# -*- coding: utf-8 -*-
#
# Copyright 2019 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.

"""Accesses the google.spanner.admin.instance.v1 InstanceAdmin API."""

import functools
import pkg_resources
import warnings

from google.oauth2 import service_account
import google.api_core.client_options
import google.api_core.gapic_v1.client_info
import google.api_core.gapic_v1.config
import google.api_core.gapic_v1.method
import google.api_core.gapic_v1.routing_header
import google.api_core.grpc_helpers
import google.api_core.operation
import google.api_core.operations_v1
import google.api_core.page_iterator
import google.api_core.path_template
import grpc

from google.cloud.spanner_admin_instance_v1.gapic import enums
from google.cloud.spanner_admin_instance_v1.gapic import instance_admin_client_config
from google.cloud.spanner_admin_instance_v1.gapic.transports import (
    instance_admin_grpc_transport,
)
from google.cloud.spanner_admin_instance_v1.proto import spanner_instance_admin_pb2
from google.cloud.spanner_admin_instance_v1.proto import spanner_instance_admin_pb2_grpc
from google.iam.v1 import iam_policy_pb2
from google.iam.v1 import options_pb2
from google.iam.v1 import policy_pb2
from google.longrunning import operations_pb2
from google.protobuf import empty_pb2
from google.protobuf import field_mask_pb2


_GAPIC_LIBRARY_VERSION = pkg_resources.get_distribution("google-cloud-spanner").version


class InstanceAdminClient(object):
    """
    Cloud Spanner Instance Admin API

    The Cloud Spanner Instance Admin API can be used to create, delete,
    modify and list instances. Instances are dedicated Cloud Spanner serving
    and storage resources to be used by Cloud Spanner databases.

    Each instance has a "configuration", which dictates where the
    serving resources for the Cloud Spanner instance are located (e.g.,
    US-central, Europe). Configurations are created by Google based on
    resource availability.

    Cloud Spanner billing is based on the instances that exist and their
    sizes. After an instance exists, there are no additional
    per-database or per-operation charges for use of the instance
    (though there may be additional network bandwidth charges).
    Instances offer isolation: problems with databases in one instance
    will not affect other instances. However, within an instance
    databases can affect each other. For example, if one database in an
    instance receives a lot of requests and consumes most of the
    instance resources, fewer resources are available for other
    databases in that instance, and their performance may suffer.
    """

    SERVICE_ADDRESS = "spanner.googleapis.com:443"
    """The default address of the service."""

    # The name of the interface for this client. This is the key used to
    # find the method configuration in the client_config dictionary.
    _INTERFACE_NAME = "google.spanner.admin.instance.v1.InstanceAdmin"

    @classmethod
    def from_service_account_file(cls, filename, *args, **kwargs):
        """Creates an instance of this client using the provided credentials
        file.

        Args:
            filename (str): The path to the service account private key json
                file.
            args: Additional arguments to pass to the constructor.
            kwargs: Additional arguments to pass to the constructor.

        Returns:
            InstanceAdminClient: The constructed client.
        """
        credentials = service_account.Credentials.from_service_account_file(filename)
        kwargs["credentials"] = credentials
        return cls(*args, **kwargs)

    from_service_account_json = from_service_account_file

    @classmethod
    def instance_path(cls, project, instance):
        """Return a fully-qualified instance string."""
        return google.api_core.path_template.expand(
            "projects/{project}/instances/{instance}",
            project=project,
            instance=instance,
        )

    @classmethod
    def instance_config_path(cls, project, instance_config):
        """Return a fully-qualified instance_config string."""
        return google.api_core.path_template.expand(
            "projects/{project}/instanceConfigs/{instance_config}",
            project=project,
            instance_config=instance_config,
        )

    @classmethod
    def project_path(cls, project):
        """Return a fully-qualified project string."""
        return google.api_core.path_template.expand(
            "projects/{project}", project=project
        )

    def __init__(
        self,
        transport=None,
        channel=None,
        credentials=None,
        client_config=None,
        client_info=None,
        client_options=None,
    ):
        """Constructor.

