Messenger provides a message bus with the ability to send messages and then handle them immediately in your application or send them through transports (e.g. queues) to be handled later. To learn more deeply about it, read the :doc:`Messenger component docs </components/messenger>`.
In applications using :ref:`Symfony Flex <symfony-flex>`, run this command to install messenger:
$ composer require symfony/messenger
Messenger centers around two different classes that you'll create: (1) a message class that holds data and (2) a handler(s) class that will be called when that message is dispatched. The handler class will read the message class and perform one or more tasks.
There are no specific requirements for a message class, except that it can be serialized:
// src/Message/SmsNotification.php
namespace App\Message;
class SmsNotification
{
private $content;
public function __construct(string $content)
{
$this->content = $content;
}
public function getContent(): string
{
return $this->content;
}
}
.. versionadded:: 5.4
The ``#[AsMessageHandler]`` PHP attribute was introduced in Symfony
5.4. PHP attributes require at least PHP 8.0.
A message handler is a PHP callable, the recommended way to create it is to
create a class that has the :class:`Symfony\\Component\\Messenger\\Attribute\\AsMessageHandler`
attribute and has an __invoke() method that's type-hinted with the
message class (or a message interface):
// src/MessageHandler/SmsNotificationHandler.php
namespace App\MessageHandler;
use App\Message\SmsNotification;
use Symfony\Component\Messenger\Attribute\AsMessageHandler;
#[AsMessageHandler]
class SmsNotificationHandler
{
public function __invoke(SmsNotification $message)
{
// ... do some work - like sending an SMS message!
}
}
Note
You can also create a class without the attribute (e.g. if you're using PHP 7.4), by implementing :class:`Symfony\\Component\\Messenger\\Handler\\MessageHandlerInterface` instead.
Thanks to :ref:`autoconfiguration <services-autoconfigure>` and the SmsNotification
type-hint, Symfony knows that this handler should be called when an SmsNotification
message is dispatched. Most of the time, this is all you need to do. But you can
also :ref:`manually configure message handlers <messenger-handler-config>`. To
see all the configured handlers, run:
$ php bin/console debug:messenger
You're ready! To dispatch the message (and call the handler), inject the
messenger.default_bus service (via the MessageBusInterface), like in a controller:
// src/Controller/DefaultController.php
namespace App\Controller;
use App\Message\SmsNotification;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\Messenger\MessageBusInterface;
class DefaultController extends AbstractController
{
public function index(MessageBusInterface $bus)
{
// will cause the SmsNotificationHandler to be called
$bus->dispatch(new SmsNotification('Look! I created a message!'));
// ...
}
}
By default, messages are handled as soon as they are dispatched. If you want to handle a message asynchronously, you can configure a transport. A transport is capable of sending messages (e.g. to a queueing system) and then :ref:`receiving them via a worker <messenger-worker>`. Messenger supports :ref:`multiple transports <messenger-transports-config>`.
Note
If you want to use a transport that's not supported, check out the Enqueue's transport, which backs services like Kafka and Google Pub/Sub.
A transport is registered using a "DSN". Thanks to Messenger's Flex recipe, your
.env file already has a few examples.
# MESSENGER_TRANSPORT_DSN=amqp://guest:guest@localhost:5672/%2f/messages
# MESSENGER_TRANSPORT_DSN=doctrine://default
# MESSENGER_TRANSPORT_DSN=redis://localhost:6379/messagesUncomment whichever transport you want (or set it in .env.local). See
:ref:`messenger-transports-config` for more details.
Next, in config/packages/messenger.yaml, let's define a transport called async
that uses this configuration:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
transports:
async: "%env(MESSENGER_TRANSPORT_DSN)%"
# or expanded to configure more options
#async:
# dsn: "%env(MESSENGER_TRANSPORT_DSN)%"
# options: []
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:transport name="async">%env(MESSENGER_TRANSPORT_DSN)%</framework:transport>
<!-- or expanded to configure more options -->
<framework:transport name="async"
dsn="%env(MESSENGER_TRANSPORT_DSN)%"
>
<option key="...">...</option>
</framework:transport>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$framework->messenger()
->transport('async')
->dsn(env('MESSENGER_TRANSPORT_DSN'))
;
$framework->messenger()
->transport('async')
->dsn(env('MESSENGER_TRANSPORT_DSN'))
->options([])
;
};
Now that you have a transport configured, instead of handling a message immediately, you can configure them to be sent to a transport:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
transports:
async: "%env(MESSENGER_TRANSPORT_DSN)%"
routing:
# async is whatever name you gave your transport above
'App\Message\SmsNotification': async
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:routing message-class="App\Message\SmsNotification">
<!-- async is whatever name you gave your transport above -->
<framework:sender service="async"/>
</framework:routing>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$framework->messenger()
// async is whatever name you gave your transport above
->routing('App\Message\SmsNotification')->senders(['async'])
;
};
Thanks to this, the App\Message\SmsNotification will be sent to the async
transport and its handler(s) will not be called immediately. Any messages not
matched under routing will still be handled immediately, i.e. synchronously.
Note
You may use '*' as the message class. This will act as a default routing
rule for any message not matched under routing. This is useful to ensure
no message is handled synchronously by default.
The only drawback is that '*' will also apply to the emails sent with the
Symfony Mailer (which uses SendEmailMessage when Messenger is available).
This could cause issues if your emails are not serializable (e.g. if they include
file attachments as PHP resources/streams).
You can also route classes by their parent class or interface. Or send messages to multiple transports:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
routing:
# route all messages that extend this example base class or interface
'App\Message\AbstractAsyncMessage': async
'App\Message\AsyncMessageInterface': async
'My\Message\ToBeSentToTwoSenders': [async, audit]
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<!-- route all messages that extend this example base class or interface -->
<framework:routing message-class="App\Message\AbstractAsyncMessage">
<framework:sender service="async"/>
</framework:routing>
<framework:routing message-class="App\Message\AsyncMessageInterface">
<framework:sender service="async"/>
</framework:routing>
<framework:routing message-class="My\Message\ToBeSentToTwoSenders">
<framework:sender service="async"/>
<framework:sender service="audit"/>
</framework:routing>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
// route all messages that extend this example base class or interface
$messenger->routing('App\Message\AbstractAsyncMessage')->senders(['async']);
$messenger->routing('App\Message\AsyncMessageInterface')->senders(['async']);
$messenger->routing('My\Message\ToBeSentToTwoSenders')->senders(['async', 'audit']);
};
Note
If you configure routing for both a child and parent class, both rules
are used. E.g. if you have an SmsNotification object that extends
from Notification, both the routing for Notification and
SmsNotification will be used.
If you need to pass a Doctrine entity in a message, it's better to pass the entity's
primary key (or whatever relevant information the handler actually needs, like email,
etc.) instead of the object (otherwise you might see errors related to the Entity Manager):
// src/Message/NewUserWelcomeEmail.php
namespace App\Message;
class NewUserWelcomeEmail
{
private $userId;
public function __construct(int $userId)
{
$this->userId = $userId;
}
public function getUserId(): int
{
return $this->userId;
}
}
Then, in your handler, you can query for a fresh object:
// src/MessageHandler/NewUserWelcomeEmailHandler.php
namespace App\MessageHandler;
use App\Message\NewUserWelcomeEmail;
use App\Repository\UserRepository;
use Symfony\Component\Messenger\Attribute\AsMessageHandler;
#[AsMessageHandler]
class NewUserWelcomeEmailHandler
{
private $userRepository;
public function __construct(UserRepository $userRepository)
{
$this->userRepository = $userRepository;
}
public function __invoke(NewUserWelcomeEmail $welcomeEmail)
{
$user = $this->userRepository->find($welcomeEmail->getUserId());
// ... send an email!
