http2/pipeline.php

   1 <?php
   2 // Hoplite
   3 // Copyright (c) 2016 Blue Static
   4 //
   5 // This program is free software: you can redistribute it and/or modify it
   6 // under the terms of the GNU General Public License as published by the Free
   7 // Software Foundation, either version 3 of the License, or any later version.
   8 //
   9 // This program is distributed in the hope that it will be useful, but WITHOUT
  10 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 // FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 // more details.
  13 //
  14 // You should have received a copy of the GNU General Public License along with
  15 // this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 namespace hoplite\http2;
  18
  19 require_once HOPLITE_ROOT . '/http2/middleware.php';
  20 require_once HOPLITE_ROOT . '/http2/request.php';
  21 require_once HOPLITE_ROOT . '/http2/response.php';
  22
  23 class Pipeline {
  24   private $middleware = [];
  25
  26   public function add($middleware) {
  27     /*
  28     if (!($middleware instanceof Middleware ||
  29           $middleware instanceof \Closure ||
  30           is_array($middleware))) {
  31       // TODO(php7): TypeError
  32       throw new \Exception(__FUNCTION__ . ' requires a Middleware or Closure');
  33     }
  34      */
  35     $this->middleware[] = $middleware;
  36     return $this;
  37   }
  38
  39   public function build() {
  40     $chain = new Sentinel(new NotFoundResponse());
  41     for ($i = count($this->middleware) - 1; $i >= 0; --$i) {
  42       $args = $this->middleware[$i];
  43       if ($args instanceof \Closure) {
  44         $chain = new ClosureMiddleware($this, $chain, $args);
  45       } else if (is_array($args)) {
  46         $class = array_shift($args);
  47         array_unshift($args, $this, $chain);
  48         $chain = new $class(...$args);
  49       } else {
  50         $chain = new $args($this, $chain);
  51       }
  52     }
  53
  54     return $chain;
  55   }
  56
  57   public function run(Middleware $chain) {
  58     $response = $chain->execute(new Request());
  59     $response->generate();
  60   }
  61
  62   public function buildAndRun() {
  63     $this->run($this->build());
  64   }
  65 }
  66
  67 class SubPipeline extends Middleware {
  68   public function __construct(Pipeline $subpipe) {
  69     // Skip calling super since this is a new pipeline and the
  70     // next middleware will be selected by building the subpipe.
  71     // It would be possible to build the middleware chain here, but
  72     // doing it lazily on execution is more efficient, since SubPipeline
  73     // should be used to partition applications.
  74     $this->subpipe = $subpipe;
  75   }
  76
  77   public function execute(Request $request) {
  78     return $this->subpipe->build()->execute($request);
  79   }
  80 }