Create and manage notification channels by API

static void RestorePolicies(string projectId, string filePath)
{
    var policyClient = AlertPolicyServiceClient.Create();
    var channelClient = NotificationChannelServiceClient.Create();
    List<Exception> exceptions = new List<Exception>();
    var backup = JsonConvert.DeserializeObject<BackupRecord>(
        File.ReadAllText(filePath), new ProtoMessageConverter());
    var projectName = new ProjectName(projectId);
    bool isSameProject = projectId == backup.ProjectId;
    // When a channel is recreated, rather than updated, it will get
    // a new name.  We have to update the AlertPolicy with the new
    // name.  Track the names in this map.
    var channelNameMap = new Dictionary<string, string>();
    foreach (NotificationChannel channel in backup.Channels)
    {
        try
        {
            bool updated = false;
            Console.WriteLine("Updating channel.\n{0}",
                channel.DisplayName);
            // This field is immutable and it is illegal to specify a
            // non-default value (UNVERIFIED or VERIFIED) in the
            // Create() or Update() operations.
            channel.VerificationStatus = NotificationChannel.Types
                .VerificationStatus.Unspecified;
            if (isSameProject)
                try
                {
                    channelClient.UpdateNotificationChannel(
                        null, channel);
                    updated = true;
                }
                catch (Grpc.Core.RpcException e)
                when (e.Status.StatusCode == StatusCode.NotFound)
                { }
            if (!updated)
            {
                // The channel no longer exists.  Recreate it.
                string oldName = channel.Name;
                channel.Name = null;
                var response = channelClient.CreateNotificationChannel(
                    projectName, channel);
                channelNameMap.Add(oldName, response.Name);
            }
        }
        catch (Exception e)
        {
            // If one failed, continue trying to update the others.
            exceptions.Add(e);
        }
    }
    foreach (AlertPolicy policy in backup.Policies)
    {
    }
    if (exceptions.Count > 0)
    {
        throw new AggregateException(exceptions);
    }
}

// Imports the Google Cloud client library
const monitoring = require('@google-cloud/monitoring');

// Creates clients
const alertClient = new monitoring.AlertPolicyServiceClient();
const notificationClient = new monitoring.NotificationChannelServiceClient();

async function replaceChannels() {
  /**
   * TODO(developer): Uncomment the following lines before running the sample.
   */
  // const projectId = 'YOUR_PROJECT_ID';
  // const alertPolicyId = '123456789012314';
  // const channelIds = [
  //   'channel-1',
  //   'channel-2',
  //   'channel-3',
  // ];

  const notificationChannels = channelIds.map(id =>
    notificationClient.projectNotificationChannelPath(projectId, id)
  );

  for (const channel of notificationChannels) {
    const updateChannelRequest = {
      updateMask: {
        paths: ['enabled'],
      },
      notificationChannel: {
        name: channel,
        enabled: {
          value: true,
        },
      },
    };
    try {
      await notificationClient.updateNotificationChannel(
        updateChannelRequest
      );
    } catch (err) {
      const createChannelRequest = {
        notificationChannel: {
          name: channel,
          notificationChannel: {
            type: 'email',
          },
        },
      };
      const newChannel =
        await notificationClient.createNotificationChannel(
          createChannelRequest
        );
      notificationChannels.push(newChannel);
    }
  }

  const updateAlertPolicyRequest = {
    updateMask: {
      paths: ['notification_channels'],
    },
    alertPolicy: {
      name: alertClient.projectAlertPolicyPath(projectId, alertPolicyId),
      notificationChannels: notificationChannels,
    },
  };
  const [alertPolicy] = await alertClient.updateAlertPolicy(
    updateAlertPolicyRequest
  );
  console.log(`Updated ${alertPolicy.name}.`);
}
replaceChannels();

// restorePolicies updates the project with the alert policies and
// notification channels in r.
func restorePolicies(w io.Writer, projectID string, r io.Reader) error {
	b := backup{}
	if err := json.NewDecoder(r).Decode(&b); err != nil {
		return err
	}
	sameProject := projectID == b.ProjectID

	ctx := context.Background()

	alertClient, err := monitoring.NewAlertPolicyClient(ctx)
	if err != nil {
		return err
	}
	defer alertClient.Close()
	channelClient, err := monitoring.NewNotificationChannelClient(ctx)
	if err != nil {
		return err
	}
	defer channelClient.Close()