}
}
This guarantees the entity contains fresh data.
If a message doesn't :ref:`match any routing rules <messenger-routing>`, it won't
be sent to any transport and will be handled immediately. In some cases (like
when binding handlers to different transports),
it's easier or more flexible to handle this explicitly: by creating a sync
transport and "sending" messages there to be handled immediately:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
transports:
# ... other transports
sync: 'sync://'
routing:
App\Message\SmsNotification: sync
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<!-- ... other transports -->
<framework:transport name="sync" dsn="sync://"/>
<framework:routing message-class="App\Message\SmsNotification">
<framework:sender service="sync"/>
</framework:routing>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
// ... other transports
$messenger->transport('sync')->dsn('sync://');
$messenger->routing('App\Message\SmsNotification')->senders(['sync']);
};
You can also create your own transport if you need to send or receive messages from something that is not supported. See :doc:`/messenger/custom-transport`.
Once your messages have been routed, in most cases, you'll need to "consume" them.
You can do this with the messenger:consume command:
$ php bin/console messenger:consume async
# use -vv to see details about what's happening
$ php bin/console messenger:consume async -vv
The first argument is the receiver's name (or service id if you routed to a custom service). By default, the command will run forever: looking for new messages on your transport and handling them. This command is called your "worker".
Tip
To properly stop a worker, throw an instance of :class:`Symfony\\Component\\Messenger\\Exception\\StopWorkerException`.
.. versionadded:: 5.4
The :class:`Symfony\\Component\\Messenger\\Exception\\StopWorkerException`
class was introduced in Symfony 5.4.
On production, there are a few important things to think about:
- Use a Process Manager like Supervisor or systemd to keep your worker(s) running
- You'll want one or more "workers" running at all times. To do that, use a process control system like :ref:`Supervisor <messenger-supervisor>` or :ref:`systemd <messenger-systemd>`.
- Don't Let Workers Run Forever
- Some services (like Doctrine's
EntityManager) will consume more memory over time. So, instead of allowing your worker to run forever, use a flag likemessenger:consume --limit=10to tell your worker to only handle 10 messages before exiting (then the process manager will create a new process). There are also other options like--memory-limit=128Mand--time-limit=3600. - Stopping Workers That Encounter Errors
- If a worker dependency like your database server is down, or timeout is reached,
you can try to add :ref:`reconnect logic <middleware-doctrine>`, or just quit
the worker if it receives too many errors with the
--failure-limitoption of themessenger:consumecommand. - Restart Workers on Deploy
- Each time you deploy, you'll need to restart all your worker processes so
that they see the newly deployed code. To do this, run
messenger:stop-workerson deployment. This will signal to each worker that it should finish the message it's currently handling and should shut down gracefully. Then, the process manager will create new worker processes. The command uses the :ref:`app <cache-configuration-with-frameworkbundle>` cache internally - so make sure this is configured to use an adapter you like. - Use the Same Cache Between Deploys
- If your deploy strategy involves the creation of new target directories, you
should set a value for the :ref:`cache.prefix.seed <reference-cache-prefix-seed>`
configuration option in order to use the same cache namespace between deployments.
Otherwise, the
cache.apppool will use the value of thekernel.project_dirparameter as base for the namespace, which will lead to different namespaces each time a new deployment is made.
Sometimes certain types of messages should have a higher priority and be handled before others. To make this possible, you can create multiple transports and route different messages to them. For example:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
transports:
async_priority_high:
dsn: '%env(MESSENGER_TRANSPORT_DSN)%'
options:
# queue_name is specific to the doctrine transport
queue_name: high
# for AMQP send to a separate exchange then queue
#exchange:
# name: high
#queues:
# messages_high: ~
# or redis try "group"
async_priority_low:
dsn: '%env(MESSENGER_TRANSPORT_DSN)%'
options:
queue_name: low
routing:
'App\Message\SmsNotification': async_priority_low
'App\Message\NewUserWelcomeEmail': async_priority_high
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:transport name="async_priority_high" dsn="%env(MESSENGER_TRANSPORT_DSN)%">
<framework:options>
<framework:queue>
<framework:name>Queue</framework:name>
</framework:queue>
</framework:options>
</framework:transport>
<framework:transport name="async_priority_low" dsn="%env(MESSENGER_TRANSPORT_DSN)%">
<option key="queue_name">low</option>
</framework:transport>
<framework:routing message-class="App\Message\SmsNotification">
<framework:sender service="async_priority_low"/>
</framework:routing>
<framework:routing message-class="App\Message\NewUserWelcomeEmail">
<framework:sender service="async_priority_high"/>
</framework:routing>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$messenger->transport('async_priority_high')
->dsn(env('MESSENGER_TRANSPORT_DSN'))
->options(['queue_name' => 'high']);
$messenger->transport('async_priority_low')
->dsn(env('MESSENGER_TRANSPORT_DSN'))
->options(['queue_name' => 'low']);
$messenger->routing('App\Message\SmsNotification')->senders(['async_priority_low']);
$messenger->routing('App\Message\NewUserWelcomeEmail')->senders(['async_priority_high']);
};
You can then run individual workers for each transport or instruct one worker to handle messages in a priority order:
$ php bin/console messenger:consume async_priority_high async_priority_low
The worker will always first look for messages waiting on async_priority_high. If
there are none, then it will consume messages from async_priority_low.
Some transports (notably AMQP) have the concept of exchanges and queues. A Symfony transport is always bound to an exchange. By default, the worker consumes from all queues attached to the exchange of the specified transport. However, there are use cases to want a worker to only consume from specific queues.
You can limit the worker to only process messages from specific queue(s):
$ php bin/console messenger:consume my_transport --queues=fasttrack
# you can pass the --queues option more than once to process multiple queues
$ php bin/console messenger:consume my_transport --queues=fasttrack1 --queues=fasttrack2
To allow using the queues option, the receiver must implement the
:class:`Symfony\\Component\\Messenger\\Transport\\Receiver\\QueueReceiverInterface`.
.. versionadded:: 5.3
Limiting the worker to specific queues was introduced in Symfony 5.3.
Supervisor is a great tool to guarantee that your worker process(es) is
always running (even if it closes due to failure, hitting a message limit
or thanks to messenger:stop-workers). You can install it on Ubuntu, for
example, via:
$ sudo apt-get install supervisor
Supervisor configuration files typically live in a /etc/supervisor/conf.d
directory. For example, you can create a new messenger-worker.conf file
there to make sure that 2 instances of messenger:consume are running at all
times:
;/etc/supervisor/conf.d/messenger-worker.conf
[program:messenger-consume]
command=php /path/to/your/app/bin/console messenger:consume async --time-limit=3600
user=ubuntu
numprocs=2
startsecs=0
autostart=true
autorestart=true
startretries=10
process_name=%(program_name)s_%(process_num)02dChange the async argument to use the name of your transport (or transports)
and user to the Unix user on your server.
Caution!
During a deployment, something might be unavailable (e.g. the
database) causing the consumer to fail to start. In this situation,
Supervisor will try startretries number of times to restart the
command. Make sure to change this setting to avoid getting the command
in a FATAL state, which will never restart again.
Each restart, Supervisor increases the delay by 1 second. For instance, if
the value is 10, it will wait 1 sec, 2 sec, 3 sec, etc. This gives the
service a total of 55 seconds to become available again. Increase the
startretries setting to cover the maximum expected downtime.
