logging_service_v2_client.py

# -*- coding: utf-8 -*-
#
# Copyright 2020 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.logging.v2 LoggingServiceV2 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.page_iterator
import google.api_core.path_template
import grpc

from google.api import monitored_resource_pb2
from google.cloud.logging_v2.gapic import enums
from google.cloud.logging_v2.gapic import logging_service_v2_client_config
from google.cloud.logging_v2.gapic.transports import logging_service_v2_grpc_transport
from google.cloud.logging_v2.proto import log_entry_pb2
from google.cloud.logging_v2.proto import logging_config_pb2
from google.cloud.logging_v2.proto import logging_config_pb2_grpc
from google.cloud.logging_v2.proto import logging_pb2
from google.cloud.logging_v2.proto import logging_pb2_grpc
from google.protobuf import empty_pb2
from google.protobuf import field_mask_pb2


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


class LoggingServiceV2Client(object):
    """Service for ingesting and querying logs."""

    SERVICE_ADDRESS = "logging.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.logging.v2.LoggingServiceV2"

    @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:
            LoggingServiceV2Client: 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 billing_path(cls, billing_account):
        """Return a fully-qualified billing string."""
        return google.api_core.path_template.expand(
            "billingAccounts/{billing_account}", billing_account=billing_account,
        )

    @classmethod
    def billing_log_path(cls, billing_account, log):
        """Return a fully-qualified billing_log string."""
        return google.api_core.path_template.expand(
            "billingAccounts/{billing_account}/logs/{log}",
            billing_account=billing_account,
            log=log,
        )

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

    @classmethod
    def folder_log_path(cls, folder, log):
        """Return a fully-qualified folder_log string."""
        return google.api_core.path_template.expand(
            "folders/{folder}/logs/{log}", folder=folder, log=log,
        )

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

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

    @classmethod
    def organization_log_path(cls, organization, log):
        """Return a fully-qualified organization_log string."""
        return google.api_core.path_template.expand(
            "organizations/{organization}/logs/{log}",
            organization=organization,
            log=log,
        )

    @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[~.LoggingServiceV2GrpcTransport,
                    Callable[[~.Credentials, type], ~.LoggingServiceV2GrpcTransport]): 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 = logging_service_v2_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=logging_service_v2_grpc_transport.LoggingServiceV2GrpcTransport,
                    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 = logging_service_v2_grpc_transport.LoggingServiceV2GrpcTransport(
                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 delete_log(
        self,
        log_name,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Deletes all the log entries in a log. The log reappears if it receives new
        entries. Log entries written shortly before the delete operation might not
        be deleted. Entries received after the delete operation with a timestamp
        before the operation will be deleted.

        Example:
            >>> from google.cloud import logging_v2
            >>>
            >>> client = logging_v2.LoggingServiceV2Client()
            >>>
            >>> log_name = client.log_path('[PROJECT]', '[LOG]')
            >>>
            >>> client.delete_log(log_name)

        Args:
            log_name (str): Required. The resource name of the log to delete:

                ::

                     "projects/[PROJECT_ID]/logs/[LOG_ID]"
                     "organizations/[ORGANIZATION_ID]/logs/[LOG_ID]"
                     "billingAccounts/[BILLING_ACCOUNT_ID]/logs/[LOG_ID]"
                     "folders/[FOLDER_ID]/logs/[LOG_ID]"

