application/bookmark/BookmarkIO.php

   1 <?php
   2
   3 namespace Shaarli\Bookmark;
   4
   5 use Shaarli\Bookmark\Exception\EmptyDataStoreException;
   6 use Shaarli\Bookmark\Exception\NotWritableDataStoreException;
   7 use Shaarli\Config\ConfigManager;
   8
   9 /**
  10  * Class BookmarkIO
  11  *
  12  * This class performs read/write operation to the file data store.
  13  * Used by BookmarkFileService.
  14  *
  15  * @package Shaarli\Bookmark
  16  */
  17 class BookmarkIO
  18 {
  19     /**
  20      * @var string Datastore file path
  21      */
  22     protected $datastore;
  23
  24     /**
  25      * @var ConfigManager instance
  26      */
  27     protected $conf;
  28
  29     /**
  30      * string Datastore PHP prefix
  31      */
  32     protected static $phpPrefix = '<?php /* ';
  33
  34     /**
  35      * string Datastore PHP suffix
  36      */
  37     protected static $phpSuffix = ' */ ?>';
  38
  39     /**
  40      * LinksIO constructor.
  41      *
  42      * @param ConfigManager $conf instance
  43      */
  44     public function __construct($conf)
  45     {
  46         $this->conf = $conf;
  47         $this->datastore = $conf->get('resource.datastore');
  48     }
  49
  50     /**
  51      * Reads database from disk to memory
  52      *
  53      * @return BookmarkArray instance
  54      *
  55      * @throws NotWritableDataStoreException Data couldn't be loaded
  56      * @throws EmptyDataStoreException       Datastore doesn't exist
  57      */
  58     public function read()
  59     {
  60         if (! file_exists($this->datastore)) {
  61             throw new EmptyDataStoreException();
  62         }
  63
  64         if (!is_writable($this->datastore)) {
  65             throw new NotWritableDataStoreException($this->datastore);
  66         }
  67
  68         // Note that gzinflate is faster than gzuncompress.
  69         // See: http://www.php.net/manual/en/function.gzdeflate.php#96439
  70         $links = unserialize(gzinflate(base64_decode(
  71             substr(file_get_contents($this->datastore),
  72                 strlen(self::$phpPrefix), -strlen(self::$phpSuffix)))));
  73
  74         if (empty($links)) {
  75             if (filesize($this->datastore) > 100) {
  76                 throw new NotWritableDataStoreException($this->datastore);
  77             }
  78             throw new EmptyDataStoreException();
  79         }
  80
  81         return $links;
  82     }
  83
  84     /**
  85      * Saves the database from memory to disk
  86      *
  87      * @param BookmarkArray $links instance.
  88      *
  89      * @throws NotWritableDataStoreException the datastore is not writable
  90      */
  91     public function write($links)
  92     {
  93         if (is_file($this->datastore) && !is_writeable($this->datastore)) {
  94             // The datastore exists but is not writeable
  95             throw new NotWritableDataStoreException($this->datastore);
  96         } else if (!is_file($this->datastore) && !is_writeable(dirname($this->datastore))) {
  97             // The datastore does not exist and its parent directory is not writeable
  98             throw new NotWritableDataStoreException(dirname($this->datastore));
  99         }
 100
 101         file_put_contents(
 102             $this->datastore,
 103             self::$phpPrefix.base64_encode(gzdeflate(serialize($links))).self::$phpSuffix
 104         );
 105
 106         invalidateCaches($this->conf->get('resource.page_cache'));
 107     }
 108 }