If you use the Redis Transport, note that each worker needs a unique consumer
name to avoid the same message being handled by multiple workers. One way to
achieve this is to set an environment variable in the Supervisor configuration
file, which you can then refer to in messenger.yaml
(see the ref:Redis section <messenger-redis-transport> below):
environment=MESSENGER_CONSUMER_NAME=%(program_name)s_%(process_num)02dNext, tell Supervisor to read your config and start your workers:
$ sudo supervisorctl reread
$ sudo supervisorctl update
$ sudo supervisorctl start messenger-consume:*
# If you deploy an update of your code, don't forget to restart your workers
# to run the new code
$ sudo supervisorctl restart messenger-consume:*
See the Supervisor docs for more details.
If you install the PCNTL PHP extension in your project, workers will handle
the SIGTERM POSIX signal to finish processing their current message before
terminating.
In some cases the SIGTERM signal is sent by Supervisor itself (e.g. stopping
a Docker container having Supervisor as its entrypoint). In these cases you
need to add a stopwaitsecs key to the program configuration (with a value
of the desired grace period in seconds) in order to perform a graceful shutdown:
[program:x]
stopwaitsecs=20While Supervisor is a great tool, it has the disadvantage that you need system access to run it. Systemd has become the standard on most Linux distributions, and has a good alternative called user services.
Systemd user service configuration files typically live in a ~/.config/systemd/user
directory. For example, you can create a new messenger-worker.service file. Or a
[email protected] file if you want more instances running at the same time:
[Unit]
Description=Symfony messenger-consume %i
[Service]
ExecStart=php /path/to/your/app/bin/console messenger:consume async --time-limit=3600
Restart=always
RestartSec=30
[Install]
WantedBy=default.targetNow, tell systemd to enable and start one worker:
$ systemctl --user enable [email protected]
$ systemctl --user start [email protected]
# to enable and start 20 workers
$ systemctl --user enable messenger-worker@{1..20}.service
$ systemctl --user start messenger-worker@{1..20}.service
If you change your service config file, you need to reload the daemon:
$ systemctl --user daemon-reload
To restart all your consumers:
$ systemctl --user restart messenger-consume@*.service
The systemd user instance is only started after the first login of the particular user. Consumer often need to start on system boot instead. Enable lingering on the user to activate that behavior:
$ loginctl enable-linger <your-username>
Logs are managed by journald and can be worked with using the journalctl command:
# follow logs of consumer nr 11
$ journalctl -f --user-unit [email protected]
# follow logs of all consumers
$ journalctl -f --user-unit messenger-consume@*
# follow all logs from your user services
$ journalctl -f _UID=$UID
See the systemd docs for more details.
Note
You either need elevated privileges for the journalctl command, or add
your user to the systemd-journal group:
$ sudo usermod -a -G systemd-journal <your-username>
PHP is designed to be stateless, there are no shared resources across different requests. In HTTP context PHP cleans everything after sending the response, so you can decide to not take care of services that may leak memory.
On the other hand, workers usually sequentially process messages in long-running CLI processes, which don't finish after processing a single message. That's why you must be careful about service states to prevent information and/or memory leakage.
However, certain Symfony services, such as the Monolog
:ref:`fingers crossed handler <logging-handler-fingers_crossed>`, leak by design.
In those cases, use the reset_on_message transport option to automatically
reset the service container between two messages:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
reset_on_message: true
transports:
async:
dsn: '%env(MESSENGER_TRANSPORT_DSN)%'
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger reset-on-message="true">
<framework:transport name="async" dsn="%env(MESSENGER_TRANSPORT_DSN)%">
</framework:transport>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$messenger->resetOnMessage(true);
};
.. versionadded:: 5.4
The ``reset_on_message`` option was introduced in Symfony 5.4.
Note
reset_on_message will default to true (with no other allowed value)
in Symfony 6. To disable this behavior, execute the messenger:consume
command with the --no-reset option.
If an exception is thrown while consuming a message from a transport it will automatically be re-sent to the transport to be tried again. By default, a message will be retried 3 times before being discarded or :ref:`sent to the failure transport <messenger-failure-transport>`. Each retry will also be delayed, in case the failure was due to a temporary issue. All of this is configurable for each transport:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
transports:
async_priority_high:
dsn: '%env(MESSENGER_TRANSPORT_DSN)%'
# default configuration
retry_strategy:
max_retries: 3
# milliseconds delay
delay: 1000
# causes the delay to be higher before each retry
# e.g. 1 second delay, 2 seconds, 4 seconds
multiplier: 2
max_delay: 0
# override all of this with a service that
# implements Symfony\Component\Messenger\Retry\RetryStrategyInterface
# service: null
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:transport name="async_priority_high" dsn="%env(MESSENGER_TRANSPORT_DSN)%?queue_name=high_priority">
<framework:retry-strategy max-retries="3" delay="1000" multiplier="2" max-delay="0"/>
</framework:transport>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$messenger->transport('async_priority_high')
->dsn(env('MESSENGER_TRANSPORT_DSN'))
// default configuration
->retryStrategy()
->maxRetries(3)
// milliseconds delay
->delay(1000)
// causes the delay to be higher before each retry
// e.g. 1 second delay, 2 seconds, 4 seconds
->multiplier(2)
->maxDelay(0)
// override all of this with a service that
// implements Symfony\Component\Messenger\Retry\RetryStrategyInterface
->service(null)
;
};
Tip
Symfony triggers a :class:`Symfony\\Component\\Messenger\\Event\\WorkerMessageRetriedEvent` when a message is retried so you can run your own logic.
.. versionadded:: 5.2
The ``WorkerMessageRetriedEvent`` class was introduced in Symfony 5.2.
Sometimes handling a message might fail in a way that you know is permanent and should not be retried. If you throw :class:`Symfony\\Component\\Messenger\\Exception\\UnrecoverableMessageHandlingException`, the message will not be retried.
.. versionadded:: 5.1
The ``RecoverableMessageHandlingException`` was introduced in Symfony 5.1.
Sometimes handling a message must fail in a way that you know is temporary
and must be retried. If you throw
:class:`Symfony\\Component\\Messenger\\Exception\\RecoverableMessageHandlingException`,
the message will always be retried infinitely and max_retries setting will be ignored.
If a message fails it is retried multiple times (max_retries) and then will
be discarded. To avoid this happening, you can instead configure a failure_transport:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
# after retrying, messages will be sent to the "failed" transport
failure_transport: failed
transports:
# ... other transports
failed: 'doctrine://default?queue_name=failed'
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<!-- after retrying, messages will be sent to the "failed" transport -->
<framework:messenger failure-transport="failed">
<!-- ... other transports -->
<framework:transport name="failed" dsn="doctrine://default?queue_name=failed"/>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
// after retrying, messages will be sent to the "failed" transport
$messenger->failureTransport('failed');
// ... other transports
$messenger->transport('failed')
->dsn('doctrine://default?queue_name=failed');
};
In this example, if handling a message fails 3 times (default max_retries),
it will then be sent to the failed transport. While you can use
messenger:consume failed to consume this like a normal transport, you'll
usually want to manually view the messages in the failure transport and choose
to retry them:
# see all messages in the failure transport
$ php bin/console messenger:failed:show
# see details about a specific failure
$ php bin/console messenger:failed:show 20 -vv
# view and retry messages one-by-one
$ php bin/console messenger:failed:retry -vv
# retry specific messages
$ php bin/console messenger:failed:retry 20 30 --force
# remove a message without retrying it
$ php bin/console messenger:failed:remove 20
# remove messages without retrying them and show each message before removing it
$ php bin/console messenger:failed:remove 20 30 --show-messages
.. versionadded:: 5.1
The ``--show-messages`` option was introduced in Symfony 5.1.
If the message fails again, it will be re-sent back to the failure transport due to the normal :ref:`retry rules <messenger-retries-failures>`. Once the max retry has been hit, the message will be discarded permanently.