	// When a channel is recreated, rather than updated, it will get
	// a new name.  We have to update the AlertPolicy with the new
	// name.  channelNames keeps track of the new names.
	channelNames := make(map[string]string)
	for _, c := range b.Channels {
		fmt.Fprintf(w, "Updating channel %q\n", c.GetDisplayName())
		c.VerificationStatus = monitoringpb.NotificationChannel_VERIFICATION_STATUS_UNSPECIFIED
		updated := false
		if sameProject {
			req := &monitoringpb.UpdateNotificationChannelRequest{
				NotificationChannel: c.NotificationChannel,
			}
			_, err := channelClient.UpdateNotificationChannel(ctx, req)
			if err == nil {
				updated = true
			}
		}
		if !updated {
			req := &monitoringpb.CreateNotificationChannelRequest{
				Name:                "projects/" + projectID,
				NotificationChannel: c.NotificationChannel,
			}
			oldName := c.GetName()
			c.Name = ""
			newC, err := channelClient.CreateNotificationChannel(ctx, req)
			if err != nil {
				return err
			}
			channelNames[oldName] = newC.GetName()
		}
	}

	for _, policy := range b.AlertPolicies {
		fmt.Fprintf(w, "Updating alert %q\n", policy.GetDisplayName())
		policy.CreationRecord = nil
		policy.MutationRecord = nil
		for i, aChannel := range policy.GetNotificationChannels() {
			if c, ok := channelNames[aChannel]; ok {
				policy.NotificationChannels[i] = c
			}
		}
		updated := false
		if sameProject {
			req := &monitoringpb.UpdateAlertPolicyRequest{
				AlertPolicy: policy.AlertPolicy,
			}
			_, err := alertClient.UpdateAlertPolicy(ctx, req)
			if err == nil {
				updated = true
			}
		}
		if !updated {
			req := &monitoringpb.CreateAlertPolicyRequest{
				Name:        "projects/" + projectID,
				AlertPolicy: policy.AlertPolicy,
			}
			if _, err = alertClient.CreateAlertPolicy(ctx, req); err != nil {
				log.Fatal(err)
			}
		}
	}
	fmt.Fprintf(w, "Successfully restored alerts.")
	return nil
}

private static Map<String, String> restoreNotificationChannels(
    String projectId, List<NotificationChannel> channels, boolean isSameProject)
    throws IOException {
  Map<String, String> newChannelNames = Maps.newHashMap();
  try (NotificationChannelServiceClient client = NotificationChannelServiceClient.create()) {
    for (NotificationChannel channel : channels) {
      // Update channel name if project ID is different.
      boolean channelUpdated = false;
      if (isSameProject) {
        try {
          NotificationChannel updatedChannel =
              client.updateNotificationChannel(NOTIFICATION_CHANNEL_UPDATE_MASK, channel);
          newChannelNames.put(channel.getName(), updatedChannel.getName());
          channelUpdated = true;
        } catch (Exception e) {
          channelUpdated = false;
        }
      }
      if (!channelUpdated) {
        NotificationChannel newChannel =
            client.createNotificationChannel(
                ProjectName.of(projectId),
                channel.toBuilder().clearName().clearVerificationStatus().build());
        newChannelNames.put(channel.getName(), newChannel.getName());
      }
    }
  }
  return newChannelNames;
}

use Google\Cloud\Monitoring\V3\Client\NotificationChannelServiceClient;
use Google\Cloud\Monitoring\V3\CreateNotificationChannelRequest;
use Google\Cloud\Monitoring\V3\NotificationChannel;

/**
 * @param string $projectId Your project ID
 */
function alert_create_channel(string $projectId): void
{
    $channelClient = new NotificationChannelServiceClient([
        'projectId' => $projectId,
    ]);
    $projectName = 'projects/' . $projectId;

    $channel = new NotificationChannel();
    $channel->setDisplayName('Test Notification Channel');
    $channel->setType('email');
    $channel->setLabels(['email_address' => 'fake@example.com']);
    $createNotificationChannelRequest = (new CreateNotificationChannelRequest())
        ->setName($projectName)
        ->setNotificationChannel($channel);

    $channel = $channelClient->createNotificationChannel($createNotificationChannelRequest);
    printf('Created notification channel %s' . PHP_EOL, $channel->getName());
}

def restore(project_name, backup_filename):
    """Restore alert policies in a project.

