Receive notifications

Demonstrates how to convert a Pub/Sub message into a notification message

Documentation pages that include this code sample

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

Code sample

Go

import (
	"bytes"
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/pubsub"
	"github.com/golang/protobuf/jsonpb"
	securitycenterpb "google.golang.org/genproto/googleapis/cloud/securitycenter/v1"
)

func receiveMessages(w io.Writer, projectID string, subscriptionName string) error {
	// projectID := "your-project-id"
	// subsriptionName := "your-subscription-name"

	ctx := context.Background()

	client, err := pubsub.NewClient(ctx, projectID)
	if err != nil {
		return fmt.Errorf("pubsub.NewClient: %v", err)
	}
	defer client.Close()

	sub := client.Subscription(subscriptionName)
	cctx, cancel := context.WithCancel(ctx)
	err = sub.Receive(cctx, func(ctx context.Context, msg *pubsub.Message) {
		var notificationMessage = new(securitycenterpb.NotificationMessage)
		jsonpb.Unmarshal(bytes.NewReader(msg.Data), notificationMessage)

		fmt.Fprintln(w, "Got finding: ", notificationMessage.GetFinding())
		msg.Ack()
		cancel()
	})
	if err != nil {
		return fmt.Errorf("Receive: %v", err)
	}

	return nil
}

Java


import com.google.cloud.pubsub.v1.AckReplyConsumer;
import com.google.cloud.pubsub.v1.MessageReceiver;
import com.google.cloud.pubsub.v1.Subscriber;
import com.google.cloud.securitycenter.v1.NotificationMessage;
import com.google.protobuf.InvalidProtocolBufferException;
import com.google.protobuf.util.JsonFormat;
import com.google.pubsub.v1.ProjectSubscriptionName;
import com.google.pubsub.v1.PubsubMessage;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

public class NotificationReceiver {
  private NotificationReceiver() {}

  static class NotificationMessageReceiver implements MessageReceiver {

    @Override
    public void receiveMessage(PubsubMessage message, AckReplyConsumer consumer) {
      NotificationMessage.Builder notificationMessageBuilder = NotificationMessage.newBuilder();

      try {
        String jsonString = message.getData().toStringUtf8();
        JsonFormat.parser().merge(jsonString, notificationMessageBuilder);

        NotificationMessage notificationMessage = notificationMessageBuilder.build();
        System.out.println(
            String.format("Config id: %s", notificationMessage.getNotificationConfigName()));
        System.out.println(String.format("Finding: %s", notificationMessage.getFinding()));
      } catch (InvalidProtocolBufferException e) {
        System.out.println("Could not parse message: " + e);
      } finally {
        consumer.ack();
      }
    }
  }

  public static void receiveNotificationMessages(String projectId, String subscriptionId) {
    // String projectId = "{your-project}";
    // String subscriptionId = "{your-subscription}";
    ProjectSubscriptionName subscriptionName =
        ProjectSubscriptionName.of(projectId, subscriptionId);

    try {
      Subscriber subscriber =
          Subscriber.newBuilder(subscriptionName, new NotificationMessageReceiver()).build();
      subscriber.startAsync().awaitRunning();

      // This sets the timeout value of the subscriber to 10s.
      subscriber.awaitTerminated(10_000, TimeUnit.MILLISECONDS);
    } catch (IllegalStateException | TimeoutException e) {
      System.out.println("Subscriber stopped: " + e);
    }
  }
}

Node.js

const {PubSub} = require('@google-cloud/pubsub');
const {StringDecoder} = require('string_decoder');

// projectId = 'your-project-id'
// subscriptionId = 'your-subscription-id'

const subscriptionName =
  'projects/' + projectId + '/subscriptions/' + subscriptionId;
const pubSubClient = new PubSub();

function listenForMessages() {
  const subscription = pubSubClient.subscription(subscriptionName);

  // message.data is a buffer array of json
  // 1. Convert buffer to normal string
  // 2. Convert json to NotificationMessage object
  const messageHandler = message => {
    const jsonString = new StringDecoder('utf-8').write(message.data);
    const parsedNotificationMessage = JSON.parse(jsonString);

    console.log(parsedNotificationMessage);
    console.log(parsedNotificationMessage.finding);

    // ACK when done with message
    message.ack();
  };

  subscription.on('message', messageHandler);

  // Set timeout to 10 seconds
  setTimeout(() => {
    subscription.removeListener('message', messageHandler);
  }, 10000);
}

listenForMessages();

PHP

use Google\Cloud\PubSub\PubSubClient;

/** Uncomment and populate these variables in your code */
// $projectId = "{your-project-id}";
// $subscriptionId = "{your-subscription-id}";

$pubsub = new PubSubClient([
    'projectId' => $projectId,
]);
$subscription = $pubsub->subscription($subscriptionId);

foreach ($subscription->pull() as $message) {
    printf('Message: %s' . PHP_EOL, $message->data());
    // Acknowledge the Pub/Sub message has been received, so it will not be pulled multiple times.
    $subscription->acknowledge($message);
}

Python

# Requires https://cloud.google.com/pubsub/docs/quickstart-client-libraries#pubsub-client-libraries-python
import concurrent

from google.cloud import pubsub_v1
from google.cloud.securitycenter_v1 import NotificationMessage

# TODO: project_id = "your-project-id"
# TODO: subscription_name = "your-subscription-name"

def callback(message):

    # Print the data received for debugging purpose if needed
    print(f"Received message: {message.data}")

    notification_msg = NotificationMessage.from_json(message.data)

    print(
        "Notification config name: {}".format(
            notification_msg.notification_config_name
        )
    )
    print("Finding: {}".format(notification_msg.finding))

    # Ack the message to prevent it from being pulled again
    message.ack()

subscriber = pubsub_v1.SubscriberClient()
subscription_path = subscriber.subscription_path(project_id, subscription_name)

streaming_pull_future = subscriber.subscribe(subscription_path, callback=callback)

print("Listening for messages on {}...\n".format(subscription_path))
try:
    streaming_pull_future.result(timeout=1)  # Block for 1 second
except concurrent.futures.TimeoutError:
    streaming_pull_future.cancel()

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