.. versionadded:: 5.3
The possibility to use multiple failed transports was introduced in Symfony 5.3.
Sometimes it is not enough to have a single, global failed transport configured
because some messages are more important than others. In those cases, you can
override the failure transport for only specific transports:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
# after retrying, messages will be sent to the "failed" transport
# by default if no "failed_transport" is configured inside a transport
failure_transport: failed_default
transports:
async_priority_high:
dsn: '%env(MESSENGER_TRANSPORT_DSN)%'
failure_transport: failed_high_priority
# since no failed transport is configured, the one used will be
# the global "failure_transport" set
async_priority_low:
dsn: 'doctrine://default?queue_name=async_priority_low'
failed_default: 'doctrine://default?queue_name=failed_default'
failed_high_priority: 'doctrine://default?queue_name=failed_high_priority'
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<!-- after retrying, messages will be sent to the "failed" transport
by default if no "failed-transport" is configured inside a transport -->
<framework:messenger failure-transport="failed_default">
<framework:transport name="async_priority_high" dsn="%env(MESSENGER_TRANSPORT_DSN)%" failure-transport="failed_high_priority"/>
<!-- since no "failed_transport" is configured, the one used will be
the global "failed_transport" set -->
<framework:transport name="async_priority_low" dsn="doctrine://default?queue_name=async_priority_low"/>
<framework:transport name="failed_default" dsn="doctrine://default?queue_name=failed_default"/>
<framework:transport name="failed_high_priority" dsn="doctrine://default?queue_name=failed_high_priority"/>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
// after retrying, messages will be sent to the "failed" transport
// by default if no "failure_transport" is configured inside a transport
$messenger->failureTransport('failed_default');
$messenger->transport('async_priority_high')
->dsn(env('MESSENGER_TRANSPORT_DSN'))
->failureTransport('failed_high_priority');
// since no failed transport is configured, the one used will be
// the global failure_transport set
$messenger->transport('async_priority_low')
->dsn('doctrine://default?queue_name=async_priority_low');
$messenger->transport('failed_default')
->dsn('doctrine://default?queue_name=failed_default');
$messenger->transport('failed_high_priority')
->dsn('doctrine://default?queue_name=failed_high_priority');
};
If there is no failure_transport defined globally or on the transport level,
the messages will be discarded after the number of retries.
The failed commands have an optional option --transport to specify
the failure_transport configured at the transport level.
# see all messages in "failure_transport" transport
$ php bin/console messenger:failed:show --transport=failure_transport
# retry specific messages from "failure_transport"
$ php bin/console messenger:failed:retry 20 30 --transport=failure_transport --force
# remove a message without retrying it from "failure_transport"
$ php bin/console messenger:failed:remove 20 --transport=failure_transport
Messenger supports a number of different transport types, each with their own options. Options can be passed to the transport via a DSN string or configuration.
# .env
MESSENGER_TRANSPORT_DSN=amqp://localhost/%2f/messages?auto_setup=false.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
transports:
my_transport:
dsn: "%env(MESSENGER_TRANSPORT_DSN)%"
options:
auto_setup: false
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:transport name="my_transport" dsn="%env(MESSENGER_TRANSPORT_DSN)%">
<framework:options auto-setup="false"/>
</framework:transport>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$messenger->transport('my_transport')
->dsn(env('MESSENGER_TRANSPORT_DSN'))
->options(['auto_setup' => false]);
};
Options defined under options take precedence over ones defined in the DSN.
The AMQP transport uses the AMQP PHP extension to send messages to queues like RabbitMQ.
.. versionadded:: 5.1
Starting from Symfony 5.1, the AMQP transport has moved to a separate package.
Install it by running:
.. code-block:: terminal
$ composer require symfony/amqp-messenger
The AMQP transport DSN may looks like this:
# .env
MESSENGER_TRANSPORT_DSN=amqp://guest:guest@localhost:5672/%2f/messages
# or use the AMQPS protocol
MESSENGER_TRANSPORT_DSN=amqps://guest:guest@localhost/%2f/messages.. versionadded:: 5.2
The AMQPS protocol support was introduced in Symfony 5.2.
If you want to use TLS/SSL encrypted AMQP, you must also provide a CA certificate.
Define the certificate path in the amqp.cacert PHP.ini setting
(e.g. amqp.cacert = /etc/ssl/certs) or in the cacert parameter of the
DSN (e.g amqps://localhost?cacert=/etc/ssl/certs/).
The default port used by TLS/SSL encrypted AMQP is 5671, but you can overwrite
it in the port parameter of the DSN (e.g. amqps://localhost?cacert=/etc/ssl/certs/&port=12345).
Note
By default, the transport will automatically create any exchanges, queues and
binding keys that are needed. That can be disabled, but some functionality
may not work correctly (like delayed queues).
To not autocreate any queues, you can configure a transport with queues: [].
Note
With Symfony 5.3 or newer, you can limit the consumer of an AMQP transport to only process messages from some queues of an exchange. See :ref:`messenger-limit-queues`.
The transport has a number of other options, including ways to configure the exchange, queues binding keys and more. See the documentation on :class:`Symfony\\Component\\Messenger\\Bridge\\Amqp\\Transport\\Connection`.
The transport has a number of options:
| Option | Description | Default |
|---|---|---|
auto_setup |
Whether the exchanges and queues should be created automatically during send / get. | true |
cacert |
Path to the CA cert file in PEM format. | |
cert |
Path to the client certificate in PEM format. | |
channel_max |
Specifies highest channel number that the server permits. 0 means standard extension limit | |
confirm_timeout |
Timeout in seconds for confirmation; if none specified, transport will not wait for message confirmation. Note: 0 or greater seconds. May be fractional. | |
connect_timeout |
Connection timeout. Note: 0 or greater seconds. May be fractional. | |
frame_max |
The largest frame size that the server proposes for the connection, including frame header and end-byte. 0 means standard extension limit (depends on librabbimq default frame size limit) | |
heartbeat |
The delay, in seconds, of the connection heartbeat that the server wants. 0 means the server does not want a heartbeat. Note, librabbitmq has limited heartbeat support, which means heartbeats checked only during blocking calls. | |
host |
Hostname of the AMQP service | |
key |
Path to the client key in PEM format. | |
login |
Username to use to connect the AMQP service | |
password |
Password to use to connect to the AMQP service | |
persistent |
'false' |
|
port |
Port of the AMQP service | |
prefetch_count |
||
read_timeout |
Timeout in for income activity. Note: 0 or greater seconds. May be fractional. | |
retry |
||
sasl_method |
||
verify |
Enable or disable peer verification. If peer verification is enabled then the common name in the server certificate must match the server name. Peer verification is enabled by default. | |
vhost |
Virtual Host to use with the AMQP service | |
write_timeout |
Timeout in for outcome activity. Note: 0 or greater seconds. May be fractional. | |
delay[queue_name_pattern] |
Pattern to use to create the queues | delay_%exchange_name%_%routing_key%_%delay% |
delay[exchange_name] |
Name of the exchange to be used for the delayed/retried messages | delays |
queues[name][arguments] |
Extra arguments | |
queues[name][binding_arguments] |
Arguments to be used while binding the queue. | |
queues[name][binding_keys] |
The binding keys (if any) to bind to this queue | |
queues[name][flags] |
Queue flags | AMQP_DURABLE |
exchange[arguments] |
Extra arguments for the exchange (e.g.
alternate-exchange) |
|
exchange[default_publish_routing_key] |
Routing key to use when publishing, if none is specified on the message | |
exchange[flags] |
Exchange flags | AMQP_DURABLE |
exchange[name] |
Name of the exchange | |
exchange[type] |
Type of exchange | fanout |
.. versionadded:: 5.2
The ``confirm_timeout`` option was introduced in Symfony 5.2.