                ``[LOG_ID]`` must be URL-encoded. For example,
                ``"projects/my-project-id/logs/syslog"``,
                ``"organizations/1234567890/logs/cloudresourcemanager.googleapis.com%2Factivity"``.
                For more information about log names, see ``LogEntry``.
            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_log" not in self._inner_api_calls:
            self._inner_api_calls[
                "delete_log"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.delete_log,
                default_retry=self._method_configs["DeleteLog"].retry,
                default_timeout=self._method_configs["DeleteLog"].timeout,
                client_info=self._client_info,
            )

        request = logging_pb2.DeleteLogRequest(log_name=log_name,)
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("log_name", log_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_log"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )

    def write_log_entries(
        self,
        entries,
        log_name=None,
        resource=None,
        labels=None,
        partial_success=None,
        dry_run=None,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Writes log entries to Logging. This API method is the
        only way to send log entries to Logging. This method
        is used, directly or indirectly, by the Logging agent
        (fluentd) and all logging libraries configured to use Logging.
        A single request may contain log entries for a maximum of 1000
        different resources (projects, organizations, billing accounts or
        folders)

        Example:
            >>> from google.cloud import logging_v2
            >>>
            >>> client = logging_v2.LoggingServiceV2Client()
            >>>
            >>> # TODO: Initialize `entries`:
            >>> entries = []
            >>>
            >>> response = client.write_log_entries(entries)

        Args:
            entries (list[Union[dict, ~google.cloud.logging_v2.types.LogEntry]]): Required. The log entries to send to Logging. The order of log entries
                in this list does not matter. Values supplied in this method's
                ``log_name``, ``resource``, and ``labels`` fields are copied into those
                log entries in this list that do not include values for their
                corresponding fields. For more information, see the ``LogEntry`` type.

                If the ``timestamp`` or ``insert_id`` fields are missing in log entries,
                then this method supplies the current time or a unique identifier,
                respectively. The supplied values are chosen so that, among the log
                entries that did not supply their own values, the entries earlier in the
                list will sort before the entries later in the list. See the
                ``entries.list`` method.

                Log entries with timestamps that are more than the `logs retention
                period <https://cloud.google.com/logging/quota-policy>`__ in the past or
                more than 24 hours in the future will not be available when calling
                ``entries.list``. However, those log entries can still be `exported with
                LogSinks <https://cloud.google.com/logging/docs/api/tasks/exporting-logs>`__.

                To improve throughput and to avoid exceeding the `quota
                limit <https://cloud.google.com/logging/quota-policy>`__ for calls to
                ``entries.write``, you should try to include several log entries in this
                list, rather than calling this method for each individual log entry.

                If a dict is provided, it must be of the same form as the protobuf
                message :class:`~google.cloud.logging_v2.types.LogEntry`
            log_name (str): Optional. A default log resource name that is assigned to all log
                entries in ``entries`` that do not specify a value for ``log_name``:

                ::

                     "projects/[PROJECT_ID]/logs/[LOG_ID]"
                     "organizations/[ORGANIZATION_ID]/logs/[LOG_ID]"
                     "billingAccounts/[BILLING_ACCOUNT_ID]/logs/[LOG_ID]"
                     "folders/[FOLDER_ID]/logs/[LOG_ID]"

                ``[LOG_ID]`` must be URL-encoded. For example:

                ::

                     "projects/my-project-id/logs/syslog"
                     "organizations/1234567890/logs/cloudresourcemanager.googleapis.com%2Factivity"

                The permission logging.logEntries.create is needed on each project,
                organization, billing account, or folder that is receiving new log
                entries, whether the resource is specified in logName or in an
                individual log entry.
            resource (Union[dict, ~google.cloud.logging_v2.types.MonitoredResource]): Optional. A default monitored resource object that is assigned to all
                log entries in ``entries`` that do not specify a value for ``resource``.
                Example:

                ::

                     { "type": "gce_instance",
                       "labels": {
                         "zone": "us-central1-a", "instance_id": "00000000000000000000" }}

                See ``LogEntry``.