        Args:
            transport (Union[~.InstanceAdminGrpcTransport,
                    Callable[[~.Credentials, type], ~.InstanceAdminGrpcTransport]): A transport
                instance, responsible for actually making the API calls.
                The default transport uses the gRPC protocol.
                This argument may also be a callable which returns a
                transport instance. Callables will be sent the credentials
                as the first argument and the default transport class as
                the second argument.
            channel (grpc.Channel): DEPRECATED. A ``Channel`` instance
                through which to make calls. This argument is mutually exclusive
                with ``credentials``; providing both will raise an exception.
            credentials (google.auth.credentials.Credentials): The
                authorization credentials to attach to requests. These
                credentials identify this application to the service. If none
                are specified, the client will attempt to ascertain the
                credentials from the environment.
                This argument is mutually exclusive with providing a
                transport instance to ``transport``; doing so will raise
                an exception.
            client_config (dict): DEPRECATED. A dictionary of call options for
                each method. If not specified, the default configuration is used.
            client_info (google.api_core.gapic_v1.client_info.ClientInfo):
                The client info used to send a user-agent string along with
                API requests. If ``None``, then default info will be used.
                Generally, you only need to set this if you're developing
                your own client library.
            client_options (Union[dict, google.api_core.client_options.ClientOptions]):
                Client options used to set user options on the client. API Endpoint
                should be set through client_options.
        """
        # Raise deprecation warnings for things we want to go away.
        if client_config is not None:
            warnings.warn(
                "The `client_config` argument is deprecated.",
                PendingDeprecationWarning,
                stacklevel=2,
            )
        else:
            client_config = instance_admin_client_config.config

        if channel:
            warnings.warn(
                "The `channel` argument is deprecated; use " "`transport` instead.",
                PendingDeprecationWarning,
                stacklevel=2,
            )

        api_endpoint = self.SERVICE_ADDRESS
        if client_options:
            if type(client_options) == dict:
                client_options = google.api_core.client_options.from_dict(
                    client_options
                )
            if client_options.api_endpoint:
                api_endpoint = client_options.api_endpoint

        # Instantiate the transport.
        # The transport is responsible for handling serialization and
        # deserialization and actually sending data to the service.
        if transport:
            if callable(transport):
                self.transport = transport(
                    credentials=credentials,
                    default_class=instance_admin_grpc_transport.InstanceAdminGrpcTransport,
                    address=api_endpoint,
                )
            else:
                if credentials:
                    raise ValueError(
                        "Received both a transport instance and "
                        "credentials; these are mutually exclusive."
                    )
                self.transport = transport
        else:
            self.transport = instance_admin_grpc_transport.InstanceAdminGrpcTransport(
                address=api_endpoint, channel=channel, credentials=credentials
            )

        if client_info is None:
            client_info = google.api_core.gapic_v1.client_info.ClientInfo(
                gapic_version=_GAPIC_LIBRARY_VERSION
            )
        else:
            client_info.gapic_version = _GAPIC_LIBRARY_VERSION
        self._client_info = client_info

        # Parse out the default settings for retry and timeout for each RPC
        # from the client configuration.
        # (Ordinarily, these are the defaults specified in the `*_config.py`
        # file next to this one.)
        self._method_configs = google.api_core.gapic_v1.config.parse_method_configs(
            client_config["interfaces"][self._INTERFACE_NAME]
        )

        # Save a dictionary of cached API call functions.
        # These are the actual callables which invoke the proper
        # transport methods, wrapped with `wrap_method` to add retry,
        # timeout, and the like.
        self._inner_api_calls = {}

