git.stricted.de - GitHub/WoltLab/WCF.git/blob

   1 <?php
   2
   3 /**
   4  * @see       https://github.com/laminas/laminas-httphandlerrunner for the canonical source repository
   5  * @copyright https://github.com/laminas/laminas-httphandlerrunner/blob/master/COPYRIGHT.md
   6  * @license   https://github.com/laminas/laminas-httphandlerrunner/blob/master/LICENSE.md New BSD License
   7  */
   8
   9 declare(strict_types=1);
  10
  11 namespace Laminas\HttpHandlerRunner\Emitter;
  12
  13 use Laminas\HttpHandlerRunner\Exception;
  14 use Psr\Http\Message\ResponseInterface;
  15 use SplStack;
  16
  17 /**
  18  * Provides an EmitterInterface implementation that acts as a stack of Emitters.
  19  *
  20  * The implementations emit() method iterates itself.
  21  *
  22  * When iterating the stack, the first emitter to return a boolean
  23  * true value will short-circuit iteration.
  24  */
  25 class EmitterStack extends SplStack implements EmitterInterface
  26 {
  27     /**
  28      * Emit a response
  29      *
  30      * Loops through the stack, calling emit() on each; any that return a
  31      * boolean true value will short-circuit, skipping any remaining emitters
  32      * in the stack.
  33      *
  34      * As such, return a boolean false value from an emitter to indicate it
  35      * cannot emit the response, allowing the next emitter to try.
  36      */
  37     public function emit(ResponseInterface $response) : bool
  38     {
  39         foreach ($this as $emitter) {
  40             if (false !== $emitter->emit($response)) {
  41                 return true;
  42             }
  43         }
  44
  45         return false;
  46     }
  47
  48     /**
  49      * Set an emitter on the stack by index.
  50      *
  51      * @param mixed $index
  52      * @param EmitterInterface $emitter
  53      * @return void
  54      * @throws InvalidArgumentException if not an EmitterInterface instance
  55      */
  56     public function offsetSet($index, $emitter)
  57     {
  58         $this->validateEmitter($emitter);
  59         parent::offsetSet($index, $emitter);
  60     }
  61
  62     /**
  63      * Push an emitter to the stack.
  64      *
  65      * @param EmitterInterface $emitter
  66      * @return void
  67      * @throws InvalidArgumentException if not an EmitterInterface instance
  68      */
  69     public function push($emitter)
  70     {
  71         $this->validateEmitter($emitter);
  72         parent::push($emitter);
  73     }
  74
  75     /**
  76      * Unshift an emitter to the stack.
  77      *
  78      * @param EmitterInterface $emitter
  79      * @return void
  80      * @throws InvalidArgumentException if not an EmitterInterface instance
  81      */
  82     public function unshift($emitter)
  83     {
  84         $this->validateEmitter($emitter);
  85         parent::unshift($emitter);
  86     }
  87
  88     /**
  89      * Validate that an emitter implements EmitterInterface.
  90      *
  91      * @param mixed $emitter
  92      * @throws Exception\InvalidEmitterException for non-emitter instances
  93      */
  94     private function validateEmitter($emitter) : void
  95     {
  96         if (! $emitter instanceof EmitterInterface) {
  97             throw Exception\InvalidEmitterException::forEmitter($emitter);
  98         }
  99     }
 100 }