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