    # Service calls
    def list_instance_configs(
        self,
        parent,
        page_size=None,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Lists the supported instance configurations for a given project.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> parent = client.project_path('[PROJECT]')
            >>>
            >>> # Iterate over all results
            >>> for element in client.list_instance_configs(parent):
            ...     # process element
            ...     pass
            >>>
            >>>
            >>> # Alternatively:
            >>>
            >>> # Iterate over results one page at a time
            >>> for page in client.list_instance_configs(parent).pages:
            ...     for element in page:
            ...         # process element
            ...         pass

        Args:
            parent (str): Required. The name of the project for which a list of supported instance
                configurations is requested. Values are of the form
                ``projects/<project>``.
            page_size (int): The maximum number of resources contained in the
                underlying API response. If page streaming is performed per-
                resource, this parameter does not affect the return value. If page
                streaming is performed per-page, this determines the maximum number
                of resources in a page.
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.api_core.page_iterator.PageIterator` instance.
            An iterable of :class:`~google.cloud.spanner_admin_instance_v1.types.InstanceConfig` instances.
            You can also iterate over the pages of the response
            using its `pages` property.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "list_instance_configs" not in self._inner_api_calls:
            self._inner_api_calls[
                "list_instance_configs"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.list_instance_configs,
                default_retry=self._method_configs["ListInstanceConfigs"].retry,
                default_timeout=self._method_configs["ListInstanceConfigs"].timeout,
                client_info=self._client_info,
            )

        request = spanner_instance_admin_pb2.ListInstanceConfigsRequest(
            parent=parent, page_size=page_size
        )
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("parent", parent)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        iterator = google.api_core.page_iterator.GRPCIterator(
            client=None,
            method=functools.partial(
                self._inner_api_calls["list_instance_configs"],
                retry=retry,
                timeout=timeout,
                metadata=metadata,
            ),
            request=request,
            items_field="instance_configs",
            request_token_field="page_token",
            response_token_field="next_page_token",
        )
        return iterator

    def get_instance_config(
        self,
        name,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Gets information about a particular instance configuration.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> name = client.instance_config_path('[PROJECT]', '[INSTANCE_CONFIG]')
            >>>
            >>> response = client.get_instance_config(name)

        Args:
            name (str): Required. The name of the requested instance configuration. Values are
                of the form ``projects/<project>/instanceConfigs/<config>``.
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.cloud.spanner_admin_instance_v1.types.InstanceConfig` instance.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "get_instance_config" not in self._inner_api_calls:
            self._inner_api_calls[
                "get_instance_config"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.get_instance_config,
                default_retry=self._method_configs["GetInstanceConfig"].retry,
                default_timeout=self._method_configs["GetInstanceConfig"].timeout,
                client_info=self._client_info,
            )

        request = spanner_instance_admin_pb2.GetInstanceConfigRequest(name=name)
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("name", name)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        return self._inner_api_calls["get_instance_config"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )

    def list_instances(
        self,
        parent,
        page_size=None,
        filter_=None,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Lists all instances in the given project.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> parent = client.project_path('[PROJECT]')
            >>>
            >>> # Iterate over all results
            >>> for element in client.list_instances(parent):
            ...     # process element
            ...     pass
            >>>
            >>>
            >>> # Alternatively:
            >>>
            >>> # Iterate over results one page at a time
            >>> for page in client.list_instances(parent).pages:
            ...     for element in page:
            ...         # process element
            ...         pass

        Args:
            parent (str): Required. The name of the project for which a list of instances is
                requested. Values are of the form ``projects/<project>``.
            page_size (int): The maximum number of resources contained in the
                underlying API response. If page streaming is performed per-
                resource, this parameter does not affect the return value. If page
                streaming is performed per-page, this determines the maximum number
                of resources in a page.
            filter_ (str): An expression for filtering the results of the request. Filter rules are
                case insensitive. The fields eligible for filtering are:

                -  ``name``
                -  ``display_name``
                -  ``labels.key`` where key is the name of a label

                Some examples of using filters are:

