application/bookmark/BookmarkIO.php

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