]> git.mxchange.org Git - friendica.git/blobdiff - src/Model/Tag.php
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[friendica.git] / src / Model / Tag.php
index 0a3e0e85337f6def2a7535e0fd301681390f406a..1cc48bd2f7dca5572e2cafa9517d42c335e60ae2 100644 (file)
@@ -1,6 +1,6 @@
 <?php
 /**
- * @copyright Copyright (C) 2020, Friendica
+ * @copyright Copyright (C) 2010-2022, the Friendica project
  *
  * @license GNU AGPL version 3 or any later version
  *
 namespace Friendica\Model;
 
 use Friendica\Content\Text\BBCode;
-use Friendica\Core\Cache\Duration;
+use Friendica\Core\Cache\Enum\Duration;
 use Friendica\Core\Logger;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
+use Friendica\Database\Database;
 use Friendica\Database\DBA;
 use Friendica\DI;
+use Friendica\Util\DateTimeFormat;
 use Friendica\Util\Strings;
 
 /**
@@ -40,22 +43,25 @@ class Tag
        const UNKNOWN  = 0;
        const HASHTAG  = 1;
        const MENTION  = 2;
-       const CATEGORY = 3;
-       const FILE     = 5;
        /**
         * An implicit mention is a mention in a comment body that is redundant with the threading information.
         */
        const IMPLICIT_MENTION  = 8;
        /**
-        * An exclusive mention transfers the ownership of the post to the target account, usually a forum.
+        * An exclusive mention transmits the post only to the target account without transmitting it to the followers, usually a forum.
         */
        const EXCLUSIVE_MENTION = 9;
 
+       const TO  = 10;
+       const CC  = 11;
+       const BTO = 12;
+       const BCC = 13;
+
        const TAG_CHARACTER = [
                self::HASHTAG           => '#',
                self::MENTION           => '@',
-               self::IMPLICIT_MENTION  => '%',
                self::EXCLUSIVE_MENTION => '!',
+               self::IMPLICIT_MENTION  => '%',
        ];
 
        /**
@@ -65,18 +71,17 @@ class Tag
         * @param integer $type
         * @param string  $name
         * @param string  $url
-        * @param boolean $probing
         */
-       public static function store(int $uriid, int $type, string $name, string $url = '', $probing = true)
+       public static function store(int $uriid, int $type, string $name, string $url = '')
        {
                if ($type == self::HASHTAG) {
-                       // Remove some common "garbarge" from tags
-                       $name = trim($name, "\x00..\x20\xFF#!@,;.:'/?!^°$%".'"');
+                       // Trim Unicode non-word characters
+                       $name = preg_replace('/(^\W+)|(\W+$)/us', '', $name);
 
                        $tags = explode(self::TAG_CHARACTER[self::HASHTAG], $name);
                        if (count($tags) > 1) {
                                foreach ($tags as $tag) {
-                                       self::store($uriid, $type, $tag, $url, $probing);
+                                       self::store($uriid, $type, $tag, $url);
                                }
                                return;
                        }
@@ -89,59 +94,40 @@ class Tag
                $cid = 0;
                $tagid = 0;
 
-               if (in_array($type, [self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION])) {
+               if (in_array($type, [self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION, self::TO, self::CC, self::BTO, self::BCC])) {
                        if (empty($url)) {
                                // No mention without a contact url
                                return;
                        }
 
-                       if (!$probing) {
-                               $condition = ['nurl' => Strings::normaliseLink($url), 'uid' => 0, 'deleted' => false];
-                               $contact = DBA::selectFirst('contact', ['id'], $condition, ['order' => ['id']]);
-                               if (DBA::isResult($contact)) {
-                                       $cid = $contact['id'];
-                                       Logger::info('Got id for contact url', ['cid' => $cid, 'url' => $url]);
-                               }
-
-                               if (empty($cid)) {
-                                       $ssl_url = str_replace('http://', 'https://', $url);
-                                       $condition = ['`alias` IN (?, ?, ?) AND `uid` = ? AND NOT `deleted`', $url, Strings::normaliseLink($url), $ssl_url, 0];
-                                       $contact = DBA::selectFirst('contact', ['id'], $condition, ['order' => ['id']]);
-                                       if (DBA::isResult($contact)) {
-                                               $cid = $contact['id'];
-                                               Logger::info('Got id for contact alias', ['cid' => $cid, 'url' => $url]);
-                                       }
-                               }
-                       } else {
-                               $cid = Contact::getIdForURL($url, 0, true);
-                               Logger::info('Got id by probing', ['cid' => $cid, 'url' => $url]);
+                       if ((substr($url, 0, 7) == 'https//') || (substr($url, 0, 6) == 'http//')) {
+                               Logger::notice('Wrong scheme in url', ['url' => $url, 'callstack' => System::callstack(20)]);
                        }
 