    Arguments:
        project_name (str): The Google Cloud Project to use. The project name
            must be in the format - 'projects/<PROJECT_NAME>'.
        backup_filename (str): Name of the file (along with its path) from
            which the alert policies will be restored.
    """
    print(
        "Loading alert policies and notification channels from {}.".format(
            backup_filename
        )
    )
    record = json.load(open(backup_filename, "rt"))
    is_same_project = project_name == record["project_name"]
    # Convert dicts to AlertPolicies.
    policies_json = [json.dumps(policy) for policy in record["policies"]]
    policies = [
        monitoring_v3.AlertPolicy.from_json(policy_json)
        for policy_json in policies_json
    ]
    # Convert dicts to NotificationChannels
    channels_json = [json.dumps(channel) for channel in record["channels"]]
    channels = [
        monitoring_v3.NotificationChannel.from_json(channel_json)
        for channel_json in channels_json
    ]

    # Restore the channels.
    channel_client = monitoring_v3.NotificationChannelServiceClient()
    channel_name_map = {}

    for channel in channels:
        updated = False
        print("Updating channel", channel.display_name)
        # This field is immutable and it is illegal to specify a
        # non-default value (UNVERIFIED or VERIFIED) in the
        # Create() or Update() operations.
        channel.verification_status = (
            monitoring_v3.NotificationChannel.VerificationStatus.VERIFICATION_STATUS_UNSPECIFIED
        )

        if is_same_project:
            try:
                channel_client.update_notification_channel(notification_channel=channel)
                updated = True
            except google.api_core.exceptions.NotFound:
                pass  # The channel was deleted.  Create it below.

        if not updated:
            # The channel no longer exists.  Recreate it.
            old_name = channel.name
            del channel.name
            new_channel = channel_client.create_notification_channel(
                name=project_name, notification_channel=channel
            )
            channel_name_map[old_name] = new_channel.name

    # Restore the alerts
    alert_client = monitoring_v3.AlertPolicyServiceClient()

    for policy in policies:
        print("Updating policy", policy.display_name)
        # These two fields cannot be set directly, so clear them.
        del policy.creation_record
        del policy.mutation_record

        # Update old channel names with new channel names.
        for i, channel in enumerate(policy.notification_channels):
            new_channel = channel_name_map.get(channel)
            if new_channel:
                policy.notification_channels[i] = new_channel

        updated = False

        if is_same_project:
            try:
                alert_client.update_alert_policy(alert_policy=policy)
                updated = True
            except google.api_core.exceptions.NotFound:
                pass  # The policy was deleted.  Create it below.
            except google.api_core.exceptions.InvalidArgument:
                # Annoying that API throws InvalidArgument when the policy
                # does not exist.  Seems like it should throw NotFound.
                pass  # The policy was deleted.  Create it below.

        if not updated:
            # The policy no longer exists.  Recreate it.
            old_name = policy.name
            del policy.name
            for condition in policy.conditions:
                del condition.name
            policy = alert_client.create_alert_policy(
                name=project_name, alert_policy=policy
            )
        print("Updated", policy.name)

static void ListNotificationChannels(string projectId)
{
    var client = NotificationChannelServiceClient.Create();
    var response = client.ListNotificationChannels(new ProjectName(projectId));
    foreach (NotificationChannel channel in response)
    {
        Console.WriteLine(channel.Name);
        if (channel.DisplayName != null)
        {
            Console.WriteLine(channel.DisplayName);
        }
        Console.WriteLine();
    }
}