                If a dict is provided, it must be of the same form as the protobuf
                message :class:`~google.cloud.logging_v2.types.MonitoredResource`
            labels (dict[str -> str]): Optional. Default labels that are added to the ``labels`` field of all
                log entries in ``entries``. If a log entry already has a label with the
                same key as a label in this parameter, then the log entry's label is not
                changed. See ``LogEntry``.
            partial_success (bool): Optional. Whether valid entries should be written even if some other
                entries fail due to INVALID\_ARGUMENT or PERMISSION\_DENIED errors. If
                any entry is not written, then the response status is the error
                associated with one of the failed entries and the response includes
                error details keyed by the entries' zero-based index in the
                ``entries.write`` method.
            dry_run (bool): Optional. If true, the request should expect normal response, but the
                entries won't be persisted nor exported. Useful for checking whether the
                logging API endpoints are working properly before sending valuable data.
            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.logging_v2.types.WriteLogEntriesResponse` 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 "write_log_entries" not in self._inner_api_calls:
            self._inner_api_calls[
                "write_log_entries"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.write_log_entries,
                default_retry=self._method_configs["WriteLogEntries"].retry,
                default_timeout=self._method_configs["WriteLogEntries"].timeout,
                client_info=self._client_info,
            )

        request = logging_pb2.WriteLogEntriesRequest(
            entries=entries,
            log_name=log_name,
            resource=resource,
            labels=labels,
            partial_success=partial_success,
            dry_run=dry_run,
        )
        return self._inner_api_calls["write_log_entries"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )

    def list_log_entries(
        self,
        resource_names,
        project_ids=None,
        filter_=None,
        order_by=None,
        page_size=None,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Lists log entries. Use this method to retrieve log entries that
        originated from a project/folder/organization/billing account. For ways
        to export log entries, see `Exporting
        Logs <https://cloud.google.com/logging/docs/export>`__.

        Example:
            >>> from google.cloud import logging_v2
            >>>
            >>> client = logging_v2.LoggingServiceV2Client()
            >>>
            >>> # TODO: Initialize `resource_names`:
            >>> resource_names = []
            >>>
            >>> # Iterate over all results
            >>> for element in client.list_log_entries(resource_names):
            ...     # process element
            ...     pass
            >>>
            >>>
            >>> # Alternatively:
            >>>
            >>> # Iterate over results one page at a time
            >>> for page in client.list_log_entries(resource_names).pages:
            ...     for element in page:
            ...         # process element
            ...         pass

        Args:
            resource_names (list[str]): Required. Names of one or more parent resources from which to retrieve
                log entries:

                ::

                     "projects/[PROJECT_ID]"
                     "organizations/[ORGANIZATION_ID]"
                     "billingAccounts/[BILLING_ACCOUNT_ID]"
                     "folders/[FOLDER_ID]"

                Projects listed in the ``project_ids`` field are added to this list.
            project_ids (list[str]): Deprecated. Use ``resource_names`` instead. One or more project
                identifiers or project numbers from which to retrieve log entries.
                Example: ``"my-project-1A"``.
            filter_ (str): Optional. A filter that chooses which log entries to return. See
                `Advanced Logs
                Queries <https://cloud.google.com/logging/docs/view/advanced-queries>`__.
                Only log entries that match the filter are returned. An empty filter
                matches all log entries in the resources listed in ``resource_names``.
                Referencing a parent resource that is not listed in ``resource_names``
                will cause the filter to return no results. The maximum length of the
                filter is 20000 characters.
            order_by (str): Optional. How the results should be sorted. Presently, the only
                permitted values are ``"timestamp asc"`` (default) and
                ``"timestamp desc"``. The first option returns entries in order of
                increasing values of ``LogEntry.timestamp`` (oldest first), and the
                second option returns entries in order of decreasing timestamps (newest
                first). Entries with equal timestamps are returned in order of their
                ``insert_id`` values.
            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.logging_v2.types.LogEntry` 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_log_entries" not in self._inner_api_calls:
            self._inner_api_calls[
                "list_log_entries"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.list_log_entries,
                default_retry=self._method_configs["ListLogEntries"].retry,
                default_timeout=self._method_configs["ListLogEntries"].timeout,
                client_info=self._client_info,
            )

