Restore policies

Demonstrates how to restore alerting policies.

Documentation pages that include this code sample

To view the code sample used in context, see the following documentation:

Code sample

C#

        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)
            {
                string policyName = policy.Name;
                // These two fields cannot be set directly, so clear them.
                policy.CreationRecord = null;
                policy.MutationRecord = null;
                // Update channel names if the channel was recreated with
                // another name.
                for (int i = 0; i < policy.NotificationChannels.Count; ++i)
                {
                    if (channelNameMap.ContainsKey(policy.NotificationChannels[i]))
                    {
                        policy.NotificationChannels[i] =
                            channelNameMap[policy.NotificationChannels[i]];
                    }
                }
                try
                {
                    Console.WriteLine("Updating policy.\n{0}",
                        policy.DisplayName);
                    bool updated = false;
                    if (isSameProject)
                        try
                        {
                            policyClient.UpdateAlertPolicy(null, policy);
                            updated = true;
                        }
                        catch (Grpc.Core.RpcException e)
                        when (e.Status.StatusCode == StatusCode.NotFound)
                        { }
                    if (!updated)
                    {
                        // The policy no longer exists.  Recreate it.
                        policy.Name = null;
                        foreach (var condition in policy.Conditions)
                        {
                            condition.Name = null;
                        }
                        policyClient.CreateAlertPolicy(projectName, policy);
                    }
                    Console.WriteLine("Restored {0}.", policyName);
                }
                catch (Exception e)
                {
                    // If one failed, continue trying to update the others.
                    exceptions.Add(e);
                }
            }
            if (exceptions.Count > 0)
            {
                throw new AggregateException(exceptions);
            }
        }

        class BackupRecord
        {
            public string ProjectId { get; set; }
            public IEnumerable<AlertPolicy> Policies { get; set; }
            public IEnumerable<NotificationChannel> Channels { get; set; }
        }

        /// <summary>
        /// Lets Newtonsoft.Json and Protobuf's json converters play nicely
        /// together.  The default Netwtonsoft.Json Deserialize method will
        /// not correctly deserialize proto messages.
        /// </summary>
        class ProtoMessageConverter : JsonConverter
        {
            public override bool CanConvert(System.Type objectType)
            {
                return typeof(Google.Protobuf.IMessage)
                    .IsAssignableFrom(objectType);
            }

            public override object ReadJson(JsonReader reader,
                System.Type objectType, object existingValue,
                JsonSerializer serializer)
            {
                // Read an entire object from the reader.
                var converter = new ExpandoObjectConverter();
                object o = converter.ReadJson(reader, objectType, existingValue,
                    serializer);
                // Convert it back to json text.
                string text = JsonConvert.SerializeObject(o);
                // And let protobuf's parser parse the text.
                IMessage message = (IMessage)Activator
                    .CreateInstance(objectType);
                return Google.Protobuf.JsonParser.Default.Parse(text,
                    message.Descriptor);
            }

            public override void WriteJson(JsonWriter writer, object value,
                JsonSerializer serializer)
            {
                writer.WriteRawValue(Google.Protobuf.JsonFormatter.Default
                    .Format((IMessage)value));
            }
        }

Go


// 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
}

Java

private static void restorePolicies(String projectId, String filePath) throws IOException {
  FileReader reader = new FileReader(filePath);
  BufferedReader bufferedReader = new BufferedReader(reader);

  JsonObject backupContent = getPolicyJsonContents(filePath, bufferedReader);
  String backupProjectId = backupContent.get("project_id").getAsString();
  boolean isSameProject = projectId.equals(backupProjectId);

  AlertPolicy[] policies = gson.fromJson(backupContent.get("policies"), AlertPolicy[].class);
  List<NotificationChannel> notificationChannels = readNotificationChannelsJson(backupContent);
  Map<String, String> restoredChannelIds =
      restoreNotificationChannels(projectId, notificationChannels, isSameProject);
  List<AlertPolicy> policiesToRestore =
      reviseRestoredPolicies(policies, isSameProject, restoredChannelIds);

  restoreRevisedPolicies(projectId, isSameProject, policiesToRestore);
}

private static List<AlertPolicy> reviseRestoredPolicies(
    AlertPolicy[] policies, boolean isSameProject, Map<String, String> restoredChannelIds) {
  List<AlertPolicy> newPolicies = Lists.newArrayListWithCapacity(policies.length);
  for (AlertPolicy policy : policies) {
    AlertPolicy.Builder policyBuilder =
        policy
            .toBuilder()
            .clearNotificationChannels()
            .clearMutationRecord()
            .clearCreationRecord();
    // Update restored notification channel names.
    for (String channelName : policy.getNotificationChannelsList()) {
      String newChannelName = restoredChannelIds.get(channelName);
      if (!Strings.isNullOrEmpty(newChannelName)) {
        policyBuilder.addNotificationChannels(newChannelName);
      }
    }
    if (!isSameProject) {
      policyBuilder.clearName();
      policyBuilder.clearConditions();
      for (AlertPolicy.Condition condition : policy.getConditionsList()) {
        policyBuilder.addConditions(condition.toBuilder().clearName());
      }
    }
    newPolicies.add(policyBuilder.build());
  }
  return newPolicies;
}