+                       $cid = Contact::getIdForURL($url, 0, false);
+                       Logger::debug('Got id for contact', ['cid' => $cid, 'url' => $url]);
+
                        if (empty($cid)) {
                                // The contact wasn't found in the system (most likely some dead account)
                                // We ensure that we only store a single entry by overwriting the previous name
-                               Logger::info('Contact not found, updating tag', ['url' => $url, 'name' => $name]);
-                               DBA::update('tag', ['name' => substr($name, 0, 96)], ['url' => $url]);
+                               Logger::info('URL is not a known contact, updating tag', ['url' => $url, 'name' => $name]);
+                               if (!DBA::exists('tag', ['name' => substr($name, 0, 96), 'url' => $url])) {
+                                       DBA::update('tag', ['name' => substr($name, 0, 96)], ['url' => $url]);
+                               }
                        }
                }
 
                if (empty($cid)) {
-                       $fields = ['name' => substr($name, 0, 96), 'url' => ''];
-
-                       if (($type != self::HASHTAG) && !empty($url) && ($url != $name)) {
-                               $fields['url'] = strtolower($url);
-                       }
-
-                       $tag = DBA::selectFirst('tag', ['id'], $fields);
-                       if (!DBA::isResult($tag)) {
-                               DBA::insert('tag', $fields, true);
-                               $tagid = DBA::lastInsertId();
-                       } else {
-                               $tagid = $tag['id'];
+                       if (!in_array($type, [self::TO, self::CC, self::BTO, self::BCC])) {
+                               if (($type != self::HASHTAG) && !empty($url) && ($url != $name)) {
+                                       $url = strtolower($url);
+                               } else {
+                                       $url = '';
+                               }
                        }
 
+                       $tagid = self::getID($name, $url);
                        if (empty($tagid)) {
-                               Logger::error('No tag id created', $fields);
                                return;
                        }
                }
@@ -157,11 +143,37 @@ class Tag
                        }
                }
 
-               DBA::insert('post-tag', $fields, true);
+               DBA::insert('post-tag', $fields, Database::INSERT_IGNORE);
 
                Logger::info('Stored tag/mention', ['uri-id' => $uriid, 'tag-id' => $tagid, 'contact-id' => $cid, 'name' => $name, 'type' => $type, 'callstack' => System::callstack(8)]);
        }
 
+       /**
+        * Get a tag id for a given tag name and url
+        *
+        * @param string $name
+        * @param string $url
+        * @return void
+        */
+       public static function getID(string $name, string $url = '')
+       {
+               $fields = ['name' => substr($name, 0, 96), 'url' => $url];
+
+               $tag = DBA::selectFirst('tag', ['id'], $fields);
+               if (DBA::isResult($tag)) {
+                       return $tag['id'];
+               }
+
+               DBA::insert('tag', $fields, Database::INSERT_IGNORE);
+               $tid = DBA::lastInsertId();
+               if (!empty($tid)) {
+                       return $tid;
+               }
+
+               Logger::error('No tag id created', $fields);
+               return 0;
+       }
+
        /**
         * Store tag/mention elements
         *
@@ -182,22 +194,40 @@ class Tag
        }
 
