[client] add docs.

makasim · makasim · commit 0f584eb1d14e · 2017-06-20T13:50:56.000+03:00
diff --git a/docs/bundle/message_processor.md b/docs/bundle/message_processor.md
@@ -5,6 +5,7 @@ Here we just show how to register a message processor service to enqueue. Let's
 
 * [Container tag](#container-tag)
 * [Topic subscriber](#topic-subscriber)
+* [Command subscriber](#command-subscriber)
 
 # Container tag
 
@@ -27,8 +28,8 @@ The tag has some additional options:
 
 # Topic subscriber
 
-There is a `TopicSubscriber` interface (like [EventSubscriberInterface](https://github.com/symfony/symfony/blob/master/src/Symfony/Component/EventDispatcher/EventSubscriberInterface.php)). 
-It allows to keep subscription login and process logic closer to each other. 
+There is a `TopicSubscriberInterface` interface (like [EventSubscriberInterface](https://github.com/symfony/symfony/blob/master/src/Symfony/Component/EventDispatcher/EventSubscriberInterface.php)). 
+It is handy to subscribe on event messages. It allows to keep subscription login and process logic closer to each other. 
 
 ```php
 <?php
@@ -67,6 +68,81 @@ class SayHelloProcessor implements PsrProcessor, TopicSubscriberInterface
 
 In the container you can just add the tag `enqueue.client.message_processor` and omit any other options:
 
+```yaml
+# src/AppBundle/Resources/services.yml
+
+services:
+  app.async.say_hello_processor:
+    class: 'AppBundle\Async\SayHelloProcessor'
+    tags:
+        - { name: 'enqueue.client.processor'}
+
+```
+
+# Command subscriber
+
+There is a `CommandSubscriberInterface` interface which allows to register a command handlers. 
+If you send a message using ProducerV2::sendCommand('aCommandName') method it will come to this processor.
+
+```php
+<?php
+namespace AppBundle\Async;
+
+use Enqueue\Client\CommandSubscriberInterface;
+use Enqueue\Psr\PsrProcessor;
+
+class SayHelloProcessor implements PsrProcessor, CommandSubscriberInterface
+{
+    public static function getSubscribedCommand()
+    {
+        return 'aCommandName';
+    }
+}
+```
+
+On the command subscriber you can also define additional settings such as queue and processor name:
+
+```php
+<?php
+use Enqueue\Client\CommandSubscriberInterface;
+use Enqueue\Psr\PsrProcessor;
+
+class SayHelloProcessor implements PsrProcessor, CommandSubscriberInterface
+{
+    public static function getSubscribedCommand()
+    {
+        return ['queueName' => 'fooQueue', 'processorName' => 'aCommandName'];
+    }
+}
+```
+
+There is a possibility to register a command processor which works exclusively on the queue (no other processors bound to it).
+In this case you can send messages without setting any message properties at all. Here's an example of such a processor:
+
+In the container you can just add the tag `enqueue.client.message_processor` and omit any other options:
+
+```php
+<?php
+use Enqueue\Client\CommandSubscriberInterface;
+use Enqueue\Psr\PsrProcessor;
+
+class SayHelloProcessor implements PsrProcessor, CommandSubscriberInterface
+{
+    public static function getSubscribedCommand()
+    {
+        return [
+           'processorName' => 'the-exclusive-command-name',
+           'queueName' => 'the-queue-name',
+           'queueNameHardcoded' => true,
+           'exclusive' => true,
+       ];
+    }
+}
+```
+
+The same as a topic subscriber you have to tag a processor service (no need to add any options there):
+
+
 ```yaml
 # src/AppBundle/Resources/services.yml
 