.. deprecated:: 5.3
The ``prefetch_count`` option was deprecated in Symfony 5.3 because it has
no effect on the AMQP Messenger transport.
You can also configure AMQP-specific settings on your message by adding :class:`Symfony\\Component\\Messenger\\Bridge\\Amqp\\Transport\\AmqpStamp` to your Envelope:
use Symfony\Component\Messenger\Bridge\Amqp\Transport\AmqpStamp;
// ...
$attributes = [];
$bus->dispatch(new SmsNotification(), [
new AmqpStamp('custom-routing-key', AMQP_NOPARAM, $attributes),
]);
Caution!
The consumers do not show up in an admin panel as this transport does not rely on
\AmqpQueue::consume() which is blocking. Having a blocking receiver makes
the --time-limit/--memory-limit options of the messenger:consume command as well as
the messenger:stop-workers command inefficient, as they all rely on the fact that
the receiver returns immediately no matter if it finds a message or not. The consume
worker is responsible for iterating until it receives a message to handle and/or until one
of the stop conditions is reached. Thus, the worker's stop logic cannot be reached if it
is stuck in a blocking call.
The Doctrine transport can be used to store messages in a database table.
.. versionadded:: 5.1
Starting from Symfony 5.1, the Doctrine transport has moved to a separate package.
Install it by running:
.. code-block:: terminal
$ composer require symfony/doctrine-messenger
The Doctrine transport DSN may looks like this:
# .env
MESSENGER_TRANSPORT_DSN=doctrine://defaultThe format is doctrine://<connection_name>, in case you have multiple connections
and want to use one other than the "default". The transport will automatically create
a table named messenger_messages.
.. versionadded:: 5.1
The ability to automatically generate a migration for the ``messenger_messages``
table was introduced in Symfony 5.1 and DoctrineBundle 2.1.
If you want to change the default table name, pass a custom table name in the
DSN by using the table_name option:
# .env
MESSENGER_TRANSPORT_DSN=doctrine://default?table_name=your_custom_table_nameOr, to create the table yourself, set the auto_setup option to false and
:ref:`generate a migration <doctrine-creating-the-database-tables-schema>`.
Caution!
The datetime property of the messages stored in the database uses the timezone of the current system. This may cause issues if multiple machines with different timezone configuration use the same storage.
The transport has a number of options:
| Option | Description | Default |
|---|---|---|
| table_name | Name of the table | messenger_messages |
| queue_name | Name of the queue (a column in the table, to use one table for multiple transports) | default |
| redeliver_timeout | Timeout before retrying a message that's in the queue but in the "handling" state (if a worker stopped for some reason, this will occur, eventually you should retry the message) - in seconds. | 3600 |
| auto_setup | Whether the table should be created automatically during send / get. | true |
Note
Set redeliver_timeout to a greater value than your slowest message
duration. Otherwise, some messages will start a second time while the
first one is still being handled.
.. versionadded:: 5.1
The ability to leverage PostgreSQL's LISTEN/NOTIFY was introduced
in Symfony 5.1.
When using PostgreSQL, you have access to the following options to leverage the LISTEN/NOTIFY feature. This allow for a more performant approach than the default polling behavior of the Doctrine transport because PostgreSQL will directly notify the workers when a new message is inserted in the table.
| Option | Description | Default |
|---|---|---|
| use_notify | Whether to use LISTEN/NOTIFY. | true |
| check_delayed_interval | The interval to check for delayed messages, in milliseconds. Set to 0 to disable checks. | 60000 |
| get_notify_timeout | The length of time to wait for a
response when calling
PDO::pgsqlGetNotify, in milliseconds. |
0 |
.. versionadded:: 5.2
The Beanstalkd transport was introduced in Symfony 5.2.
The Beanstalkd transport sends messages directly to a Beanstalkd work queue. Install it by running:
$ composer require symfony/beanstalkd-messenger
The Beanstalkd transport DSN may looks like this:
# .env
MESSENGER_TRANSPORT_DSN=beanstalkd://localhost:11300?tube_name=foo&timeout=4&ttr=120
# If no port, it will default to 11300
MESSENGER_TRANSPORT_DSN=beanstalkd://localhostThe transport has a number of options:
| Option | Description | Default |
|---|---|---|
| tube_name | Name of the queue | default |
| timeout | Message reservation timeout - in seconds. | 0 (will cause the server to immediately return either a response or a TransportException will be thrown) |
| ttr | The message time to run before it is put back in the ready queue - in seconds. | 90 |
The Redis transport uses streams to queue messages. This transport requires the Redis PHP extension (>=4.3) and a running Redis server (^5.0).
.. versionadded:: 5.1
Starting from Symfony 5.1, the Redis transport has moved to a separate package.
Install it by running:
.. code-block:: terminal
$ composer require symfony/redis-messenger
The Redis transport DSN may looks like this:
# .env
MESSENGER_TRANSPORT_DSN=redis://localhost:6379/messages
# Full DSN Example
MESSENGER_TRANSPORT_DSN=redis://password@localhost:6379/messages/symfony/consumer?auto_setup=true&serializer=1&stream_max_entries=0&dbindex=0&delete_after_ack=true
# Redis Cluster Example
MESSENGER_TRANSPORT_DSN=redis://host-01:6379,redis://host-02:6379,redis://host-03:6379,redis://host-04:6379
# Unix Socket Example
MESSENGER_TRANSPORT_DSN=redis:///var/run/redis.sock.. versionadded:: 5.1
The Unix socket DSN was introduced in Symfony 5.1.
A number of options can be configured via the DSN or via the options key
under the transport in messenger.yaml:
| Option | Description | Default |
|---|---|---|
| stream | The Redis stream name | messages |
| group | The Redis consumer group name | symfony |
| consumer | Consumer name used in Redis | consumer |
| auto_setup | Create the Redis group automatically? | true |
| auth | The Redis password | |
| delete_after_ack | If true, messages are deleted
automatically after processing them |
false |
| delete_after_reject | If true, messages are deleted
automatically if they are rejected |
true |
| lazy | Connect only when a connection is really needed | false |
| serializer | How to serialize the final payload
in Redis (the
Redis::OPT_SERIALIZER option) |
Redis::SERIALIZER_PHP |
| stream_max_entries | The maximum number of entries which the stream will be trimmed to. Set it to a large enough number to avoid losing pending messages | 0 (which means "no trimming") |
| tls | Enable TLS support for the connection | false |
| redeliver_timeout | Timeout before retrying a pending message which is owned by an abandoned consumer (if a worker died for some reason, this will occur, eventually you should retry the message) - in seconds. | 3600 |
| claim_interval | Interval on which pending/abandoned messages should be checked for to claim - in milliseconds | 60000 (1 Minute) |
Caution!
There should never be more than one messenger:consume command running with the same
combination of stream, group and consumer, or messages could end up being
handled more than once. If you run multiple queue workers, consumer can be set to an
environment variable, like %env(MESSENGER_CONSUMER_NAME)%, set by Supervisor
(example below) or any other service used to manage the worker processes.
In a container environment, the HOSTNAME can be used as the consumer name, since
there is only one worker per container/host. If using Kubernetes to orchestrate the
containers, consider using a StatefulSet to have stable names.
Tip
Set delete_after_ack to true (if you use a single group) or define
stream_max_entries (if you can estimate how many max entries is acceptable
in your case) to avoid memory leaks. Otherwise, all messages will remain
forever in Redis.
.. versionadded:: 5.1
The ``delete_after_ack``, ``redeliver_timeout`` and ``claim_interval``
options were introduced in Symfony 5.1.