// Imports the Google Cloud client library
const monitoring = require('@google-cloud/monitoring');

// Creates a client
const client = new monitoring.NotificationChannelServiceClient();

async function deleteChannels() {
  /**
   * TODO(developer): Uncomment the following lines before running the sample.
   */
  // const projectId = 'YOUR_PROJECT_ID';
  // const filter = 'A filter for selecting policies, e.g. description:"cloud"';

  const request = {
    name: client.projectPath(projectId),
    filter,
  };
  const channels = await client.listNotificationChannels(request);
  console.log(channels);
  for (const channel of channels[0]) {
    console.log(`Deleting channel ${channel.displayName}`);
    try {
      await client.deleteNotificationChannel({
        name: channel.name,
      });
    } catch (err) {
      // ignore error
    }
  }
}
deleteChannels();

channelClient, err := monitoring.NewNotificationChannelClient(ctx)
if err != nil {
	return err
}
defer channelClient.Close()
channelReq := &monitoringpb.ListNotificationChannelsRequest{
	Name: "projects/" + projectID,
	// Filter:  "", // See https://cloud.google.com/monitoring/api/v3/sorting-and-filtering.
	// OrderBy: "", // See https://cloud.google.com/monitoring/api/v3/sorting-and-filtering.
}
channelIt := channelClient.ListNotificationChannels(ctx, channelReq)
for {
	resp, err := channelIt.Next()
	if err == iterator.Done {
		break
	}
	if err != nil {
		return err
	}
	b.Channels = append(b.Channels, &channel{resp})
}

private static List<NotificationChannel> getNotificationChannels(String projectId)
    throws IOException {
  List<NotificationChannel> notificationChannels = Lists.newArrayList();
  try (NotificationChannelServiceClient client = NotificationChannelServiceClient.create()) {
    ListNotificationChannelsPagedResponse listNotificationChannelsResponse =
        client.listNotificationChannels(ProjectName.of(projectId));
    for (NotificationChannel channel : listNotificationChannelsResponse.iterateAll()) {
      notificationChannels.add(channel);
    }
  }
  return notificationChannels;
}

use Google\Cloud\Monitoring\V3\Client\NotificationChannelServiceClient;
use Google\Cloud\Monitoring\V3\ListNotificationChannelsRequest;

/**
 * @param string $projectId Your project ID
 */
function alert_list_channels($projectId)
{
    $projectName = 'projects/' . $projectId;
    $channelClient = new NotificationChannelServiceClient([
        'projectId' => $projectId,
    ]);
    $listNotificationChannelsRequest = (new ListNotificationChannelsRequest())
        ->setName($projectName);

    $channels = $channelClient->listNotificationChannels($listNotificationChannelsRequest);
    foreach ($channels->iterateAllElements() as $channel) {
        printf('Name: %s (%s)' . PHP_EOL, $channel->getDisplayName(), $channel->getName());
    }
}

def list_notification_channels(project_name):
    """List alert notification channels in a project.

    Arguments:
        project_name (str): The Google Cloud Project to use. The project name
            must be in the format - 'projects/<PROJECT_NAME>'.
    """

    client = monitoring_v3.NotificationChannelServiceClient()
    channels = client.list_notification_channels(name=project_name)
    print(
        tabulate.tabulate(
            [(channel.name, channel.display_name) for channel in channels],
            ("name", "display_name"),
        )
    )

using Google.Cloud.Monitoring.V3;
using System;

partial class AlertSnippets
{
    public void DeleteNotificationChannel(
        string channelName = "projects/your-project-id/notificationChannels/123")
    {
        var client = NotificationChannelServiceClient.Create();
        client.DeleteNotificationChannel(
            name: NotificationChannelName.Parse(channelName),
            force: true);
        Console.WriteLine("Deleted {0}.", channelName);
    }
}

import (
	"context"
	"fmt"
	"io"

	monitoring "cloud.google.com/go/monitoring/apiv3"
	"cloud.google.com/go/monitoring/apiv3/v2/monitoringpb"
)

