Remove the documentation from the code repository (moved to symfony/symfony-docs#9437)

Author: sroze

src/Symfony/Component/Message/README.md

@@ -11,253 +11,3 @@ Resources
   * [Report issues](https://github.com/symfony/symfony/issues) and
     [send Pull Requests](https://github.com/symfony/symfony/pulls)
     in the [main Symfony repository](https://github.com/symfony/symfony)
-
-
-Documentation
--------------
-
-**Note:** this documentation is to be moved to symfony.com when merging the Component.
-
-### Concepts
-
-![Component overview](Resources/doc/component-overview.png)
-
-1. **Sender**
-   Responsible for serializing and sending the message to _something_. This something can be a message broker or a 3rd 
-   party API for example.
-
-2. **Receiver**
-   Responsible for deserializing and forwarding the messages to handler(s). This can be a message queue puller or an API
-   endpoint for example.
-   
-3. **Handler**
-   Given a received message, contains the user business logic related to the message. In practice, that is just a PHP
-   callable.
-   
-
-### Bus
-
-The bus is used to dispatch messages. MessageBus' behaviour is in its ordered middleware stack. When using
-the message bus with Symfony's FrameworkBundle, the following middlewares are configured for you:
-
-1. `LoggingMiddleware` (log the processing of your messages)
-2. `SendMessageMiddleware` (enable asynchronous processing)
-3. `HandleMessageMiddleware` (call the registered handle)
-
-```php
-use App\Message\MyMessage;
-
-$result = $this->get('message_bus')->handle(new MyMessage(/* ... */));
-```
-
-### Handlers
-
-Once dispatched to the bus, messages will be handled by a "message handler". A message handler is a PHP callable 
-(i.e. a function or an instance of a class) that will do the required processing for your message. It _might_ return a
-result.
-
-```php
-namespace App\MessageHandler;
-
-use App\Message\MyMessage;
-
-class MyMessageHandler
-{
-    public function __invoke(MyMessage $message)
-    {
-        // Message processing...
-    }
-}
-```
-
-```xml
-<service id="App\Handler\MyMessageHandler">
-    <tag name="message_handler" />
-</service>
-```
-
-**Note:** If the message cannot be guessed from the handler's type-hint, use the `handles` attribute on the tag.
-
-### Asynchronous messages
-
-Using the Message Component is useful to decouple your application but it also very useful when you want to do some
-asychronous processing. This means that your application will produce a message to a queuing system and consume this
-message later in the background, using a _worker_.
-
-#### Adapters
-
-The communication with queuing system or 3rd parties is for delegated to libraries for now. You can use one of the 
-following adapters:
-
-- [PHP Enqueue bridge](https://github.com/sroze/enqueue-bridge) to use one of their 10+ compatible queues such as 
-  RabbitMq, Amazon SQS or Google Pub/Sub.
-- [Swarrot adapter](https://github.com/sroze/swarrot-bridge) to use Swarrot, a library specialised in consuming
-  messages from AMQP brokers such as RabbitMq.
-- [HTTP adapter](https://github.com/sroze/message-http-adapter) to receive and send messages through HTTP APIs.
-
-#### Routing
-
-When doing asynchronous processing, the key is to route the message to the right sender. As the routing is
-application-specific and not message-specific, the configuration can be made within the `framework.yaml` 
-configuration file as well:
-
-```yaml
-framework:
-    message:
-        routing:
-            'My\Message\MessageAboutDoingOperationalWork': my_operations_queue_sender
-```
-
-Such configuration would only route the `MessageAboutDoingOperationalWork` message to be asynchronous, the rest of the
-messages would still be directly handled.
-
-If you want to do route all the messages to a queue by default, you can use such configuration:
-```yaml
-framework:
-    message:
-        routing:
-            'My\Message\MessageAboutDoingOperationalWork': my_operations_queue_sender
-            '*': my_default_sender
-```
-
-Note that you can also route a message to multiple senders at the same time:
-```yaml
-framework:
-    message:
-        routing:
-            'My\Message\AnImportantMessage': [my_default_sender, my_audit_sender]
-```
-
-#### Same bus received and sender
-
-To allow us to receive and send messages on the same bus and prevent a loop, the message bus is equipped with the
-`WrapIntoReceivedMessage` received. It will wrap the received messages into `ReceivedMessage` objects and the 
-`SendMessageMiddleware` middleware will know it should not send these messages.
-
-### Your own sender
-
-Using the `SenderInterface`, you can easily create your own message sender. Let's say you already have an
-`ImportantAction` message going through the message bus and handled by a handler. Now, you also want to send this
-message as an email.
-
-1. Create your sender
-
-```php
-namespace App\MessageSender;
-
-use Symfony\Component\Message\SenderInterface;
-use App\Message\ImportantAction;
-
-class ImportantActionToEmailSender implements SenderInterface
-{
-    private $toEmail;
-    private $mailer;
-    
-    public function __construct(\Swift_Mailer $mailer, string $toEmail)
-    {
-        $this->mailer = $mailer;
-        $this->toEmail = $toEmail;
-    }
-    
-    public function send($message)
-    {
-        if (!$message instanceof ImportantAction) {
-            throw new \InvalidArgumentException(sprintf('Producer only supports "%s" messages.', ImportantAction::class));
-        }
-        
-        $this->mailer->send(
-            (new \Swift_Message('Important action made'))
-                ->setTo($this->toEmail)
-                ->setBody(
-                    '<h1>Important action</h1><p>Made by '.$message->getUsername().'</p>',
-                    'text/html'
-                )
-        );
-    }
-}
-```
-
-2. Register your sender service
-
-```yaml
-services:
-    App\MessageSender\ImportantActionToEmailSender:
-        arguments:
-            - "@mailer"
-            - "%to_email%"
-    
-        tags:
-            - message.sender
-```
-
-3. Route your important message to the sender
-
-```yaml
-framework:
-    message:
-        routing:
-            'App\Message\ImportantAction': [App\MessageSender\ImportantActionToEmailSender, ~]
-```
-
-**Note:** this example shows you how you can at the same time send your message and directly handle it using a `null`
-(`~`) sender.
-
-### Your own receiver
-
-A consumer is responsible of receiving messages from a source and dispatching them to the application. 
-
-Let's say you already proceed some "orders" on your application using a `NewOrder` message. Now you want to integrate with
-a 3rd party or a legacy application but you can't use an API and need to use a shared CSV file with new orders.
-
-You will read this CSV file and dispatch a `NewOrder` message. All you need to do is your custom CSV consumer and Symfony will do the rest.
-
-1. Create your receiver
-
-```php
-namespace App\MessageReceiver;
-
-use Symfony\Component\Message\ReceiverInterface;
-use Symfony\Component\Serializer\SerializerInterface;
-
-use App\Message\NewOrder;
-
-class NewOrdersFromCsvFile implements ReceiverInterface
-{
-    private $serializer;
-    private $filePath;
-    
-    public function __construct(SerializerInteface $serializer, string $filePath)
-    {
-        $this->serializer = $serializer;
-        $this->filePath = $filePath;
-    }
-    
-    public function receive() : \Generator
-    {
-        $ordersFromCsv = $this->serializer->deserialize(file_get_contents($this->filePath), 'csv'); 
-        
-        foreach ($ordersFromCsv as $orderFromCsv) {
-            yield new NewOrder($orderFromCsv['id'], $orderFromCsv['account_id'], $orderFromCsv['amount']);
-        }
-    }
-}
-```
-
-2. Register your receiver service
-
-```yaml
-services:
-    App\MessageReceiver\NewOrdersFromCsvFile:
-        arguments:
-            - "@serializer"
-            - "%new_orders_csv_file_path%"
-    
-        tags:
-            - message.receiver
-```
-
-3. Use your consumer
-
-```bash
-$ bin/console message:consume App\MessageReceived\NewOrdersFromCsvFile
-```