.. versionadded:: 5.2
The ``delete_after_reject`` and ``lazy`` options were introduced in Symfony 5.2.
.. deprecated:: 5.4
Not setting a explicit value for the ``delete_after_ack`` option is
deprecated since Symfony 5.4. In Symfony 6.0, the default value of this
option changes from ``false`` to ``true``.
The in-memory transport does not actually deliver messages. Instead, it
holds them in memory during the request, which can be useful for testing.
For example, if you have an async_priority_normal transport, you could
override it in the test environment to use this transport:
.. configuration-block::
.. code-block:: yaml
# config/packages/test/messenger.yaml
framework:
messenger:
transports:
async_priority_normal: 'in-memory://'
.. code-block:: xml
<!-- config/packages/test/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:transport name="async_priority_normal" dsn="in-memory://"/>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/test/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$messenger->transport('async_priority_normal')
->dsn('in-memory://');
};
Then, while testing, messages will not be delivered to the real transport. Even better, in a test, you can check that exactly one message was sent during a request:
// tests/Controller/DefaultControllerTest.php
namespace App\Tests\Controller;
use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
use Symfony\Component\Messenger\Transport\InMemoryTransport;
class DefaultControllerTest extends WebTestCase
{
public function testSomething()
{
$client = static::createClient();
// ...
$this->assertSame(200, $client->getResponse()->getStatusCode());
/* @var InMemoryTransport $transport */
$transport = $this->getContainer()->get('messenger.transport.async_priority_normal');
$this->assertCount(1, $transport->getSent());
}
}
The transport has a number of options:
serialize(boolean, default:false)- Whether to serialize messages or not. This is useful to test an additional layer, especially when you use your own message serializer.
.. versionadded:: 5.3
The ``serialize`` option was introduced in Symfony 5.3.
Note
All in-memory transports will be reset automatically after each test in
test classes extending
:class:`Symfony\\Bundle\\FrameworkBundle\\Test\\KernelTestCase`
or :class:`Symfony\\Bundle\\FrameworkBundle\\Test\\WebTestCase`.
.. versionadded:: 5.1
The Amazon SQS transport was introduced in Symfony 5.1.
The Amazon SQS transport is perfect for applications hosted on AWS. Install it by running:
$ composer require symfony/amazon-sqs-messenger
The SQS transport DSN may looks like this:
# .env
MESSENGER_TRANSPORT_DSN=https://sqs.eu-west-3.amazonaws.com/123456789012/messages?access_key=AKIAIOSFODNN7EXAMPLE&secret_key=j17M97ffSVoKI0briFoo9a
MESSENGER_TRANSPORT_DSN=sqs://localhost:9494/messages?sslmode=disableNote
The transport will automatically create queues that are needed. This
can be disabled by setting the auto_setup option to false.
Tip
Before sending or receiving a message, Symfony needs to convert the queue
name into an AWS queue URL by calling the GetQueueUrl API in AWS. This
extra API call can be avoided by providing a DSN which is the queue URL.
.. versionadded:: 5.2
The feature to provide the queue URL in the DSN was introduced in Symfony 5.2.
The transport has a number of options:
| Option | Description | Default |
|---|---|---|
access_key |
AWS access key | must be urlencoded |
account |
Identifier of the AWS account | The owner of the credentials |
auto_setup |
Whether the queue should be created automatically during send / get. | true |
buffer_size |
Number of messages to prefetch | 9 |
debug |
If true it logs all HTTP requests
and responses (it impacts performance) |
false |
endpoint |
Absolute URL to the SQS service | https://sqs.eu-west-1.amazonaws.com |
poll_timeout |
Wait for new message duration in seconds | 0.1 |
queue_name |
Name of the queue | messages |
region |
Name of the AWS region | eu-west-1 |
secret_key |
AWS secret key | must be urlencoded |
visibility_timeout |
Amount of seconds the message will not be visible (Visibility Timeout) | Queue's configuration |
wait_time |
Long polling duration in seconds | 20 |
.. versionadded:: 5.3
The ``debug`` option was introduced in Symfony 5.3.
Note
The wait_time parameter defines the maximum duration Amazon SQS should
wait until a message is available in a queue before sending a response.
It helps reducing the cost of using Amazon SQS by eliminating the number
of empty responses.
The poll_timeout parameter defines the duration the receiver should wait
before returning null. It avoids blocking other receivers from being called.
Note
If the queue name is suffixed by .fifo, AWS will create a FIFO queue.
Use the stamp :class:`Symfony\\Component\\Messenger\\Bridge\\AmazonSqs\\Transport\\AmazonSqsFifoStamp`
to define the Message group ID and the Message deduplication ID.
FIFO queues don't support setting a delay per message, a value of delay: 0
is required in the retry strategy settings.
When messages are sent to (and received from) a transport, they're serialized
using PHP's native serialize() & unserialize() functions. You can change
this globally (or for each transport) to a service that implements
:class:`Symfony\\Component\\Messenger\\Transport\\Serialization\\SerializerInterface`:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
serializer:
default_serializer: messenger.transport.symfony_serializer
symfony_serializer:
format: json
context: { }
transports:
async_priority_normal:
dsn: # ...
serializer: messenger.transport.symfony_serializer
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:serializer default-serializer="messenger.transport.symfony_serializer">
<framework:symfony-serializer format="json">
<framework:context/>
</framework:symfony-serializer>
</framework:serializer>
<framework:transport name="async_priority_normal" dsn="..." serializer="messenger.transport.symfony_serializer"/>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$messenger->serializer()
->defaultSerializer('messenger.transport.symfony_serializer')
->symfonySerializer()
->format('json')
->context('foo', 'bar');
$messenger->transport('async_priority_normal')
->dsn('...')
->serializer('messenger.transport.symfony_serializer');
};
The messenger.transport.symfony_serializer is a built-in service that uses
the :doc:`Serializer component </serializer>` and can be configured in a few ways.
If you do choose to use the Symfony serializer, you can control the context
on a case-by-case basis via the :class:`Symfony\\Component\\Messenger\\Stamp\\SerializerStamp`
(see Envelopes & Stamps).
Tip
When sending/receiving messages to/from another application, you may need more control over the serialization process. Using a custom serializer provides that control. See SymfonyCasts' message serializer tutorial for details.
.. versionadded:: 5.4
The ``#[AsMessageHandler]`` PHP attribute was introduced in Symfony
5.4. PHP attributes require at least PHP 8.0.
You can configure your handler by passing options to the attribute:
// src/MessageHandler/SmsNotificationHandler.php
namespace App\MessageHandler;
use App\Message\OtherSmsNotification;
use App\Message\SmsNotification;
use Symfony\Component\Messenger\Attribute\AsMessageHandler;
#[AsMessageHandler(fromTransport: 'async', priority: 10)]
class SmsNotificationHandler
{
public function __invoke(SmsNotification $message)
{
// ...
}
}
Possible options to configure with the attribute are:
busfromTransporthandlesmethodpriority
Symfony will normally :ref:`find and register your handler automatically <messenger-handler>`.