// deleteChannel deletes the given channel. channelName should be of the form
// "projects/[PROJECT_ID]/notificationChannels/[CHANNEL_ID]".
func deleteChannel(w io.Writer, channelName string) error {
	ctx := context.Background()

	client, err := monitoring.NewNotificationChannelClient(ctx)
	if err != nil {
		return err
	}
	defer client.Close()

	req := &monitoringpb.DeleteNotificationChannelRequest{
		Name: channelName,
	}

	if err := client.DeleteNotificationChannel(ctx, req); err != nil {
		return fmt.Errorf("DeleteNotificationChannel: %w", err)
	}

	fmt.Fprintf(w, "Deleted channel %q", channelName)
	return nil
}

static void deleteNotificationChannel(String channelName) throws IOException {
  String projectId = System.getProperty("projectId");
  try (NotificationChannelServiceClient client = NotificationChannelServiceClient.create()) {
    NotificationChannelName name = NotificationChannelName.of(projectId, channelName);
    client.deleteNotificationChannel(channelName, false);
    System.out.println("Deleted notification channel " + channelName);
  }
}

use Google\Cloud\Monitoring\V3\Client\NotificationChannelServiceClient;
use Google\Cloud\Monitoring\V3\DeleteNotificationChannelRequest;

/**
 * @param string $projectId Your project ID
 * @param string $channelId
 */
function alert_delete_channel(string $projectId, string $channelId): void
{
    $channelClient = new NotificationChannelServiceClient([
        'projectId' => $projectId,
    ]);
    $channelName = $channelClient->notificationChannelName($projectId, $channelId);
    $deleteNotificationChannelRequest = (new DeleteNotificationChannelRequest())
        ->setName($channelName);

    $channelClient->deleteNotificationChannel($deleteNotificationChannelRequest);
    printf('Deleted notification channel %s' . PHP_EOL, $channelName);
}

// Imports the Google Cloud client library
const monitoring = require('@google-cloud/monitoring');

// Creates a client
const client = new monitoring.NotificationChannelServiceClient();

async function deleteChannels() {
  /**
   * TODO(developer): Uncomment the following lines before running the sample.
   */
  // const projectId = 'YOUR_PROJECT_ID';
  // const filter = 'A filter for selecting policies, e.g. description:"cloud"';

  const request = {
    name: client.projectPath(projectId),
    filter,
  };
  const channels = await client.listNotificationChannels(request);
  console.log(channels);
  for (const channel of channels[0]) {
    console.log(`Deleting channel ${channel.displayName}`);
    try {
      await client.deleteNotificationChannel({
        name: channel.name,
      });
    } catch (err) {
      // ignore error
    }
  }
}
deleteChannels();

def delete_notification_channels(project_name, channel_ids, force=None):
    """Delete alert notification channels.

    Arguments:
        project_name (str): The Google Cloud Project to use. The project name
            must be in the format - 'projects/<PROJECT_NAME>'.
        channel_ids list(str): List of IDs of notification channels to delete.
        force (bool): If true, the notification channels are deleted regardless
            of its in use by alert policies. If false, channels that are still
            referenced by an existing alerting policy will fail to be deleted.
    """

    channel_client = monitoring_v3.NotificationChannelServiceClient()
    for channel_id in channel_ids:
        channel_name = "{}/notificationChannels/{}".format(project_name, channel_id)
        try:
            channel_client.delete_notification_channel(name=channel_name, force=force)
            print("Channel {} deleted".format(channel_name))
        except ValueError:
            print("The parameters are invalid")
        except Exception as e:
            print("API call failed: {}".format(e))

using Google.Cloud.Monitoring.V3;
using Google.Protobuf.WellKnownTypes;
using System;

partial class AlertSnippets
{
    public NotificationChannel EnableNotificationChannel(
        string channelName = "projects/your-project-id/notificationChannels/123")
    {
        var client = NotificationChannelServiceClient.Create();
        NotificationChannel channel = new NotificationChannel();
        channel.Enabled = true;
        channel.Name = channelName;
        var fieldMask = new FieldMask { Paths = { "enabled" } };
        channel = client.UpdateNotificationChannel(
            updateMask: fieldMask,
            notificationChannel: channel);
        Console.WriteLine("Enabled {0}.", channel.Name);
        return channel;
    }
}

import (
	"context"
	"fmt"
	"io"

	monitoring "cloud.google.com/go/monitoring/apiv3"
	"cloud.google.com/go/monitoring/apiv3/v2/monitoringpb"
	"github.com/golang/protobuf/ptypes/wrappers"
	"google.golang.org/genproto/protobuf/field_mask"
)

