README

This symfony messenger extension provides a transport to pull data from a HTTP source.

Installation

composer require 3slab/vdm-library-http-transport-bundle

Configuration reference

framework:
    messenger:
        transports:
            consumer:
                dsn: "http://ipconfig.io/json"
                retry_strategy:
                    max_retries: 0
                options:
                    method: GET
                    http_options: {}
                    http_executor: ~
                    monitoring:
                        enabled: true
                    retry:
                        enabled: true
                        number: 5
                        timeBeforeRetry: 5 

HTTP Executor

HTTP executor allows you to customize the behavior of the HTTP transport per transport definition inside your messenger.yaml file. Some example use cases are that the API has a pagination or needs a pre-request for authentication.

If you don't set a custom http_executor option when declaring the transport, the default DefaultHttpExecutor is used which just calls the API using the default Symfony http client with the method and http_options you have configured.

You can override this behavior in your project by providing a class that extends Vdm\Bundle\LibraryBundle\Executor\Http\AbstractHttpExecutor.

namespace App\Executor\Http;

use Psr\Log\LoggerInterface;
use Symfony\Component\Messenger\Envelope;
use Symfony\Contracts\HttpClient\HttpClientInterface;
use Vdm\Bundle\LibraryBundle\Model\Message;
use Vdm\Bundle\LibraryBundle\Stamp\StopAfterHandleStamp;

class CustomHttpExecutor extends AbstractHttpExecutor
{
    public function __construct(
        HttpClientInterface $httpClient,
        LoggerInterface $vdmLogger = null
    ) {
        parent::__construct($httpClient, $vdmLogger);
    }

    public function execute(string $dsn, string $method, array $options): iterable
    {
        // In HttpClient, request just build the request but does not execute it
        $response = $this->httpClient->request($method, $dsn, $options);

        $message = new HttpMessage($response->getContent());
        yield new Envelope($message, [new StopAfterHandleStamp()]);
    }
}

There are 2 important things your custom executor needs to do :

• yield a new envelope
• Add a StopAfterHandleStamp stamp to the yielded envelope if you want to stop after handling the last message (if not, the messenger worker may loop over and will execute it once again without stopping)

Note : thanks to the yield system, you can implement a loop in your execute function and return items once at a time

Note : you can keep state in your custom executor so if it is executed again, adapt your API call

Then references this custom executor in your transport definition in your project messenger.yaml :

framework:
    messenger:
        transports:
            api-call:
                options:
                    http_executor: App\Executor\Http\CustomHttpExecutor

Monitoring

If you enable monitoring, it will track the following metrics :

• Counter on the HTTP response status code
• Size of the HTTP response body
• The HTTP response time