includes/libs/objectcache/SerializedValueContainer.php

   1 <?php
   2
   3 namespace Wikimedia\ObjectCache;
   4
   5 use stdClass;
   6
   7 /**
   8  * Helper class for segmenting large cache values without relying
   9  * on serializing classes.
  10  *
  11  * @internal
  12  * @since 1.34
  13  * @ingroup Cache
  14  */
  15 class SerializedValueContainer {
  16         private const SCHEMA = '__svc_schema__';
  17         // 64 bit UID
  18         private const SCHEMA_SEGMENTED = 'CAYCDAgCDw4';
  19         public const SEGMENTED_HASHES = '__hashes__';
  20
  21         /**
  22          * @param string[] $segmentHashList Ordered list of hashes for each segment
  23          * @return stdClass
  24          */
  25         public static function newSegmented( array $segmentHashList ) {
  26                 return (object)[
  27                         self::SCHEMA => self::SCHEMA_SEGMENTED,
  28                         self::SEGMENTED_HASHES => $segmentHashList
  29                 ];
  30         }
  31
  32         /**
  33          * @param mixed $value
  34          * @return bool
  35          */
  36         public static function isSegmented( $value ): bool {
  37                 return (
  38                         $value instanceof stdClass &&
  39                         ( $value->{self::SCHEMA} ?? null ) === self::SCHEMA_SEGMENTED
  40                 );
  41         }
  42 }