// enableChannel enables the given channel. channelName should be of the form
// "projects/[PROJECT_ID]/notificationChannels/[CHANNEL_ID]".
func enableChannel(w io.Writer, channelName string) error {
	ctx := context.Background()

	client, err := monitoring.NewNotificationChannelClient(ctx)
	if err != nil {
		return err
	}
	defer client.Close()

	req := &monitoringpb.UpdateNotificationChannelRequest{
		UpdateMask: &field_mask.FieldMask{Paths: []string{"enabled"}},
		NotificationChannel: &monitoringpb.NotificationChannel{
			Name:    channelName,
			Enabled: &wrappers.BoolValue{Value: true},
		},
	}

	if _, err := client.UpdateNotificationChannel(ctx, req); err != nil {
		return fmt.Errorf("EnableNotificationChannel: %w", err)
	}

	fmt.Fprintf(w, "Enabled channel %q", channelName)
	return nil
}

// Imports the Google Cloud client library
const monitoring = require('@google-cloud/monitoring');

// Creates clients
const alertClient = new monitoring.AlertPolicyServiceClient();
const notificationClient = new monitoring.NotificationChannelServiceClient();

async function replaceChannels() {
  /**
   * TODO(developer): Uncomment the following lines before running the sample.
   */
  // const projectId = 'YOUR_PROJECT_ID';
  // const alertPolicyId = '123456789012314';
  // const channelIds = [
  //   'channel-1',
  //   'channel-2',
  //   'channel-3',
  // ];

  const notificationChannels = channelIds.map(id =>
    notificationClient.projectNotificationChannelPath(projectId, id)
  );

  for (const channel of notificationChannels) {
    const updateChannelRequest = {
      updateMask: {
        paths: ['enabled'],
      },
      notificationChannel: {
        name: channel,
        enabled: {
          value: true,
        },
      },
    };
    try {
      await notificationClient.updateNotificationChannel(
        updateChannelRequest
      );
    } catch (err) {
      const createChannelRequest = {
        notificationChannel: {
          name: channel,
          notificationChannel: {
            type: 'email',
          },
        },
      };
      const newChannel =
        await notificationClient.createNotificationChannel(
          createChannelRequest
        );
      notificationChannels.push(newChannel);
    }
  }

  const updateAlertPolicyRequest = {
    updateMask: {
      paths: ['notification_channels'],
    },
    alertPolicy: {
      name: alertClient.projectAlertPolicyPath(projectId, alertPolicyId),
      notificationChannels: notificationChannels,
    },
  };
  const [alertPolicy] = await alertClient.updateAlertPolicy(
    updateAlertPolicyRequest
  );
  console.log(`Updated ${alertPolicy.name}.`);
}
replaceChannels();

private static Map<String, String> restoreNotificationChannels(
    String projectId, List<NotificationChannel> channels, boolean isSameProject)
    throws IOException {
  Map<String, String> newChannelNames = Maps.newHashMap();
  try (NotificationChannelServiceClient client = NotificationChannelServiceClient.create()) {
    for (NotificationChannel channel : channels) {
      // Update channel name if project ID is different.
      boolean channelUpdated = false;
      if (isSameProject) {
        try {
          NotificationChannel updatedChannel =
              client.updateNotificationChannel(NOTIFICATION_CHANNEL_UPDATE_MASK, channel);
          newChannelNames.put(channel.getName(), updatedChannel.getName());
          channelUpdated = true;
        } catch (Exception e) {
          channelUpdated = false;
        }
      }
      if (!channelUpdated) {
        NotificationChannel newChannel =
            client.createNotificationChannel(
                ProjectName.of(projectId),
                channel.toBuilder().clearName().clearVerificationStatus().build());
        newChannelNames.put(channel.getName(), newChannel.getName());
      }
    }
  }
  return newChannelNames;
}