        request = logging_pb2.ListLogEntriesRequest(
            resource_names=resource_names,
            project_ids=project_ids,
            filter=filter_,
            order_by=order_by,
            page_size=page_size,
        )
        iterator = google.api_core.page_iterator.GRPCIterator(
            client=None,
            method=functools.partial(
                self._inner_api_calls["list_log_entries"],
                retry=retry,
                timeout=timeout,
                metadata=metadata,
            ),
            request=request,
            items_field="entries",
            request_token_field="page_token",
            response_token_field="next_page_token",
        )
        return iterator

    def list_monitored_resource_descriptors(
        self,
        page_size=None,
        retry=google.api_core.gapic_v1.method.DEFAULT,
        timeout=google.api_core.gapic_v1.method.DEFAULT,
        metadata=None,
    ):
        """
        Lists the descriptors for monitored resource types used by Logging.

        Example:
            >>> from google.cloud import logging_v2
            >>>
            >>> client = logging_v2.LoggingServiceV2Client()
            >>>
            >>> # Iterate over all results
            >>> for element in client.list_monitored_resource_descriptors():
            ...     # process element
            ...     pass
            >>>
            >>>
            >>> # Alternatively:
            >>>
            >>> # Iterate over results one page at a time
            >>> for page in client.list_monitored_resource_descriptors().pages:
            ...     for element in page:
            ...         # process element
            ...         pass

        Args:
            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.logging_v2.types.MonitoredResourceDescriptor` 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_monitored_resource_descriptors" not in self._inner_api_calls:
            self._inner_api_calls[
                "list_monitored_resource_descriptors"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.list_monitored_resource_descriptors,
                default_retry=self._method_configs[
                    "ListMonitoredResourceDescriptors"
                ].retry,
                default_timeout=self._method_configs[
                    "ListMonitoredResourceDescriptors"
                ].timeout,
                client_info=self._client_info,
            )

        request = logging_pb2.ListMonitoredResourceDescriptorsRequest(
            page_size=page_size,
        )
        iterator = google.api_core.page_iterator.GRPCIterator(
            client=None,
            method=functools.partial(
                self._inner_api_calls["list_monitored_resource_descriptors"],
                retry=retry,
                timeout=timeout,
                metadata=metadata,
            ),
            request=request,
            items_field="resource_descriptors",
            request_token_field="page_token",
            response_token_field="next_page_token",
        )
        return iterator

    def list_logs(
        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 logs in projects, organizations, folders, or billing accounts.
        Only logs that have entries are listed.

        Example:
            >>> from google.cloud import logging_v2
            >>>
            >>> client = logging_v2.LoggingServiceV2Client()
            >>>
            >>> parent = client.project_path('[PROJECT]')
            >>>
            >>> # Iterate over all results
            >>> for element in client.list_logs(parent):
            ...     # process element
            ...     pass
            >>>
            >>>
            >>> # Alternatively:
            >>>
            >>> # Iterate over results one page at a time
            >>> for page in client.list_logs(parent).pages:
            ...     for element in page:
            ...         # process element
            ...         pass

        Args:
            parent (str): Required. The resource name that owns the logs:

                ::

                     "projects/[PROJECT_ID]"
                     "organizations/[ORGANIZATION_ID]"
                     "billingAccounts/[BILLING_ACCOUNT_ID]"
                     "folders/[FOLDER_ID]"
            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:`str` 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_logs" not in self._inner_api_calls:
            self._inner_api_calls[
                "list_logs"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.list_logs,
                default_retry=self._method_configs["ListLogs"].retry,
                default_timeout=self._method_configs["ListLogs"].timeout,
                client_info=self._client_info,
            )

        request = logging_pb2.ListLogsRequest(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_logs"],
                retry=retry,
                timeout=timeout,
                metadata=metadata,
            ),
            request=request,
            items_field="log_names",
            request_token_field="page_token",
            response_token_field="next_page_token",
        )
        return iterator