                -  ``name:*`` --> The instance has a name.
                -  ``name:Howl`` --> The instance's name contains the string "howl".
                -  ``name:HOWL`` --> Equivalent to above.
                -  ``NAME:howl`` --> Equivalent to above.
                -  ``labels.env:*`` --> The instance has the label "env".
                -  ``labels.env:dev`` --> The instance has the label "env" and the value
                   of the label contains the string "dev".
                -  ``name:howl labels.env:dev`` --> The instance's name contains "howl"
                   and it has the label "env" with its value containing "dev".
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.api_core.page_iterator.PageIterator` instance.
            An iterable of :class:`~google.cloud.spanner_admin_instance_v1.types.Instance` instances.
            You can also iterate over the pages of the response
            using its `pages` property.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "list_instances" not in self._inner_api_calls:
            self._inner_api_calls[
                "list_instances"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.list_instances,
                default_retry=self._method_configs["ListInstances"].retry,
                default_timeout=self._method_configs["ListInstances"].timeout,
                client_info=self._client_info,
            )

        request = spanner_instance_admin_pb2.ListInstancesRequest(
            parent=parent, page_size=page_size, filter=filter_
        )
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("parent", parent)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        iterator = google.api_core.page_iterator.GRPCIterator(
            client=None,
            method=functools.partial(
                self._inner_api_calls["list_instances"],
                retry=retry,
                timeout=timeout,
                metadata=metadata,
            ),
            request=request,
            items_field="instances",
            request_token_field="page_token",
            response_token_field="next_page_token",
        )
        return iterator

    def get_instance(
        self,
        name,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Gets information about a particular instance.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> name = client.instance_path('[PROJECT]', '[INSTANCE]')
            >>>
            >>> response = client.get_instance(name)

        Args:
            name (str): Required. The name of the requested instance. Values are of the form
                ``projects/<project>/instances/<instance>``.
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.cloud.spanner_admin_instance_v1.types.Instance` instance.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "get_instance" not in self._inner_api_calls:
            self._inner_api_calls[
                "get_instance"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.get_instance,
                default_retry=self._method_configs["GetInstance"].retry,
                default_timeout=self._method_configs["GetInstance"].timeout,
                client_info=self._client_info,
            )

        request = spanner_instance_admin_pb2.GetInstanceRequest(name=name)
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("name", name)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        return self._inner_api_calls["get_instance"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )

    def create_instance(
        self,
        parent,
        instance_id,
        instance,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Creates an instance and begins preparing it to begin serving. The
        returned ``long-running operation`` can be used to track the progress of
        preparing the new instance. The instance name is assigned by the caller.
        If the named instance already exists, ``CreateInstance`` returns
        ``ALREADY_EXISTS``.

        Immediately upon completion of this request:

        -  The instance is readable via the API, with all requested attributes
           but no allocated resources. Its state is ``CREATING``.

        Until completion of the returned operation:

        -  Cancelling the operation renders the instance immediately unreadable
           via the API.
        -  The instance can be deleted.
        -  All other attempts to modify the instance are rejected.

        Upon completion of the returned operation:

        -  Billing for all successfully-allocated resources begins (some types
           may have lower than the requested levels).
        -  Databases can be created in the instance.
        -  The instance's allocated resource levels are readable via the API.
        -  The instance's state becomes ``READY``.

        The returned ``long-running operation`` will have a name of the format
        ``<instance_name>/operations/<operation_id>`` and can be used to track
        creation of the instance. The ``metadata`` field type is
        ``CreateInstanceMetadata``. The ``response`` field type is ``Instance``,
        if successful.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> parent = client.project_path('[PROJECT]')
            >>>
            >>> # TODO: Initialize `instance_id`:
            >>> instance_id = ''
            >>>
            >>> # TODO: Initialize `instance`:
            >>> instance = {}
            >>>
            >>> response = client.create_instance(parent, instance_id, instance)
            >>>
            >>> def callback(operation_future):
            ...     # Handle result.
            ...     result = operation_future.result()
            >>>
            >>> response.add_done_callback(callback)
            >>>
            >>> # Handle metadata.
            >>> metadata = response.metadata()

