git.m6w6.name Git - m6w6/seekat/blob - lib/API/Call/Cache/Control.php

   1 <?php
   2
   3 namespace seekat\API\Call\Cache;
   4
   5 use http\Client\Request;
   6 use http\Client\Response;
   7 use http\Header;
   8 use http\Params;
   9 use http\QueryString;
  10 use http\Url;
  11
  12 final class Control {
  13         /**
  14          * @var string
  15          */
  16         private $key;
  17
  18         /**
  19          * @param Request $request
  20          */
  21         function __construct(Request $request) {
  22                 $method = $request->getRequestMethod();
  23                 switch ($method) {
  24                         case "HEAD":
  25                         case "GET":
  26                                 $uid = $this->extractAuth($request);
  27                                 $url = $request->getRequestUrl();
  28                                 $this->key = "seekat call $uid $method $url";
  29                                 break;
  30                         default:
  31                                 $this->key = "";
  32                                 break;
  33                 }
  34         }
  35
  36         /**
  37          * @return bool
  38          */
  39         public function isValid() : bool {
  40                 return strlen($this->key) > 0;
  41         }
  42
  43         /**
  44          * @return string
  45          */
  46         public function getKey() : string {
  47                 return $this->key;
  48         }
  49
  50         /**
  51          * @param Response $response
  52          * @return bool
  53          */
  54         public function isStale(Response $response) : bool {
  55                 if (false === $response->getHeader("Cache-Control") &&
  56                         false === $response->getHeader("Expires")) {
  57                         return false;
  58                 }
  59
  60                 $max_age = $this->extractMaxAge($response);
  61                 $cur_age = time() - $response->getHeader("X-Cache-Time");
  62
  63                 return $max_age >= 0 && $max_age < $cur_age;
  64         }
  65
  66         /**
  67          * @param Response $response
  68          * @return int
  69          */
  70         private function extractMaxAge(Response $response) : int {
  71                 /* @var Header $date
  72                  * @var Header $control
  73                  * @var Header $expires
  74                  */
  75                 $control = $response->getHeader("Cache-Control", Header::class);
  76                 if ($control) {
  77                         /* @var Params $params */
  78                         $params = $control->getParams();
  79                         if (isset($params["max-age"])) {
  80                                 return (int) $params->params["max-age"]["value"];
  81                         }
  82                 }
  83
  84                 $expires = $response->getHeader("Expires", Header::class);
  85                 if ($expires) {
  86                         if ($expires->match(0, Header::MATCH_FULL)) {
  87                                 return 0;
  88                         }
  89
  90                         $date = $response->getHeader("Date", Header::class);
  91                         if ($date) {
  92                                 return strtotime($expires->value) - strtotime($date->value);
  93                         }
  94                 }
  95
  96                 return -1;
  97         }
  98
  99         /**
 100          * @param Request $request
 101          * @return string
 102          */
 103         private function extractAuth(Request $request) : string {
 104                 $auth = $request->getHeader("Authorization");
 105                 if ($auth) {
 106                         return substr($auth, strpos($auth, " ") + 1);
 107                 }
 108
 109                 $opts = $request->getOptions();
 110                 if (isset($opts["httpauth"])) {
 111                         return base64_encode($opts["httpauth"]);
 112                 }
 113
 114                 $query = new QueryString((new Url($request->getRequestUrl()))->query);
 115                 return $query->getString("access_token", $query->getString("client_id", ""));
 116         }
 117 }