Symfony 5 Messenger not auto configuring message handler - symfony

Question

I am new to Symfony framework and am trying to set up a project with Messenger (https://symfony.com/doc/current/messenger.html). My understanding is after setting up the handler class with “implements MessageHandlerInterface” the handler should be available for use but it does not seem to be working for me. I have tried several different things including setting up a new project from scratch. I am using Symfony 5.0.4.
I set up the project like this:
symfony new --full testMessenger
composer require messenger
php bin/console make:controller
Then I made a new messenger and handler and called it from the controller. Doing that I get the exception: “No handler for message "App\Message\Message".”
php bin/console debug:messenger
Output:
Messenger
=========
messenger.bus.default
---------------------
The following messages can be dispatched:
-----------------------------------------------------  
 Symfony\Component\Mailer\Messenger\SendEmailMessage   
     handled by mailer.messenger.message_handler       
 Symfony\Component\Notifier\Message\ChatMessage        
     handled by chatter.messenger.chat_handler         
 Symfony\Component\Notifier\Message\SmsMessage         
     handled by texter.messenger.sms_handler           
-----------------------------------------------------  
My code is basically the same as the samples in the message handler documentation, but I will add it here.
// src/Message.php
<?php
namespace App\Message;
class Message
{
private $content;
public function __construct(string $content)
{
$this->content = $content;
}
public function getContent(): string
{
return $this->content;
}
}
// src/MessageHandler.php
<?php
namespace App\MessageHandler;
use App\Message\Message;
use Symfony\Component\Messenger\Handler\MessageHandlerInterface;
class SmsNotificationHandler implements MessageHandlerInterface
{
public function __invoke(Message $message)
{
// ... do some work - like sending an SMS message!
}
}
// src/Controller/MessageController.php
<?php
namespace App\Controller;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\Routing\Annotation\Route;
use App\Message\Message;
class MessageController extends AbstractController
{
/**
* #Route("/message", name="message")
*/
public function index()
{
$this->dispatchMessage(new Message('Look! I created a message!'));
return $this->render('message/index.html.twig', [
'controller_name' => 'MessageController',
]);
}
}
//config/packages/messenger.yaml
framework:
messenger:
# Uncomment this (and the failed transport below) to send failed messages to this transport for later handling.
# failure_transport: failed
transports:
# https://symfony.com/doc/current/messenger.html#transport-configuration
# async: '%env(MESSENGER_TRANSPORT_DSN)%'
# failed: 'doctrine://default?queue_name=failed'
# sync: 'sync://'
routing:
# Route your messages to the transports
# 'App\Message\YourMessage': async

Answer 1

I've struggled a little with similar case, so I hope this will help someone:
So I had autowiring on and multiple buses defined like this:
final class QueryBus implements QueryBusInterface
{
use HandleTrait {
HandleTrait::handle as messengerHandle;
}
public function __construct(MessageBusInterface $messageBus)
{
$this->messageBus = $messageBus;
}
public function handle(object $query): mixed
{
return $this->messengerHandle($query);
}
}
final class CommandBus implements CommandBusInterface
{
use HandleTrait;
public function __construct(
MessageBusInterface $messageBus
) {
$this->messageBus = $messageBus;
}
public function dispatch(object $command)
{
return $this->handle($command);
}
}
// messenger.yaml
framework:
messenger:
default_bus: command_bus
buses:
command_bus: ~
query_bus: ~
And I got the same error for when dispatching a query "No handler for message..."
Eventually what helped was:
Turn off autowiring in Bus implementation directories (by excluding paths in services.yaml.
App\:
resource: '../src/'
exclude:
- '../src/Bus/'
Manually define the services:
// services.yaml
services:
_defaults:
autowire: true
autoconfigure: true
App\src\Bus\CommandBus:
arguments:
- '#command_bus'
App\src\Bus\QueryBus:
arguments:
- '#query_bus'
So actually it seems it was autowiring issue - failing to autowire 2 implementations of same Interface (the MessageBusInterface). The actual error of missing service was hiding under the messenger component.