But, you can also configure a handler manually - and pass it some extra config -
by tagging the handler service with messenger.message_handler
.. configuration-block::
.. code-block:: yaml
# config/services.yaml
services:
App\MessageHandler\SmsNotificationHandler:
tags: [messenger.message_handler]
# or configure with options
tags:
-
name: messenger.message_handler
# only needed if can't be guessed by type-hint
handles: App\Message\SmsNotification
.. code-block:: xml
<!-- config/services.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd">
<services>
<service id="App\MessageHandler\SmsNotificationHandler">
<!-- handles is only needed if it can't be guessed by type-hint -->
<tag name="messenger.message_handler"
handles="App\Message\SmsNotification"/>
</service>
</services>
</container>
.. code-block:: php
// config/services.php
use App\Message\SmsNotification;
use App\MessageHandler\SmsNotificationHandler;
$container->register(SmsNotificationHandler::class)
->addTag('messenger.message_handler', [
// only needed if can't be guessed by type-hint
'handles' => SmsNotification::class,
]);
Possible options to configure with tags are:
busfrom_transporthandlesmethodpriority
A handler class can handle multiple messages or configure itself by implementing :class:`Symfony\\Component\\Messenger\\Handler\\MessageSubscriberInterface`:
// src/MessageHandler/SmsNotificationHandler.php
namespace App\MessageHandler;
use App\Message\OtherSmsNotification;
use App\Message\SmsNotification;
use Symfony\Component\Messenger\Handler\MessageSubscriberInterface;
class SmsNotificationHandler implements MessageSubscriberInterface
{
public function __invoke(SmsNotification $message)
{
// ...
}
public function handleOtherSmsNotification(OtherSmsNotification $message)
{
// ...
}
public static function getHandledMessages(): iterable
{
// handle this message on __invoke
yield SmsNotification::class;
// also handle this message on handleOtherSmsNotification
yield OtherSmsNotification::class => [
'method' => 'handleOtherSmsNotification',
//'priority' => 0,
//'bus' => 'messenger.bus.default',
];
}
}
Each message can have multiple handlers, and when a message is consumed all of its handlers are called. But you can also configure a handler to only be called when it's received from a specific transport. This allows you to have a single message where each handler is called by a different "worker" that's consuming a different transport.
Suppose you have an UploadedImage message with two handlers:
ThumbnailUploadedImageHandler: you want this to be handled by a transport calledimage_transportNotifyAboutNewUploadedImageHandler: you want this to be handled by a transport calledasync_priority_normal
To do this, add the from_transport option to each handler. For example:
// src/MessageHandler/ThumbnailUploadedImageHandler.php
namespace App\MessageHandler;
use App\Message\UploadedImage;
use Symfony\Component\Messenger\Handler\MessageSubscriberInterface;
class ThumbnailUploadedImageHandler implements MessageSubscriberInterface
{
public function __invoke(UploadedImage $uploadedImage)
{
// do some thumbnailing
}
public static function getHandledMessages(): iterable
{
yield UploadedImage::class => [
'from_transport' => 'image_transport',
];
}
}
And similarly:
// src/MessageHandler/NotifyAboutNewUploadedImageHandler.php
// ...
class NotifyAboutNewUploadedImageHandler implements MessageSubscriberInterface
{
// ...
public static function getHandledMessages(): iterable
{
yield UploadedImage::class => [
'from_transport' => 'async_priority_normal',
];
}
}
Then, make sure to "route" your message to both transports:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
transports:
async_priority_normal: # ...
image_transport: # ...
routing:
# ...
'App\Message\UploadedImage': [image_transport, async_priority_normal]
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:transport name="async_priority_normal" dsn="..."/>
<framework:transport name="image_transport" dsn="..."/>
<framework:routing message-class="App\Message\UploadedImage">
<framework:sender service="image_transport"/>
<framework:sender service="async_priority_normal"/>
</framework:routing>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$messenger->transport('async_priority_normal')->dsn('...');
$messenger->transport('image_transport')->dsn('...');
$messenger->routing('App\Message\UploadedImage')
->senders(['image_transport', 'async_priority_normal']);
};
That's it! You can now consume each transport:
# will only call ThumbnailUploadedImageHandler when handling the message
$ php bin/console messenger:consume image_transport -vv
$ php bin/console messenger:consume async_priority_normal -vv
Caution!
If a handler does not have from_transport config, it will be executed
on every transport that the message is received from.
You can declare "special" handlers which will process messages by batch. By doing so, the handler will wait for a certain amount of messages to be pending before processing them. The declaration of a batch handler is done by implementing :class:`Symfony\\Component\\Messenger\\Handler\\BatchHandlerInterface`. The :class:`Symfony\\Component\\Messenger\\Handler\\BatchHandlerTrait` is also provided in order to ease the declaration of these special handlers:
use Symfony\Component\Messenger\Handler\Acknowledger;
use Symfony\Component\Messenger\Handler\BatchHandlerInterface;
use Symfony\Component\Messenger\Handler\BatchHandlerTrait;
class MyBatchHandler implements BatchHandlerInterface
{
use BatchHandlerTrait;
public function __invoke(MyMessage $message, Acknowledger $ack = null)
{
return $this->handle($message, $ack);
}
private function process(array $jobs): void
{
foreach ($jobs as [$message, $ack]) {
try {
// Compute $result from $message...
// Acknowledge the processing of the message
$ack->ack($result);
} catch (\Throwable $e) {
$ack->nack($e);
}
}
}
// Optionally, you can redefine the `shouldFlush()` method
// of the trait to define your own batch size
private function shouldFlush(): bool
{
return 100 <= \count($this->jobs);
}
}
Note
When the $ack argument of __invoke() is null, the message is
expected to be handled synchronously. Otherwise, __invoke() is
expected to return the number of pending messages. The
:class:`Symfony\\Component\\Messenger\\Handler\\BatchHandlerTrait` handles
this for you.
Note
By default, pending batches are flushed when the worker is idle as well as when it is stopped.
.. versionadded:: 5.4
:class:`Symfony\\Component\\Messenger\\Handler\\BatchHandlerInterface` and
:class:`Symfony\\Component\\Messenger\\Handler\\BatchHandlerTrait` were
introduced in Symfony 5.4.
A message can be any PHP object. Sometimes, you may need to configure something extra about the message - like the way it should be handled inside AMQP or adding a delay before the message should be handled. You can do that by adding a "stamp" to your message:
use Symfony\Component\Messenger\Envelope;
use Symfony\Component\Messenger\MessageBusInterface;
use Symfony\Component\Messenger\Stamp\DelayStamp;
public function index(MessageBusInterface $bus)
{
$bus->dispatch(new SmsNotification('...'), [
// wait 5 seconds before processing
new DelayStamp(5000),
]);
// or explicitly create an Envelope
$bus->dispatch(new Envelope(new SmsNotification('...'), [
new DelayStamp(5000),
]));
// ...
}
Internally, each message is wrapped in an Envelope, which holds the message
and stamps. You can create this manually or allow the message bus to do it. There
are a variety of different stamps for different purposes and they're used internally
to track information about a message - like the message bus that's handling it
or if it's being retried after failure.
What happens when you dispatch a message to a message bus depends on its collection of middleware and their order. By default, the middleware configured for each bus looks like this:
add_bus_name_stamp_middleware- adds a stamp to record which bus this message was dispatched into;dispatch_after_current_bus- see :doc:`/messenger/dispatch_after_current_bus`;failed_message_processing_middleware- processes messages that are being retried via the :ref:`failure transport <messenger-failure-transport>` to make them properly function as if they were being received from their original transport;- Your own collection of middleware;
send_message- if routing is configured for the transport, this sends messages to that transport and stops the middleware chain;handle_message- calls the message handler(s) for the given message.
Note
These middleware names are actually shortcut names. The real service ids
are prefixed with messenger.middleware. (e.g. messenger.middleware.handle_message).
The middleware are executed when the message is dispatched but also again when a message is received via the worker (for messages that were sent to a transport to be handled asynchronously). Keep this in mind if you create your own middleware.
You can add your own middleware to this list, or completely disable the default middleware and only include your own.
If a middleware service is abstract, you can configure its constructor's arguments and a different instance will be created per bus.
