diff --git a/application/LinkDB.php b/application/LinkDB.php index c8b162b6..e429ab4f 100644 --- a/application/LinkDB.php +++ b/application/LinkDB.php @@ -6,15 +6,15 @@ * * Example: * $myLinks = new LinkDB(); - * echo $myLinks['20110826_161819']['title']; + * echo $myLinks[350]['title']; * foreach ($myLinks as $link) * echo $link['title'].' at url '.$link['url'].'; description:'.$link['description']; * * Available keys: + * - id: primary key, incremental integer identifier (persistent) * - description: description of the entry - * - linkdate: creation date of this entry, format: YYYYMMDD_HHMMSS - * (e.g.'20110914_192317') - * - updated: last modification date of this entry, format: YYYYMMDD_HHMMSS + * - created: creation date of this entry, DateTime object. + * - updated: last modification date of this entry, DateTime object. * - private: Is this link private? 0=no, other value=yes * - tags: tags attached to this entry (separated by spaces) * - title Title of the link @@ -27,6 +27,19 @@ * - ArrayAccess: behaves like an associative array; * - Countable: there is a count() method; * - Iterator: usable in foreach () loops. + * + * ID mechanism: + * ArrayAccess is implemented in a way that will allow to access a link + * with the unique identifier ID directly with $link[ID]. + * Note that it's not the real key of the link array attribute. + * This mechanism is in place to have persistent link IDs, + * even though the internal array is reordered by date. + * Example: + * - DB: link #1 (2010-01-01) link #2 (2016-01-01) + * - Order: #2 #1 + * - Import links containing: link #3 (2013-01-01) + * - New DB: link #1 (2010-01-01) link #2 (2016-01-01) link #3 (2013-01-01) + * - Real order: #2 #3 #1 */ class LinkDB implements Iterator, Countable, ArrayAccess { @@ -47,11 +60,17 @@ class LinkDB implements Iterator, Countable, ArrayAccess // - value: associative array (keys: title, description...) private $links; - // List of all recorded URLs (key=url, value=linkdate) - // for fast reserve search (url-->linkdate) + // List of all recorded URLs (key=url, value=link offset) + // for fast reserve search (url-->link offset) private $urls; - // List of linkdate keys (for the Iterator interface implementation) + /** + * @var array List of all links IDS mapped with their array offset. + * Map: id->offset. + */ + protected $ids; + + // List of offset keys (for the Iterator interface implementation) private $keys; // Position in the $this->keys array (for the Iterator interface) @@ -121,14 +140,26 @@ public function offsetSet($offset, $value) if (!$this->loggedIn) { die('You are not authorized to add a link.'); } - if (empty($value['linkdate']) || empty($value['url'])) { - die('Internal Error: A link should always have a linkdate and URL.'); + if (!isset($value['id']) || empty($value['url'])) { + die('Internal Error: A link should always have an id and URL.'); } - if (empty($offset)) { - die('You must specify a key.'); + if ((! empty($offset) && ! is_int($offset)) || ! is_int($value['id'])) { + die('You must specify an integer as a key.'); + } + if (! empty($offset) && $offset !== $value['id']) { + die('Array offset and link ID must be equal.'); + } + + // If the link exists, we reuse the real offset, otherwise new entry + $existing = $this->getLinkOffset($offset); + if ($existing !== null) { + $offset = $existing; + } else { + $offset = count($this->links); } $this->links[$offset] = $value; - $this->urls[$value['url']]=$offset; + $this->urls[$value['url']] = $offset; + $this->ids[$value['id']] = $offset; } /** @@ -136,7 +167,7 @@ public function offsetSet($offset, $value) */ public function offsetExists($offset) { - return array_key_exists($offset, $this->links); + return array_key_exists($this->getLinkOffset($offset), $this->links); } /** @@ -148,9 +179,11 @@ public function offsetUnset($offset) // TODO: raise an exception die('You are not authorized to delete a link.'); } - $url = $this->links[$offset]['url']; + $realOffset = $this->getLinkOffset($offset); + $url = $this->links[$realOffset]['url']; unset($this->urls[$url]); - unset($this->links[$offset]); + unset($this->ids[$realOffset]); + unset($this->links[$realOffset]); } /** @@ -158,7 +191,8 @@ public function offsetUnset($offset) */ public function offsetGet($offset) { - return isset($this->links[$offset]) ? $this->links[$offset] : null; + $realOffset = $this->getLinkOffset($offset); + return isset($this->links[$realOffset]) ? $this->links[$realOffset] : null; } /** @@ -166,7 +200,7 @@ public function offsetGet($offset) */ public function current() { - return $this->links[$this->keys[$this->position]]; + return $this[$this->keys[$this->position]]; } /** @@ -192,8 +226,7 @@ public function next() */ public function rewind() { - $this->keys = array_keys($this->links); - rsort($this->keys); + $this->keys = array_keys($this->ids); $this->position = 0; } @@ -219,6 +252,7 @@ private function check() // Create a dummy database for example $this->links = array(); $link = array( + 'id' => 1, 'title'=>' Shaarli: the personal, minimalist, super-fast, no-database delicious clone', 'url'=>'https://github.com/shaarli/Shaarli/wiki', 'description'=>'Welcome to Shaarli! This is your first public bookmark. To edit or delete me, you must first login. @@ -227,20 +261,21 @@ private function check() You use the community supported version of the original Shaarli project, by Sebastien Sauvage.', 'private'=>0, - 'linkdate'=> date('Ymd_His'), + 'created'=> new DateTime(), 'tags'=>'opensource software' ); - $this->links[$link['linkdate']] = $link; + $this->links[1] = $link; $link = array( + 'id' => 0, 'title'=>'My secret stuff... - Pastebin.com', 'url'=>'http://sebsauvage.net/paste/?8434b27936c09649#bR7XsXhoTiLcqCpQbmOpBi3rq2zzQUC5hBI7ZT1O3x8=', 'description'=>'Shhhh! I\'m a private link only YOU can see. You can delete me too.', 'private'=>1, - 'linkdate'=> date('Ymd_His', strtotime('-1 minute')), + 'created'=> new DateTime('1 minute ago'), 'tags'=>'secretstuff' ); - $this->links[$link['linkdate']] = $link; + $this->links[0] = $link; // Write database to disk $this->write(); @@ -251,7 +286,6 @@ private function check() */ private function read() { - // Public links are hidden and user not logged in => nothing to show if ($this->hidePublicLinks && !$this->loggedIn) { $this->links = array(); @@ -269,23 +303,13 @@ private function read() strlen(self::$phpPrefix), -strlen(self::$phpSuffix))))); } - // If user is not logged in, filter private links. - if (!$this->loggedIn) { - $toremove = array(); - foreach ($this->links as $link) { - if ($link['private'] != 0) { - $toremove[] = $link['linkdate']; - } + $toremove = array(); + foreach ($this->links as $key => &$link) { + if (! $this->loggedIn && $link['private'] != 0) { + // Transition for not upgraded databases. + $toremove[] = $key; + continue; } - foreach ($toremove as $linkdate) { - unset($this->links[$linkdate]); - } - } - - $this->urls = array(); - foreach ($this->links as &$link) { - // Keep the list of the mapping URLs-->linkdate up-to-date. - $this->urls[$link['url']] = $link['linkdate']; // Sanitize data fields. sanitizeLink($link); @@ -307,7 +331,23 @@ private function read() else { $link['real_url'] = $link['url']; } + + // To be able to load links before running the update, and prepare the update + if (! isset($link['created'])) { + $link['id'] = $link['linkdate']; + $link['created'] = DateTime::createFromFormat('Ymd_His', $link['linkdate']); + if (! empty($link['updated'])) { + $link['updated'] = DateTime::createFromFormat('Ymd_His', $link['updated']); + } + } } + + // If user is not logged in, filter private links. + foreach ($toremove as $offset) { + unset($this->links[$offset]); + } + + $this->reorder(); } /** @@ -430,7 +470,7 @@ public function filterSearch($filterRequest = array(), $casesensitive = false, $ $request = ''; } - $linkFilter = new LinkFilter($this->links); + $linkFilter = new LinkFilter($this); return $linkFilter->filter($type, $request, $casesensitive, $privateonly); } @@ -467,12 +507,64 @@ public function allTags() public function days() { $linkDays = array(); - foreach (array_keys($this->links) as $day) { - $linkDays[substr($day, 0, 8)] = 0; + foreach ($this->links as $link) { + $linkDays[$link['created']->format('Ymd')] = 0; } $linkDays = array_keys($linkDays); sort($linkDays); return $linkDays; } + + /** + * Reorder links by creation date (newest first). + * + * Also update the urls and ids mapping arrays. + * + * @param string $order ASC|DESC + */ + public function reorder($order = 'DESC') + { + $order = $order === 'ASC' ? -1 : 1; + // Reorder array by dates. + usort($this->links, function($a, $b) use ($order) { + return $a['created'] < $b['created'] ? 1 * $order : -1 * $order; + }); + + $this->urls = array(); + $this->ids = array(); + foreach ($this->links as $key => $link) { + $this->urls[$link['url']] = $key; + $this->ids[$link['id']] = $key; + } + } + + /** + * Return the next key for link creation. + * E.g. If the last ID is 597, the next will be 598. + * + * @return int next ID. + */ + public function getNextId() + { + if (!empty($this->ids)) { + return max(array_keys($this->ids)) + 1; + } + return 0; + } + + /** + * Returns a link offset in links array from its unique ID. + * + * @param int $id Persistent ID of a link. + * + * @return int Real offset in local array, or null if doesn't exists. + */ + protected function getLinkOffset($id) + { + if (isset($this->ids[$id])) { + return $this->ids[$id]; + } + return null; + } }