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         /**
  15          * @var string
  16          */
  17         private $key;
  18
  19         /**
  20          * @param Request $request
  21          */
  22         function __construct(Request $request) {
  23                 $method = $request->getRequestMethod();
  24                 switch ($method) {
  25                         case "HEAD":
  26                         case "GET":
  27                                 $uid = $this->extractAuth($request);
  28                                 $url = $request->getRequestUrl();
  29                                 $this->key = "seekat call $uid $method $url";
  30                                 break;
  31                         default:
  32                                 $this->key = "";
  33                                 break;
  34                 }
  35         }
  36
  37         /**
  38          * @return bool
  39          */
  40         public function isValid() : bool {
  41                 return strlen($this->key) > 0;
  42         }
  43
  44         /**
  45          * @return string
  46          */
  47         public function getKey() : string {
  48                 return $this->key;
  49         }
  50
  51         /**
  52          * @param Response $response
  53          * @return bool
  54          */
  55         public function isStale(Response $response) : bool {
  56                 if (false === $response->getHeader("Cache-Control") &&
  57                         false === $response->getHeader("Expires")) {
  58                         return false;
  59                 }
  60
  61                 $max_age = $this->extractMaxAge($response);
  62                 $cur_age = time() - $response->getHeader("X-Cache-Time");
  63
  64                 return $max_age >= 0 && $max_age < $cur_age;
  65         }
  66
  67         /**
  68          * @param Response $response
  69          * @return int
  70          */
  71         private function extractMaxAge(Response $response) : int {
  72                 /* @var Header $date
  73                  * @var Header $control
  74                  * @var Header $expires
  75                  */
  76                 $control = $response->getHeader("Cache-Control", Header::class);
  77                 if ($control) {
  78                         /* @var Params $params */
  79                         $params = $control->getParams();
  80                         if (isset($params["max-age"])) {
  81                                 return (int) $params->params["max-age"]["value"];
  82                         }
  83                 }
  84
  85                 $expires = $response->getHeader("Expires", Header::class);
  86                 if ($expires) {
  87                         if ($expires->match(0, Header::MATCH_FULL)) {
  88                                 return 0;
  89                         }
  90
  91                         $date = $response->getHeader("Date", Header::class);
  92                         if ($date) {
  93                                 return strtotime($expires->value) - strtotime($date->value);
  94                         }
  95                 }
  96
  97                 return -1;
  98         }
  99
 100         /**
 101          * @param Request $request
 102          * @return string
 103          */
 104         private function extractAuth(Request $request) : string {
 105                 $auth = $request->getHeader("Authorization");
 106                 if ($auth) {
 107                         return substr($auth, strpos($auth, " ") + 1);
 108                 }
 109
 110                 $opts = $request->getOptions();
 111                 if (isset($opts["httpauth"])) {
 112                         return base64_encode($opts["httpauth"]);
 113                 }
 114
 115                 $query = new QueryString((new Url($request->getRequestUrl()))->query);
 116                 return $query->getString("access_token", $query->getString("client_id", ""));
 117         }
 118 }