private static void restoreRevisedPolicies(
    String projectId, boolean isSameProject, List<AlertPolicy> policies) throws IOException {
  try (AlertPolicyServiceClient client = AlertPolicyServiceClient.create()) {
    for (AlertPolicy policy : policies) {
      if (!isSameProject) {
        policy = client.createAlertPolicy(ProjectName.of(projectId), policy);
      } else {
        try {
          client.updateAlertPolicy(null, policy);
        } catch (Exception e) {
          policy =
              client.createAlertPolicy(
                  ProjectName.of(projectId), policy.toBuilder().clearName().build());
        }
      }
      System.out.println(String.format("Restored %s", policy.getName()));
    }
  }
}

private static List<NotificationChannel> readNotificationChannelsJson(JsonObject backupContent) {
  if (backupContent.has("notification_channels")) {
    NotificationChannel[] channels =
        gson.fromJson(backupContent.get("notification_channels"), NotificationChannel[].class);
    return Lists.newArrayList(channels);
  }
  return Lists.newArrayList();
}

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;
}

private static JsonObject getPolicyJsonContents(String filePath, BufferedReader content) {
  try {
    return gson.fromJson(content, JsonObject.class);
  } catch (JsonSyntaxException jse) {
    throw new RuntimeException(String.format("Could not parse policies file %s", filePath), jse);
  }
}

Node.js

const fs = require('fs');

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

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

async function restorePolicies() {
  // Note: The policies are restored one at a time due to limitations in
  // the API. Otherwise, you may receive a 'service unavailable'  error
  // while trying to create multiple alerts simultaneously.

  /**
   * TODO(developer): Uncomment the following lines before running the sample.
   */
  // const projectId = 'YOUR_PROJECT_ID';

  console.log('Loading policies from ./policies_backup.json');
  const fileContent = fs.readFileSync('./policies_backup.json', 'utf-8');
  const policies = JSON.parse(fileContent);

  for (const index in policies) {
    // Restore each policy one at a time
    let policy = policies[index];
    if (await doesAlertPolicyExist(policy.name)) {
      policy = await client.updateAlertPolicy({
        alertPolicy: policy,
      });
    } else {
      // Clear away output-only fields
      delete policy.name;
      delete policy.creationRecord;
      delete policy.mutationRecord;
      policy.conditions.forEach(condition => delete condition.name);

      policy = await client.createAlertPolicy({
        name: client.projectPath(projectId),
        alertPolicy: policy,
      });
    }

    console.log(`Restored ${policy[0].name}.`);
  }
  async function doesAlertPolicyExist(name) {
    try {
      const [policy] = await client.getAlertPolicy({
        name,
      });
      return policy ? true : false;
    } catch (err) {
      if (err && err.code === 5) {
        // Error code 5 comes from the google.rpc.code.NOT_FOUND protobuf
        return false;
      }
      throw err;
    }
  }
}
restorePolicies();

PHP

use Google\Cloud\Monitoring\V3\AlertPolicyServiceClient;
use Google\Cloud\Monitoring\V3\NotificationChannelServiceClient;
use Google\Cloud\Monitoring\V3\AlertPolicy;
use Google\Cloud\Monitoring\V3\NotificationChannel;
use Google\Cloud\Monitoring\V3\NotificationChannel\VerificationStatus;
use Google\ApiCore\ApiException;

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

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

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

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

    # Convert dicts to NotificationChannels
    $channels = [];
    foreach (array_filter($record['channels']) as $channelArray) {
        $channel = new NotificationChannel();
        $channel->mergeFromJsonString(json_encode($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 {
                $channelClient->updateNotificationChannel($channel);
                $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('');
            $newChannel = $channelClient->createNotificationChannel(
                $projectName,
                $channel
            );
            $channelNameMap[$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->setCreationRecord(null);
        $policy->setMutationRecord(null);

        $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 {
                $alertClient->updateAlertPolicy($policy);
                $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('');
            }
            $policy = $alertClient->createAlertPolicy($projectName, $policy);
        }
        printf('Updated %s' . PHP_EOL, $policy->getName());
    }
    print('Restored alert policies and notification channels from backup.json.');
}

Python

def restore(project_name, backup_filename):
    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)

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