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
buses:
messenger.bus.default:
# disable the default middleware
default_middleware: false
middleware:
# use and configure parts of the default middleware you want
- 'add_bus_name_stamp_middleware': ['messenger.bus.default']
# add your own services that implement Symfony\Component\Messenger\Middleware\MiddlewareInterface
- 'App\Middleware\MyMiddleware'
- 'App\Middleware\AnotherMiddleware'
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<!-- default-middleware: disable the default middleware -->
<framework:bus name="messenger.bus.default" default-middleware="false">
<!-- use and configure parts of the default middleware you want -->
<framework:middleware id="add_bus_name_stamp_middleware">
<framework:argument>messenger.bus.default</framework:argument>
</framework:middleware>
<!-- add your own services that implement Symfony\Component\Messenger\Middleware\MiddlewareInterface -->
<framework:middleware id="App\Middleware\MyMiddleware"/>
<framework:middleware id="App\Middleware\AnotherMiddleware"/>
</framework:bus>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$bus = $messenger->bus('messenger.bus.default')
->defaultMiddleware(false); // disable the default middleware
// use and configure parts of the default middleware you want
$bus->middleware()->id('add_bus_name_stamp_middleware')->arguments(['messenger.bus.default']);
// add your own services that implement Symfony\Component\Messenger\Middleware\MiddlewareInterface
$bus->middleware()->id('App\Middleware\MyMiddleware');
$bus->middleware()->id('App\Middleware\AnotherMiddleware');
};
If you use Doctrine in your app, a number of optional middleware exist that you may want to use:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
buses:
command_bus:
middleware:
# each time a message is handled, the Doctrine connection
# is "pinged" and reconnected if it's closed. Useful
# if your workers run for a long time and the database
# connection is sometimes lost
- doctrine_ping_connection
# After handling, the Doctrine connection is closed,
# which can free up database connections in a worker,
# instead of keeping them open forever
- doctrine_close_connection
# wraps all handlers in a single Doctrine transaction
# handlers do not need to call flush() and an error
# in any handler will cause a rollback
- doctrine_transaction
# logs an error when a Doctrine transaction was opened but not closed
- doctrine_open_transaction_logger
# or pass a different entity manager to any
#- doctrine_transaction: ['custom']
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:bus name="command_bus">
<framework:middleware id="doctrine_transaction"/>
<framework:middleware id="doctrine_ping_connection"/>
<framework:middleware id="doctrine_close_connection"/>
<framework:middleware id="doctrine_open_transaction_logger"/>
<!-- or pass a different entity manager to any -->
<!--
<framework:middleware id="doctrine_transaction">
<framework:argument>custom</framework:argument>
</framework:middleware>
-->
</framework:bus>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$bus = $messenger->bus('command_bus');
$bus->middleware()->id('doctrine_transaction');
$bus->middleware()->id('doctrine_ping_connection');
$bus->middleware()->id('doctrine_close_connection');
$bus->middleware()->id('doctrine_open_transaction_logger');
// Using another entity manager
$bus->middleware()->id('doctrine_transaction')
->arguments(['custom']);
};
.. versionadded:: 5.4
The ``doctrine_open_transaction_logger`` middleware was introduced in Symfony 5.4.
.. versionadded:: 5.3
The ``router_context`` middleware was introduced in Symfony 5.3.
Add the router_context middleware if you need to generate absolute URLs in
the consumer (e.g. render a template with links). This middleware stores the
original request context (i.e. the host, the HTTP port, etc.) which is needed
when building absolute URLs.
Add the validation middleware if you need to validate the message
object using the :doc:`Validator component </components/validator>` before handling it.
If validation fails, a ValidationFailedException will be thrown. The
:class:`Symfony\\Component\\Messenger\\Stamp\\ValidationStamp` can be used
to configure the validation groups.
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
buses:
command_bus:
middleware:
- router_context
- validation
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:bus name="command_bus">
<framework:middleware id="router_context"/>
<framework:middleware id="validation"/>
</framework:bus>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework) {
$messenger = $framework->messenger();
$bus = $messenger->bus('command_bus');
$bus->middleware()->id('router_context');
$bus->middleware()->id('validation');
};
In addition to middleware, Messenger also dispatches several events. You can :doc:`create an event listener </event_dispatcher>` to hook into various parts of the process. For each, the event class is the event name:
- :class:`Symfony\\Component\\Messenger\\Event\\SendMessageToTransportsEvent`
- :class:`Symfony\\Component\\Messenger\\Event\\WorkerMessageFailedEvent`
- :class:`Symfony\\Component\\Messenger\\Event\\WorkerMessageHandledEvent`
- :class:`Symfony\\Component\\Messenger\\Event\\WorkerMessageReceivedEvent`
- :class:`Symfony\\Component\\Messenger\\Event\\WorkerMessageRetriedEvent`
- :class:`Symfony\\Component\\Messenger\\Event\\WorkerRunningEvent`
- :class:`Symfony\\Component\\Messenger\\Event\\WorkerStartedEvent`
- :class:`Symfony\\Component\\Messenger\\Event\\WorkerStoppedEvent`
If you receive messages from other applications, it's possible that they are not
exactly in the format you need. Not all applications will return a JSON message
with body and headers fields. In those cases, you'll need to create a
new message serializer implementing the
:class:`Symfony\\Component\\Messenger\\Transport\\Serialization\\SerializerInterface`.
Let's say you want to create a message decoder:
namespace App\Messenger\Serializer;
use Symfony\Component\Messenger\Envelope;
use Symfony\Component\Messenger\Transport\Serialization\SerializerInterface;
class MessageWithTokenDecoder implements SerializerInterface
{
public function decode(array $encodedEnvelope): Envelope
{
$envelope = \json_decode($encodedEnvelope, true);
try {
// parse the data you received with your custom fields
$data = $envelope['data'];
$data['token'] = $envelope['token'];
// other operations like getting information from stamps
} catch (\Throwable $throwable) {
// wrap any exception that may occur in the envelope to send it to the failure transport
return new Envelope($throwable);
}
return new Envelope($data);
}
public function encode(Envelope $envelope): array
{
// this decoder does not encode messages, but you can implement it by returning
// an array with serialized stamps if you need to send messages in a custom format
throw new \LogicException('This serializer is only used for decoding messages.');
}
}
The next step is to tell Symfony to use this serializer in one or more of your transports:
.. configuration-block::
.. code-block:: yaml
# config/packages/messenger.yaml
framework:
messenger:
transports:
my_transport:
dsn: '%env(MY_TRANSPORT_DSN)%'
serializer: 'App\Messenger\Serializer\MessageWithTokenDecoder'
.. code-block:: xml
<!-- config/packages/messenger.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:framework="http://symfony.com/schema/dic/symfony"
xsi:schemaLocation="http://symfony.com/schema/dic/services
https://symfony.com/schema/dic/services/services-1.0.xsd
http://symfony.com/schema/dic/symfony
https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
<framework:config>
<framework:messenger>
<framework:transport name="my_transport" dsn="%env(MY_TRANSPORT_DSN)%" serializer="App\Messenger\Serializer\MessageWithTokenDecoder">
<!-- ... -->
</framework:transport>
</framework:messenger>
</framework:config>
</container>
.. code-block:: php
// config/packages/messenger.php
use App\Messenger\Serializer\MessageWithTokenDecoder;
use Symfony\Config\FrameworkConfig;
return static function (FrameworkConfig $framework): void {
$messenger = $framework->messenger();
$messenger->transport('my_transport')
->dsn('%env(MY_TRANSPORT_DSN)%')
->serializer(MessageWithTokenDecoder::class);
};
Messenger gives you a single message bus service by default. But, you can configure as many as you want, creating "command", "query" or "event" buses and controlling their middleware. See :doc:`/messenger/multiple_buses`.
.. toctree::
:maxdepth: 1
:glob:
/messenger/*