        Args:
            parent (str): Required. The name of the project in which to create the instance.
                Values are of the form ``projects/<project>``.
            instance_id (str): Required. The ID of the instance to create. Valid identifiers are of the
                form ``[a-z][-a-z0-9]*[a-z0-9]`` and must be between 6 and 30 characters
                in length.
            instance (Union[dict, ~google.cloud.spanner_admin_instance_v1.types.Instance]): Required. The instance to create. The name may be omitted, but if
                specified must be ``<parent>/instances/<instance_id>``.

                If a dict is provided, it must be of the same form as the protobuf
                message :class:`~google.cloud.spanner_admin_instance_v1.types.Instance`
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.cloud.spanner_admin_instance_v1.types._OperationFuture` instance.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "create_instance" not in self._inner_api_calls:
            self._inner_api_calls[
                "create_instance"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.create_instance,
                default_retry=self._method_configs["CreateInstance"].retry,
                default_timeout=self._method_configs["CreateInstance"].timeout,
                client_info=self._client_info,
            )

        request = spanner_instance_admin_pb2.CreateInstanceRequest(
            parent=parent, instance_id=instance_id, instance=instance
        )
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("parent", parent)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        operation = self._inner_api_calls["create_instance"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )
        return google.api_core.operation.from_gapic(
            operation,
            self.transport._operations_client,
            spanner_instance_admin_pb2.Instance,
            metadata_type=spanner_instance_admin_pb2.CreateInstanceMetadata,
        )

    def update_instance(
        self,
        instance,
        field_mask,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Updates an instance, and begins allocating or releasing resources as
        requested. The returned ``long-running operation`` can be used to track
        the progress of updating the instance. If the named instance does not
        exist, returns ``NOT_FOUND``.

        Immediately upon completion of this request:

        -  For resource types for which a decrease in the instance's allocation
           has been requested, billing is based on the newly-requested level.

        Until completion of the returned operation:

        -  Cancelling the operation sets its metadata's ``cancel_time``, and
           begins restoring resources to their pre-request values. The operation
           is guaranteed to succeed at undoing all resource changes, after which
           point it terminates with a ``CANCELLED`` status.
        -  All other attempts to modify the instance are rejected.
        -  Reading the instance via the API continues to give the pre-request
           resource levels.

        Upon completion of the returned operation:

        -  Billing begins for all successfully-allocated resources (some types
           may have lower than the requested levels).
        -  All newly-reserved resources are available for serving the instance's
           tables.
        -  The instance's new resource levels are readable via the API.

        The returned ``long-running operation`` will have a name of the format
        ``<instance_name>/operations/<operation_id>`` and can be used to track
        the instance modification. The ``metadata`` field type is
        ``UpdateInstanceMetadata``. The ``response`` field type is ``Instance``,
        if successful.

        Authorization requires ``spanner.instances.update`` permission on
        resource ``name``.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> # TODO: Initialize `instance`:
            >>> instance = {}
            >>>
            >>> # TODO: Initialize `field_mask`:
            >>> field_mask = {}
            >>>
            >>> response = client.update_instance(instance, field_mask)
            >>>
            >>> def callback(operation_future):
            ...     # Handle result.
            ...     result = operation_future.result()
            >>>
            >>> response.add_done_callback(callback)
            >>>
            >>> # Handle metadata.
            >>> metadata = response.metadata()

        Args:
            instance (Union[dict, ~google.cloud.spanner_admin_instance_v1.types.Instance]): Required. The instance to update, which must always include the instance
                name. Otherwise, only fields mentioned in
                [][google.spanner.admin.instance.v1.UpdateInstanceRequest.field\_mask]
                need be included.

