CommandNameExtractor
7 years ago
Locator
7 years ago
MethodNameInflector
7 years ago
CommandHandlerMiddleware.php
7 years ago
CommandHandlerMiddleware.php
74 lines
| 1 | <?php |
| 2 | |
| 3 | namespace League\Tactician\Handler; |
| 4 | |
| 5 | use League\Tactician\Middleware; |
| 6 | use League\Tactician\Exception\CanNotInvokeHandlerException; |
| 7 | use League\Tactician\Handler\CommandNameExtractor\CommandNameExtractor; |
| 8 | use League\Tactician\Handler\Locator\HandlerLocator; |
| 9 | use League\Tactician\Handler\MethodNameInflector\MethodNameInflector; |
| 10 | |
| 11 | /** |
| 12 | * The "core" CommandBus. Locates the appropriate handler and executes command. |
| 13 | */ |
| 14 | class CommandHandlerMiddleware implements Middleware |
| 15 | { |
| 16 | /** |
| 17 | * @var CommandNameExtractor |
| 18 | */ |
| 19 | private $commandNameExtractor; |
| 20 | |
| 21 | /** |
| 22 | * @var HandlerLocator |
| 23 | */ |
| 24 | private $handlerLocator; |
| 25 | |
| 26 | /** |
| 27 | * @var MethodNameInflector |
| 28 | */ |
| 29 | private $methodNameInflector; |
| 30 | |
| 31 | /** |
| 32 | * @param CommandNameExtractor $commandNameExtractor |
| 33 | * @param HandlerLocator $handlerLocator |
| 34 | * @param MethodNameInflector $methodNameInflector |
| 35 | */ |
| 36 | public function __construct( |
| 37 | CommandNameExtractor $commandNameExtractor, |
| 38 | HandlerLocator $handlerLocator, |
| 39 | MethodNameInflector $methodNameInflector |
| 40 | ) { |
| 41 | $this->commandNameExtractor = $commandNameExtractor; |
| 42 | $this->handlerLocator = $handlerLocator; |
| 43 | $this->methodNameInflector = $methodNameInflector; |
| 44 | } |
| 45 | |
| 46 | /** |
| 47 | * Executes a command and optionally returns a value |
| 48 | * |
| 49 | * @param object $command |
| 50 | * @param callable $next |
| 51 | * |
| 52 | * @return mixed |
| 53 | * |
| 54 | * @throws CanNotInvokeHandlerException |
| 55 | */ |
| 56 | public function execute($command, callable $next) |
| 57 | { |
| 58 | $commandName = $this->commandNameExtractor->extract($command); |
| 59 | $handler = $this->handlerLocator->getHandlerForCommand($commandName); |
| 60 | $methodName = $this->methodNameInflector->inflect($command, $handler); |
| 61 | |
| 62 | // is_callable is used here instead of method_exists, as method_exists |
| 63 | // will fail when given a handler that relies on __call. |
| 64 | if (!is_callable([$handler, $methodName])) { |
| 65 | throw CanNotInvokeHandlerException::forCommand( |
| 66 | $command, |
| 67 | "Method '{$methodName}' does not exist on handler" |
| 68 | ); |
| 69 | } |
| 70 | |
| 71 | return $handler->{$methodName}($command); |
| 72 | } |
| 73 | } |
| 74 |