use Google\ApiCore\ApiException;
use Google\Cloud\Monitoring\V3\AlertPolicy;
use Google\Cloud\Monitoring\V3\Client\AlertPolicyServiceClient;
use Google\Cloud\Monitoring\V3\Client\NotificationChannelServiceClient;
use Google\Cloud\Monitoring\V3\CreateAlertPolicyRequest;
use Google\Cloud\Monitoring\V3\CreateNotificationChannelRequest;
use Google\Cloud\Monitoring\V3\NotificationChannel;
use Google\Cloud\Monitoring\V3\NotificationChannel\VerificationStatus;
use Google\Cloud\Monitoring\V3\UpdateAlertPolicyRequest;
use Google\Cloud\Monitoring\V3\UpdateNotificationChannelRequest;

/**
 * @param string $projectId Your project ID
 */
function alert_restore_policies(string $projectId): void
{
    $alertClient = new AlertPolicyServiceClient([
        'projectId' => $projectId,
    ]);

    $channelClient = new NotificationChannelServiceClient([
        'projectId' => $projectId,
    ]);

    print('Loading alert policies and notification channels from backup.json.' . PHP_EOL);
    $projectName = 'projects/' . $projectId;
    $record = json_decode((string) file_get_contents('backup.json'), true);
    $isSameProject = $projectName == $record['project_name'];

    # Convert dicts to AlertPolicies.
    $policies = [];
    foreach ($record['policies'] as $policyArray) {
        $policy = new AlertPolicy();
        $policy->mergeFromJsonString((string) json_encode($policyArray));
        $policies[] = $policy;
    }

    # Convert dicts to NotificationChannels
    $channels = [];
    foreach (array_filter($record['channels']) as $channelArray) {
        $channel = new NotificationChannel();
        $channel->mergeFromJsonString((string) json_encode($channelArray));
        $channels[] = $channel;
    }

    # Restore the channels.
    $channelNameMap = [];
    foreach ($channels as $channel) {
        $updated = false;
        printf('Updating channel %s' . PHP_EOL, $channel->getDisplayName());

        # This field is immutable and it is illegal to specify a
        # non-default value (UNVERIFIED or VERIFIED) in the
        # Create() or Update() operations.
        $channel->setVerificationStatus(
            VerificationStatus::VERIFICATION_STATUS_UNSPECIFIED
        );

        if ($isSameProject) {
            try {
                $updateNotificationChannelRequest = (new UpdateNotificationChannelRequest())
                    ->setNotificationChannel($channel);
                $channelClient->updateNotificationChannel($updateNotificationChannelRequest);
                $updated = true;
            } catch (ApiException $e) {
                # The channel was deleted.  Create it below.
                if ($e->getStatus() !== 'NOT_FOUND') {
                    throw $e;
                }
            }
        }

        if (!$updated) {
            # The channel no longer exists.  Recreate it.
            $oldName = $channel->getName();
            $channel->setName('');
            $createNotificationChannelRequest = (new CreateNotificationChannelRequest())
                ->setName($projectName)
                ->setNotificationChannel($channel);
            $newChannel = $channelClient->createNotificationChannel($createNotificationChannelRequest);
            $channelNameMap[$oldName] = $newChannel->getName();
        }
    }

    # Restore the alerts
    foreach ($policies as $policy) {
        printf('Updating policy %s' . PHP_EOL, $policy->getDisplayName());
        # These two fields cannot be set directly, so clear them.
        $policy->clearCreationRecord();
        $policy->clearMutationRecord();

        $notificationChannels = $policy->getNotificationChannels();

        # Update old channel names with new channel names.
        foreach ($notificationChannels as $i => $channel) {
            if (isset($channelNameMap[$channel])) {
                $notificationChannels[$i] = $channelNameMap[$channel];
            }
        }