                If a dict is provided, it must be of the same form as the protobuf
                message :class:`~google.cloud.spanner_admin_instance_v1.types.Instance`
            field_mask (Union[dict, ~google.cloud.spanner_admin_instance_v1.types.FieldMask]): Required. A mask specifying which fields in
                [][google.spanner.admin.instance.v1.UpdateInstanceRequest.instance]
                should be updated. The field mask must always be specified; this
                prevents any future fields in
                [][google.spanner.admin.instance.v1.Instance] from being erased
                accidentally by clients that do not know about them.

                If a dict is provided, it must be of the same form as the protobuf
                message :class:`~google.cloud.spanner_admin_instance_v1.types.FieldMask`
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.cloud.spanner_admin_instance_v1.types._OperationFuture` instance.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "update_instance" not in self._inner_api_calls:
            self._inner_api_calls[
                "update_instance"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.update_instance,
                default_retry=self._method_configs["UpdateInstance"].retry,
                default_timeout=self._method_configs["UpdateInstance"].timeout,
                client_info=self._client_info,
            )

        request = spanner_instance_admin_pb2.UpdateInstanceRequest(
            instance=instance, field_mask=field_mask
        )
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("instance.name", instance.name)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        operation = self._inner_api_calls["update_instance"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )
        return google.api_core.operation.from_gapic(
            operation,
            self.transport._operations_client,
            spanner_instance_admin_pb2.Instance,
            metadata_type=spanner_instance_admin_pb2.UpdateInstanceMetadata,
        )

    def delete_instance(
        self,
        name,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Deletes an instance.

        Immediately upon completion of the request:

        -  Billing ceases for all of the instance's reserved resources.

        Soon afterward:

        -  The instance and *all of its databases* immediately and irrevocably
           disappear from the API. All data in the databases is permanently
           deleted.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> name = client.instance_path('[PROJECT]', '[INSTANCE]')
            >>>
            >>> client.delete_instance(name)

        Args:
            name (str): Required. The name of the instance to be deleted. Values are of the form
                ``projects/<project>/instances/<instance>``
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "delete_instance" not in self._inner_api_calls:
            self._inner_api_calls[
                "delete_instance"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.delete_instance,
                default_retry=self._method_configs["DeleteInstance"].retry,
                default_timeout=self._method_configs["DeleteInstance"].timeout,
                client_info=self._client_info,
            )

        request = spanner_instance_admin_pb2.DeleteInstanceRequest(name=name)
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("name", name)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        self._inner_api_calls["delete_instance"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )

    def set_iam_policy(
        self,
        resource,
        policy,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Sets the access control policy on an instance resource. Replaces any
        existing policy.

        Authorization requires ``spanner.instances.setIamPolicy`` on
        ``resource``.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> resource = client.instance_path('[PROJECT]', '[INSTANCE]')
            >>>
            >>> # TODO: Initialize `policy`:
            >>> policy = {}
            >>>
            >>> response = client.set_iam_policy(resource, policy)

        Args:
            resource (str): REQUIRED: The resource for which the policy is being specified.
                See the operation documentation for the appropriate value for this field.
            policy (Union[dict, ~google.cloud.spanner_admin_instance_v1.types.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.

                If a dict is provided, it must be of the same form as the protobuf
                message :class:`~google.cloud.spanner_admin_instance_v1.types.Policy`
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.cloud.spanner_admin_instance_v1.types.Policy` instance.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "set_iam_policy" not in self._inner_api_calls:
            self._inner_api_calls[
                "set_iam_policy"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.set_iam_policy,
                default_retry=self._method_configs["SetIamPolicy"].retry,
                default_timeout=self._method_configs["SetIamPolicy"].timeout,
                client_info=self._client_info,
            )

        request = iam_policy_pb2.SetIamPolicyRequest(resource=resource, policy=policy)
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("resource", resource)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        return self._inner_api_calls["set_iam_policy"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )

    def get_iam_policy(
        self,
        resource,
        options_=None,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Gets the access control policy for an instance resource. Returns an
        empty policy if an instance exists but does not have a policy set.

