CommandBus.php

<?php

// ...

/**
 * Register a decorator for the command bus.
 * 
 * @param  string $decorator
 * @return CommandBus
 */
public function decorate($decorator)
{
    $this->decorators[] = $decorator;

    return $this;
}

/**
 * Execute the command
 *
 * @param  $command
 * @return mixed
 */
public function execute($command)
{
    $this->executeBusDecorators($command);

    $handler = $this->commandNameTranslator->toHandler($command);

    return $this->app->make($handler)->handle($command);
}

/**
 * Execute any provided decorators.
 *
 * @param  object $command
 * @return null
 */
protected function executeBusDecorators($command)
{
    foreach ($this->decorators as $decorator)
    {
        $this->app->make($decorator)->execute($command);
    }
}

usage.php

<?php

// This will:

- Channel the command through an input sanitizer
- Then on to a validator
- Then on to the normal processing, where it will trigger a handler to actually process the command.

$this->bus
   ->decorate('Foo\Bar\RegistrationFormSanitizer')
   ->decorate('Foo\Bar\RegistrationFormValidator')
   ->execute($registerUserCommand);