        $updated = false;
        if ($isSameProject) {
            try {
                $updateAlertPolicyRequest = (new UpdateAlertPolicyRequest())
                    ->setAlertPolicy($policy);
                $alertClient->updateAlertPolicy($updateAlertPolicyRequest);
                $updated = true;
            } catch (ApiException $e) {
                # The policy was deleted.  Create it below.
                if ($e->getStatus() !== 'NOT_FOUND') {
                    throw $e;
                }
            }
        }

        if (!$updated) {
            # The policy no longer exists.  Recreate it.
            $oldName = $policy->getName();
            $policy->setName('');
            foreach ($policy->getConditions() as $condition) {
                $condition->setName('');
            }
            $createAlertPolicyRequest = (new CreateAlertPolicyRequest())
                ->setName($projectName)
                ->setAlertPolicy($policy);
            $policy = $alertClient->createAlertPolicy($createAlertPolicyRequest);
        }
        printf('Updated %s' . PHP_EOL, $policy->getName());
    }
    print('Restored alert policies and notification channels from backup.json.');
}

def restore(project_name, backup_filename):
    """Restore alert policies in a project.

    Arguments:
        project_name (str): The Google Cloud Project to use. The project name
            must be in the format - 'projects/<PROJECT_NAME>'.
        backup_filename (str): Name of the file (along with its path) from
            which the alert policies will be restored.
    """
    print(
        "Loading alert policies and notification channels from {}.".format(
            backup_filename
        )
    )
    record = json.load(open(backup_filename, "rt"))
    is_same_project = project_name == record["project_name"]
    # Convert dicts to AlertPolicies.
    policies_json = [json.dumps(policy) for policy in record["policies"]]
    policies = [
        monitoring_v3.AlertPolicy.from_json(policy_json)
        for policy_json in policies_json
    ]
    # Convert dicts to NotificationChannels
    channels_json = [json.dumps(channel) for channel in record["channels"]]
    channels = [
        monitoring_v3.NotificationChannel.from_json(channel_json)
        for channel_json in channels_json
    ]

    # Restore the channels.
    channel_client = monitoring_v3.NotificationChannelServiceClient()
    channel_name_map = {}

    for channel in channels:
        updated = False
        print("Updating channel", channel.display_name)
        # This field is immutable and it is illegal to specify a
        # non-default value (UNVERIFIED or VERIFIED) in the
        # Create() or Update() operations.
        channel.verification_status = (
            monitoring_v3.NotificationChannel.VerificationStatus.VERIFICATION_STATUS_UNSPECIFIED
        )

        if is_same_project:
            try:
                channel_client.update_notification_channel(notification_channel=channel)
                updated = True
            except google.api_core.exceptions.NotFound:
                pass  # The channel was deleted.  Create it below.

        if not updated:
            # The channel no longer exists.  Recreate it.
            old_name = channel.name
            del channel.name
            new_channel = channel_client.create_notification_channel(
                name=project_name, notification_channel=channel
            )
            channel_name_map[old_name] = new_channel.name

    # Restore the alerts
    alert_client = monitoring_v3.AlertPolicyServiceClient()

    for policy in policies:
        print("Updating policy", policy.display_name)
        # These two fields cannot be set directly, so clear them.
        del policy.creation_record
        del policy.mutation_record

        # Update old channel names with new channel names.
        for i, channel in enumerate(policy.notification_channels):
            new_channel = channel_name_map.get(channel)
            if new_channel:
                policy.notification_channels[i] = new_channel

        updated = False

        if is_same_project:
            try:
                alert_client.update_alert_policy(alert_policy=policy)
                updated = True
            except google.api_core.exceptions.NotFound:
                pass  # The policy was deleted.  Create it below.
            except google.api_core.exceptions.InvalidArgument:
                # Annoying that API throws InvalidArgument when the policy
                # does not exist.  Seems like it should throw NotFound.
                pass  # The policy was deleted.  Create it below.

        if not updated:
            # The policy no longer exists.  Recreate it.
            old_name = policy.name
            del policy.name
            for condition in policy.conditions:
                del condition.name
            policy = alert_client.create_alert_policy(
                name=project_name, alert_policy=policy
            )
        print("Updated", policy.name)