        /**
-        * Store tags and mentions from the body
+        * Get tags and mentions from the body
         * 
-        * @param integer $uriid   URI-Id
         * @param string  $body    Body of the post
         * @param string  $tags    Accepted tags
-        * @param boolean $probing Perform a probing for contacts, adding them if needed
+        *
+        * @return array Tag list
         */
-       public static function storeFromBody(int $uriid, string $body, string $tags = null, $probing = true)
+       public static function getFromBody(string $body, string $tags = null)
        {
                if (is_null($tags)) {
                        $tags =  self::TAG_CHARACTER[self::HASHTAG] . self::TAG_CHARACTER[self::MENTION] . self::TAG_CHARACTER[self::EXCLUSIVE_MENTION];
                }
 
+               if (!preg_match_all("/([" . $tags . "])\[url\=([^\[\]]*)\]([^\[\]]*)\[\/url\]/ism", $body, $result, PREG_SET_ORDER)) {
+                       return [];
+               }
+
+               return $result;
+       }
+
+       /**
+        * Store tags and mentions from the body
+        * 
+        * @param integer $uriid   URI-Id
+        * @param string  $body    Body of the post
+        * @param string  $tags    Accepted tags
+        * @param boolean $probing Perform a probing for contacts, adding them if needed
+        */
+       public static function storeFromBody(int $uriid, string $body, string $tags = null, $probing = true)
+       {
                Logger::info('Check for tags', ['uri-id' => $uriid, 'hash' => $tags, 'callstack' => System::callstack()]);
 
-               if (!preg_match_all("/([" . $tags . "])\[url\=([^\[\]]*)\]([^\[\]]*)\[\/url\]/ism", $body, $result, PREG_SET_ORDER)) {
+               $result = self::getFromBody($body, $tags);
+               if (empty($result)) {
                        return;
                }
 
@@ -243,7 +273,7 @@ class Tag
         */
        public static function existsForPost(int $uriid)
        {
-               return DBA::exists('post-tag', ['uri-id' => $uriid, 'type' => [self::HASHTAG, self::MENTION, self::IMPLICIT_MENTION, self::EXCLUSIVE_MENTION]]);
+               return DBA::exists('post-tag', ['uri-id' => $uriid, 'type' => [self::HASHTAG, self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION]]);
        }
 
        /**
@@ -309,6 +339,29 @@ class Tag
                }
        }
 
+       /**
+        * Create implicit mentions for a given post
+        *
+        * @param integer $uri_id
+        * @param integer $parent_uri_id
+        */
+       public static function createImplicitMentions(int $uri_id, int $parent_uri_id)
+       {
+               // Always mention the direct parent author
+               $parent = Post::selectFirst(['author-link', 'author-name'], ['uri-id' => $parent_uri_id]);
+               self::store($uri_id, self::IMPLICIT_MENTION, $parent['author-name'], $parent['author-link']);
+
+               if (DI::config()->get('system', 'disable_implicit_mentions')) {
+                       return;
+               }
+
+               $tags = DBA::select('tag-view', ['name', 'url'], ['uri-id' => $parent_uri_id, 'type' => [self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION]]);
+               while ($tag = DBA::fetch($tags)) {
+                       self::store($uri_id, self::IMPLICIT_MENTION, $tag['name'], $tag['url']);
+               }
+               DBA::close($tags);
+       }
+
        /**
         * Retrieves the terms from the provided type(s) associated with the provided item ID.
         *
@@ -317,21 +370,29 @@ class Tag
         * @return array
         * @throws \Exception
         */
-       public static function getByURIId(int $uri_id, array $type = [self::HASHTAG, self::MENTION, self::IMPLICIT_MENTION, self::EXCLUSIVE_MENTION])
+       public static function getByURIId(int $uri_id, array $type = [self::HASHTAG, self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION])
        {
                $condition = ['uri-id' => $uri_id, 'type' => $type];
-               $tags = DBA::select('tag-view', ['type', 'name', 'url'], $condition);
-               if (!DBA::isResult($tags)) {
-                       return [];
-               }
+               return DBA::selectToArray('tag-view', ['type', 'name', 'url'], $condition);
+       }
 
+       /**
+        * Return a string with all tags and mentions
+        *
+        * @param integer $uri_id
+        * @param array   $type
+        * @return string tags and mentions
+        * @throws \Exception
+        */
+       public static function getCSVByURIId(int $uri_id, array $type = [self::HASHTAG, self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION])
+       {
                $tag_list = [];
-               while ($tag = DBA::fetch($tags)) {
-                       $tag['term'] = $tag['name']; /// @todo Remove this line when all occurrences of "term" had been replaced with "name"
-                       $tag_list[] = $tag;
+               $tags = self::getByURIId($uri_id, $type);
+               foreach ($tags as $tag) {
+                       $tag_list[] = self::TAG_CHARACTER[$tag['type']] . '[url=' . $tag['url'] . ']' . $tag['name'] . '[/url]';
                }
 
-               return $tag_list;
+               return implode(',', $tag_list);
        }
 
        /**
@@ -354,7 +415,7 @@ class Tag
 
                $searchpath = DI::baseUrl() . "/search?tag=";
 
-               $taglist = DBA::select('tag-view', ['type', 'name', 'url'],
+               $taglist = DBA::select('tag-view', ['type', 'name', 'url', 'cid'],
                        ['uri-id' => $item['uri-id'], 'type' => [self::HASHTAG, self::MENTION, self::EXCLUSIVE_MENTION, self::IMPLICIT_MENTION]]);
                while ($tag = DBA::fetch($taglist)) {
                        if ($tag['url'] == '') {
@@ -370,14 +431,18 @@ class Tag
                                                $item['body'] = str_replace($orig_tag, $tag['url'], $item['body']);
                                        }
 
-                                       $return['hashtags'][] = $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a>';
-                                       $return['tags'][] = $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a>';
+                                       $return['hashtags'][] = '<bdi>' . $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a></bdi>';
+                                       $return['tags'][] = '<bdi>' . $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a></bdi>';
                                        break;
                                case self::MENTION:
                                case self::EXCLUSIVE_MENTION:
+                                       if (!empty($tag['cid'])) {
+                                               $tag['url'] = Contact::magicLinkById($tag['cid']);
+                                       } else {
                                                $tag['url'] = Contact::magicLink($tag['url']);
-                                       $return['mentions'][] = $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a>';
-                                       $return['tags'][] = $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a>';
+                                       }
+                                       $return['mentions'][] = '<bdi>' . $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a></bdi>';
+                                       $return['tags'][] = '<bdi>' . $prefix . '<a href="' . $tag['url'] . '" target="_blank" rel="noopener noreferrer">' . htmlspecialchars($tag['name']) . '</a></bdi>';
                                        break;
                                case self::IMPLICIT_MENTION:
                                        $return['implicit_mentions'][] = $prefix . $tag['name'];
@@ -389,6 +454,22 @@ class Tag
                return $return;
        }
 
+       /**
+        * Counts posts for given tag
+        *
+        * @param string $search
+        * @param integer $uid
+        * @return integer number of posts
+        */
+       public static function countByTag(string $search, int $uid = 0)
+       {
+               $condition = ["`name` = ? AND (`uid` = ? OR (`uid` = ? AND NOT `global`))
+                       AND (`network` IN (?, ?, ?, ?) OR (`uid` = ? AND `uid` != ?))",
+                       $search, 0, $uid, Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, $uid, 0];
+
+               return DBA::count('tag-search-view', $condition);
+       }
+
        /**
         * Search posts for given tag
         *
@@ -396,14 +477,21 @@ class Tag
         * @param integer $uid
         * @param integer $start
         * @param integer $limit
+        * @param integer $last_uriid
         * @return array with URI-ID
         */
-       public static function getURIIdListForTag(string $search, int $uid = 0, int $start = 0, int $limit = 100)
+       public static function getURIIdListByTag(string $search, int $uid = 0, int $start = 0, int $limit = 100, int $last_uriid = 0)
        {
-               $condition = ["`name` = ? AND (NOT `private` OR (`private` AND `uid` = ?))", $search, $uid];
+               $condition = ["`name` = ? AND (`uid` = ? OR (`uid` = ? AND NOT `global`))
+                       AND (`network` IN (?, ?, ?, ?) OR (`uid` = ? AND `uid` != ?))",
+                       $search, 0, $uid, Protocol::ACTIVITYPUB, Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, $uid, 0];
+
+               if (!empty($last_uriid)) {
+                       $condition = DBA::mergeConditions($condition, ["`uri-id` < ?", $last_uriid]);
+               }
+
                $params = [
                        'order' => ['uri-id' => true],
-                       'group_by' => ['uri-id'],
                        'limit' => [$start, $limit]
                ];
 
@@ -422,53 +510,177 @@ class Tag
         * Returns a list of the most frequent global hashtags over the given period
         *
         * @param int $period Period in hours to consider posts
+        * @param int $limit  Number of returned tags
         * @return array
         * @throws \Exception
         */
        public static function getGlobalTrendingHashtags(int $period, $limit = 10)
        {
-               $tags = DI::cache()->get('global_trending_tags');
-
-               if (empty($tags)) {
-                       $tagsStmt = DBA::p("SELECT `name` AS `term`, COUNT(*) AS `score`
-                               FROM `tag-search-view`
-                               WHERE `private` = ? AND `received` > DATE_SUB(NOW(), INTERVAL ? HOUR)
-                               GROUP BY `term` ORDER BY `score` DESC LIMIT ?",
-                               Item::PUBLIC, $period, $limit);
-
-                       if (DBA::isResult($tagsStmt)) {
-                               $tags = DBA::toArray($tagsStmt);
-                               DI::cache()->set('global_trending_tags', $tags, Duration::HOUR);
-                       }
+               $tags = DI::cache()->get('global_trending_tags-' . $period . '-' . $limit);
+               if (!empty($tags)) {
+                       return $tags;
+               } else {
+                       return self::setGlobalTrendingHashtags($period, $limit);
+               }
+       }
+
+       /**
+        * Fetch the blocked tags as SQL
+        *
+        * @return string 
+        */
+       private static function getBlockedSQL()
+       {
+               $blocked_txt = DI::config()->get('system', 'blocked_tags');
+               if (empty($blocked_txt)) {
+                       return '';
                }
 
-               return $tags ?: [];
+               $blocked = explode(',', $blocked_txt);
+               array_walk($blocked, function(&$value) { $value = "'" . DBA::escape(trim($value)) . "'";});
+               return " AND NOT `name` IN (" . implode(',', $blocked) . ")";
+       }
+
+       /**
+        * Creates a list of the most frequent global hashtags over the given period
+        *
+        * @param int $period Period in hours to consider posts
+        * @param int $limit  Number of returned tags
+        * @return array
+        * @throws \Exception
+        */
+       public static function setGlobalTrendingHashtags(int $period, int $limit = 10)
+       {
+               // Get a uri-id that is at least X hours old.
+               // We use the uri-id in the query for the hash tags since this is much faster
+               $post = Post::selectFirstThread(['uri-id'], ["`uid` = ? AND `received` < ?", 0, DateTimeFormat::utc('now - ' . $period . ' hour')],
+                       ['order' => ['received' => true]]);
+               if (empty($post['uri-id'])) {
+                       return [];
+               }
+
+               $block_sql = self::getBlockedSQL();
+
+               $tagsStmt = DBA::p("SELECT `name` AS `term`, COUNT(*) AS `score`, COUNT(DISTINCT(`author-id`)) as `authors`
+                       FROM `tag-search-view`
+                       WHERE `private` = ? AND `uid` = ? AND `uri-id` > ? $block_sql
+                       GROUP BY `term` ORDER BY `authors` DESC, `score` DESC LIMIT ?",
+                       Item::PUBLIC, 0, $post['uri-id'], $limit);
+
+               if (DBA::isResult($tagsStmt)) {
+                       $tags = DBA::toArray($tagsStmt);
+                       DI::cache()->set('global_trending_tags-' . $period . '-' . $limit, $tags, Duration::DAY);
+                       return $tags;
+               }
+
+               return [];
        }
 
        /**
         * Returns a list of the most frequent local hashtags over the given period
         *
         * @param int $period Period in hours to consider posts
+        * @param int $limit  Number of returned tags
         * @return array
         * @throws \Exception
         */
        public static function getLocalTrendingHashtags(int $period, $limit = 10)
        {
-               $tags = DI::cache()->get('local_trending_tags');
-
-               if (empty($tags)) {
-                       $tagsStmt = DBA::p("SELECT `name` AS `term`, COUNT(*) AS `score`
-                               FROM `tag-search-view`
-                               WHERE `private` = ? AND `wall` AND `origin` AND `received` > DATE_SUB(NOW(), INTERVAL ? HOUR)
-                               GROUP BY `term` ORDER BY `score` DESC LIMIT ?",
-                               Item::PUBLIC, $period, $limit);
-
-                       if (DBA::isResult($tagsStmt)) {
-                               $tags = DBA::toArray($tagsStmt);
-                               DI::cache()->set('local_trending_tags', $tags, Duration::HOUR);
+               $tags = DI::cache()->get('local_trending_tags-' . $period . '-' . $limit);
+               if (!empty($tags)) {
+                       return $tags;
+               } else {
+                       return self::setLocalTrendingHashtags($period, $limit);
+               }
+       }
+
+       /**
+        * Returns a list of the most frequent local hashtags over the given period
+        *
+        * @param int $period Period in hours to consider posts
+        * @param int $limit  Number of returned tags
+        * @return array
+        * @throws \Exception
+        */
+       public static function setLocalTrendingHashtags(int $period, int $limit = 10)
+       {
+               // Get a uri-id that is at least X hours old.
+               // We use the uri-id in the query for the hash tags since this is much faster
+               $post = Post::selectFirstThread(['uri-id'], ["`uid` = ? AND `received` < ?", 0, DateTimeFormat::utc('now - ' . $period . ' hour')],
+                       ['order' => ['received' => true]]);
+               if (empty($post['uri-id'])) {
+                       return [];
+               }
+
+               $block_sql = self::getBlockedSQL();
+
+               $tagsStmt = DBA::p("SELECT `name` AS `term`, COUNT(*) AS `score`, COUNT(DISTINCT(`author-id`)) as `authors`
+                       FROM `tag-search-view`
+                       WHERE `private` = ? AND `wall` AND `origin` AND `uri-id` > ? $block_sql
+                       GROUP BY `term` ORDER BY `authors` DESC, `score` DESC LIMIT ?",
+                       Item::PUBLIC, $post['uri-id'], $limit);
+
+               if (DBA::isResult($tagsStmt)) {
+                       $tags = DBA::toArray($tagsStmt);
+                       DI::cache()->set('local_trending_tags-' . $period . '-' . $limit, $tags, Duration::DAY);
+                       return $tags;
+               }
+
+               return [];
+       }
+
+       /**
+        * Check if the provided tag is of one of the provided term types.
+        *
+        * @param string $tag
+        * @param int    ...$types
+        * @return bool
+        */
+       public static function isType($tag, ...$types)
+       {
+               $tag_chars = [];
+               foreach ($types as $type) {
+                       if (array_key_exists($type, self::TAG_CHARACTER)) {
+                               $tag_chars[] = self::TAG_CHARACTER[$type];
                        }
                }
 
-               return $tags ?: [];
+               return Strings::startsWithChars($tag, $tag_chars);
+       }
+
+       /**
+        * Fetch user who subscribed to the given tag
+        *
+        * @param string $tag
+        * @return array User list
+        */
+       private static function getUIDListByTag(string $tag)
+       {
+               $uids = [];
+               $searches = DBA::select('search', ['uid'], ['term' => $tag]);
+               while ($search = DBA::fetch($searches)) {
+                       $uids[] = $search['uid'];
+               }
+               DBA::close($searches);
+
+               return $uids;
+       }
+
+       /**
+        * Fetch user who subscribed to the tags of the given item
+        *
+        * @param integer $uri_id
+        * @return array User list
+        */
+       public static function getUIDListByURIId(int $uri_id)
+       {
+               $uids = [];
+               $tags = self::getByURIId($uri_id, [self::HASHTAG]);
+
+               foreach ($tags as $tag) {
+                       $uids = array_merge($uids, self::getUIDListByTag(self::TAG_CHARACTER[self::HASHTAG] . $tag['name']));
+               }
+
+               return array_unique($uids);
        }
 }