Ozean12GooglePubSubBundle

A Symfony 2 / Symfony 3 bundle which integrates Google Cloud Pub Sub with your application.

Installation

1. Require the bundle:

composer require ozean12/googlepubsub

2. Set it up:

// app/AppKernel.php

public function registerBundles()
{
    $bundles = [
        // ...
        new JMS\SerializerBundle\JMSSerializerBundle(), // if not already enabled
        new Ozean12\WebTranslateItBundle\Ozean12WebTranslateItBundle(),
    ];
    
    // ...
}

# app/config/config.yml

ozean12_google_pub_sub:
  # your Google Cloud Project ID
  project_id: "%google_pub_sub_project_id%"
  
  # path to your Google Cloud Application Credentials file
  key_file_path: "%google_pub_sub_key_file_path%"
  
  # add this if you want to use logger (see Using Logger section for more info)
  logger_channel: pub_sub
  
  # list of PubSub topics (See Publishing section for more info)
  topics:
    - my_topic
    
  # list of Push subscriptions in format (subscription_name: service_name) (see Subscribing to Push messages section for more info)
  push_subscriptions:
    my_push_subscription: my_bundle.my_firts_push.subscriber

Usage

1. Publishing messages

In order to publish the message to PubSub, you need to define the topic first, as described in previous section. Once topic is defined, it can be accessed within the Publisher service:

$message = new MyTopicMessage();
$publisher = $this->container->get('ozean12_google_pubsub.publisher.my_topic');
$result = $publisher->publish($message);

MyTopicMessage is a simple class which implements the Ozean12\GooglePubSubBundle\DTO\MessageDataDTOInterface interface and holds the data which needs to be included in message.

publish method also accepts attributes array as a second argument.

If topic does not exist, it will be created automatically.

Result of the call will be an instance of Ozean12\GooglePubSubBundle\DTO\PublishMessageResultDTO which will contain the ids of created messages.

2. Subscribing to Push messages

When using the Push subscription, you need to create the endpoint which will receive the message from Google Pub/Sub and then pass it to PushSubscriberManager. This topic is outside the scope of the bundle. An example of this setup using the FOS REST Bundle:

// GoogleCloudController.php

use Ozean12\GooglePubSubBundle\DTO\PushMessageRequestDTO;

/**
 * Class GoogleCloudController
 *
 * @Version("v1")
 * @Route("/google-cloud/")
 */
class GoogleCloudController extends FOSRestController
{
    /**
     * @ApiDoc(
     *   resource = true,
     *   description = "Receive a new PubSub message and process it",
     *   statusCodes = {
     *     204 = "Returned when successful",
     *     403 = "Returned when access denied"
     *   }
     * )
     *
     * @ParamConverter("message", converter="fos_rest.request_body")
     *
     * @Route("pub-sub")
     * @Method({"POST"})
     * @View()
     *
     * @param PushMessageRequestDTO $message
     * @return mixed
     */
    public function pubSub(PushMessageRequestDTO $message)
    {
        $this->get('ozean12_google_pubsub.push_subscriber_manager.service')->processMessage($message);
    }
}

By using the @ParamConverter annotation Symfony will automatically convert the request to PushMessageRequestDTO

PushMessageRequestDTO has two properties:

• message: instance of PushMessageDTO. For all the fields refer to Push request body
• subscription: a string with the name of Pub/Sub subscription

The PushSubscriberManager->processMessage() method will iterate over all registered subscribers and run the one with the name equal to the subscription property of the message. Example of subscriber:

// MyPushSubscriber.php

use Ozean12\GooglePubSubBundle\DTO\PushMessageDTO;
use Ozean12\GooglePubSubBundle\Service\Subscriber\PushSubscriberInterface;

/**
 * Class MyPushSubscriber
 */
class MyPushSubscriber implements PushSubscriberInterface
{
    /**
     * {@inheritdoc}
     */
    public function process(PushMessageDTO $message)
    {
        /** @var SendTransactionalEmailDataDTO $emailDTO */
        $data = base64_decode($message->getData())

        // process your data here
    }
}

3. Using Logger

If you want to log the interaction with Google services, setup the logger_channel option with the channel you want to use. Ex:

monolog:
  handlers:
    # ...
    pub_sub:
      type:  stream
      path:  "%kernel.logs_dir%/pub_sub_%kernel.environment%.log"
      level: info
      channels: [pub_sub]
  channels:
    # ...
    - pub_sub
    
ozean12_google_pub_sub:
  # ...
  logger_channel: pub_sub

This will produce following log entries:

[2016-12-23 17:51:42] pub_sub.INFO: New topic my_topic created {"topic":"my_topic"} []
[2016-12-23 17:57:01] pub_sub.INFO: Message(s) 123456789 submitted to topic my_topic {"messages":"123456789","topic":"my_topic"} []
[2017-01-04 15:57:32] pub_sub.INFO: Received message : my_first_subscription[123456789]; Processed with MyBundle\Service\GooglePubSub\Subscriber\MyFirstSubscriber subscriber {"message":"123456789","subscription":"my_first_subscription","subscriberClass":"MyBundle\\Service\\GooglePubSub\\Subscriber\\MyFirstSubscriber"} []

Credits

Ozean12