        Authorization requires ``spanner.instances.getIamPolicy`` on
        ``resource``.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> resource = client.instance_path('[PROJECT]', '[INSTANCE]')
            >>>
            >>> response = client.get_iam_policy(resource)

        Args:
            resource (str): REQUIRED: The resource for which the policy is being requested.
                See the operation documentation for the appropriate value for this field.
            options_ (Union[dict, ~google.cloud.spanner_admin_instance_v1.types.GetPolicyOptions]): OPTIONAL: A ``GetPolicyOptions`` object for specifying options to
                ``GetIamPolicy``. This field is only used by Cloud IAM.

                If a dict is provided, it must be of the same form as the protobuf
                message :class:`~google.cloud.spanner_admin_instance_v1.types.GetPolicyOptions`
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.cloud.spanner_admin_instance_v1.types.Policy` instance.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "get_iam_policy" not in self._inner_api_calls:
            self._inner_api_calls[
                "get_iam_policy"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.get_iam_policy,
                default_retry=self._method_configs["GetIamPolicy"].retry,
                default_timeout=self._method_configs["GetIamPolicy"].timeout,
                client_info=self._client_info,
            )

        request = iam_policy_pb2.GetIamPolicyRequest(
            resource=resource, options=options_
        )
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("resource", resource)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        return self._inner_api_calls["get_iam_policy"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )

    def test_iam_permissions(
        self,
        resource,
        permissions,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Returns permissions that the caller has on the specified instance
        resource.

        Attempting this RPC on a non-existent Cloud Spanner instance resource
        will result in a NOT\_FOUND error if the user has
        ``spanner.instances.list`` permission on the containing Google Cloud
        Project. Otherwise returns an empty set of permissions.

        Example:
            >>> from google.cloud import spanner_admin_instance_v1
            >>>
            >>> client = spanner_admin_instance_v1.InstanceAdminClient()
            >>>
            >>> resource = client.instance_path('[PROJECT]', '[INSTANCE]')
            >>>
            >>> # TODO: Initialize `permissions`:
            >>> permissions = []
            >>>
            >>> response = client.test_iam_permissions(resource, permissions)

        Args:
            resource (str): REQUIRED: The resource for which the policy detail is being requested.
                See the operation documentation for the appropriate value for this field.
            permissions (list[str]): 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>`__.
            retry (Optional[google.api_core.retry.Retry]):  A retry object used
                to retry requests. If ``None`` is specified, requests will
                be retried using a default configuration.
            timeout (Optional[float]): The amount of time, in seconds, to wait
                for the request to complete. Note that if ``retry`` is
                specified, the timeout applies to each individual attempt.
            metadata (Optional[Sequence[Tuple[str, str]]]): Additional metadata
                that is provided to the method.

        Returns:
            A :class:`~google.cloud.spanner_admin_instance_v1.types.TestIamPermissionsResponse` instance.

        Raises:
            google.api_core.exceptions.GoogleAPICallError: If the request
                    failed for any reason.
            google.api_core.exceptions.RetryError: If the request failed due
                    to a retryable error and retry attempts failed.
            ValueError: If the parameters are invalid.
        """
        # Wrap the transport method to add retry and timeout logic.
        if "test_iam_permissions" not in self._inner_api_calls:
            self._inner_api_calls[
                "test_iam_permissions"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.test_iam_permissions,
                default_retry=self._method_configs["TestIamPermissions"].retry,
                default_timeout=self._method_configs["TestIamPermissions"].timeout,
                client_info=self._client_info,
            )

        request = iam_policy_pb2.TestIamPermissionsRequest(
            resource=resource, permissions=permissions
        )
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("resource", resource)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        return self._inner_api_calls["test_iam_permissions"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )
