.spanner.admin.database.v1.Database]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L415}
  /// [google.spanner.admin.database.v1.RestoreDatabaseMetadata]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L902}
  /// [google.spanner.admin.database.v1.RestoreDatabaseRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L828}
  ///
  // clang-format on
  future<StatusOr<google::spanner::admin::database::v1::Database>>
  RestoreDatabase(
      google::spanner::admin::database::v1::RestoreDatabaseRequest const&
          request,
      Options opts = {});

  // clang-format off
  ///
  /// Lists database [longrunning-operations][google.longrunning.Operation].
  /// A database operation has a name of the form
  /// `projects/<project>/instances/<instance>/databases/<database>/operations/<operation>`.
  /// The long-running operation
  /// [metadata][google.longrunning.Operation.metadata] field type
  /// `metadata.type_url` describes the type of the metadata. Operations returned
  /// include those that have completed/failed/canceled within the last 7 days,
  /// and pending operations.
  ///
  /// @param parent  Required. The instance of the database operations.
  ///  Values are of the form `projects/<project>/instances/<instance>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.longrunning.Operation], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.spanner.admin.database.v1.ListDatabaseOperationsRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L745}
  ///
  // clang-format on
  StreamRange<google::longrunning::Operation> ListDatabaseOperations(
      std::string const& parent, Options opts = {});

  // clang-format off
  ///
  /// Lists database [longrunning-operations][google.longrunning.Operation].
  /// A database operation has a name of the form
  /// `projects/<project>/instances/<instance>/databases/<database>/operations/<operation>`.
  /// The long-running operation
  /// [metadata][google.longrunning.Operation.metadata] field type
  /// `metadata.type_url` describes the type of the metadata. Operations returned
  /// include those that have completed/failed/canceled within the last 7 days,
  /// and pending operations.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.ListDatabaseOperationsRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.longrunning.Operation], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.spanner.admin.database.v1.ListDatabaseOperationsRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L745}
  ///
  // clang-format on
  StreamRange<google::longrunning::Operation> ListDatabaseOperations(
      google::spanner::admin::database::v1::ListDatabaseOperationsRequest
          request,
      Options opts = {});

  // clang-format off
  ///
  /// Lists the backup [long-running operations][google.longrunning.Operation] in
  /// the given instance. A backup operation has a name of the form
  /// `projects/<project>/instances/<instance>/backups/<backup>/operations/<operation>`.
  /// The long-running operation
  /// [metadata][google.longrunning.Operation.metadata] field type
  /// `metadata.type_url` describes the type of the metadata. Operations returned
  /// include those that have completed/failed/canceled within the last 7 days,
  /// and pending operations. Operations returned are ordered by
  /// `operation.metadata.value.progress.start_time` in descending order starting
  /// from the most recently started operation.
  ///
  /// @param parent  Required. The instance of the backup operations. Values are of
  ///  the form `projects/<project>/instances/<instance>`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.longrunning.Operation], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.spanner.admin.database.v1.ListBackupOperationsRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L403}
  ///
  // clang-format on
  StreamRange<google::longrunning::Operation> ListBackupOperations(
      std::string const& parent, Options opts = {});

  // clang-format off
  ///
  /// Lists the backup [long-running operations][google.longrunning.Operation] in
  /// the given instance. A backup operation has a name of the form
  /// `projects/<project>/instances/<instance>/backups/<backup>/operations/<operation>`.
  /// The long-running operation
  /// [metadata][google.longrunning.Operation.metadata] field type
  /// `metadata.type_url` describes the type of the metadata. Operations returned
  /// include those that have completed/failed/canceled within the last 7 days,
  /// and pending operations. Operations returned are ordered by
  /// `operation.metadata.value.progress.start_time` in descending order starting
  /// from the most recently started operation.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.ListBackupOperationsRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.longrunning.Operation], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.longrunning.Operation]: @googleapis_reference_link{google/longrunning/operations.proto#L128}
  /// [google.longrunning.Operation.metadata]: @googleapis_reference_link{google/longrunning/operations.proto#L138}
  /// [google.spanner.admin.database.v1.ListBackupOperationsRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/backup.proto#L403}
  ///
  // clang-format on
  StreamRange<google::longrunning::Operation> ListBackupOperations(
      google::spanner::admin::database::v1::ListBackupOperationsRequest request,
      Options opts = {});

  // clang-format off
  ///
  /// Lists Cloud Spanner database roles.
  ///
  /// @param parent  Required. The database whose roles should be listed.
  ///  Values are of the form
  ///  `projects/<project>/instances/<instance>/databases/<database>/databaseRoles`.
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.spanner.admin.database.v1.DatabaseRole], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.DatabaseRole]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L974}
  /// [google.spanner.admin.database.v1.ListDatabaseRolesRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L989}
  ///
  // clang-format on
  StreamRange<google::spanner::admin::database::v1::DatabaseRole>
  ListDatabaseRoles(std::string const& parent, Options opts = {});

  // clang-format off
  ///
  /// Lists Cloud Spanner database roles.
  ///
  /// @param request Unary RPCs, such as the one wrapped by this
  ///     function, receive a single `request` proto message which includes all
  ///     the inputs for the RPC. In this case, the proto message is a
  ///     [google.spanner.admin.database.v1.ListDatabaseRolesRequest].
  ///     Proto messages are converted to C++ classes by Protobuf, using the
  ///     [Protobuf mapping rules].
  /// @param opts Optional. Override the class-level options, such as retry and
  ///     backoff policies.
  /// @return a [StreamRange](@ref google::cloud::StreamRange)
  ///     to iterate of the results. See the documentation of this type for
  ///     details. In brief, this class has `begin()` and `end()` member
  ///     functions returning a iterator class meeting the
  ///     [input iterator requirements]. The value type for this iterator is a
  ///     [`StatusOr`] as the iteration may fail even after some values are
  ///     retrieved successfully, for example, if there is a network disconnect.
  ///     An empty set of results does not indicate an error, it indicates
  ///     that there are no resources meeting the request criteria.
  ///     On a successful iteration the `StatusOr<T>` contains elements of type
  ///     [google.spanner.admin.database.v1.DatabaseRole], or rather,
  ///     the C++ class generated by Protobuf from that type. Please consult the
  ///     Protobuf documentation for details on the [Protobuf mapping rules].
  ///
  /// [Protobuf mapping rules]: https://protobuf.dev/reference/cpp/cpp-generated/
  /// [input iterator requirements]: https://en.cppreference.com/w/cpp/named_req/InputIterator
  /// [Long Running Operation]: https://google.aip.dev/151
  /// [`std::string`]: https://en.cppreference.com/w/cpp/string/basic_string
  /// [`future`]: @ref google::cloud::future
  /// [`StatusOr`]: @ref google::cloud::StatusOr
  /// [`Status`]: @ref google::cloud::Status
  /// [google.spanner.admin.database.v1.DatabaseRole]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L974}
  /// [google.spanner.admin.database.v1.ListDatabaseRolesRequest]: @googleapis_reference_link{google/spanner/admin/database/v1/spanner_database_admin.proto#L989}
  ///
  // clang-format on
  StreamRange<google::spanner::admin::database::v1::DatabaseRole>
  ListDatabaseRoles(
      google::spanner::admin::database::v1::ListDatabaseRolesRequest request,
      Options opts = {});

 private:
  std::shared_ptr<DatabaseAdminConnection> connection_;
  Options options_;
};

GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_END
namespace gcpcxxV1 = GOOGLE_CLOUD_CPP_NS;  // NOLINT(misc-unused-alias-decls)
}  // namespace spanner_admin
}  // namespace cloud
}  // namespace google

#endif  // GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_SPANNER_ADMIN_DATABASE_ADMIN_CLIENT_H