Allow to reject specific languages on receiving posts via the relay

src/Model/Item.php

@@ -1870,23 +1870,33 @@ class Item
 			return '';
 		}
 
-		// Convert attachments to links
-		$naked_body = BBCode::removeAttachment($item['body']);
-		if (empty($naked_body)) {
+		$languages = self::getLanguageArray(trim($item['title'] . "\n" . $item['body']));
+		if (empty($languages)) {
 			return '';
 		}
 
+		return json_encode($languages);
+	}
+
+	public static function getLanguageArray(string $body): array
+	{
+		// Convert attachments to links
+		$naked_body = BBCode::removeAttachment($body);
+		if (empty($naked_body)) {
+			return [];
+		}
+
 		// Remove links and pictures
 		$naked_body = BBCode::removeLinks($naked_body);
 
 		// Convert the title and the body to plain text
-		$naked_body = trim($item['title'] . "\n" . BBCode::toPlaintext($naked_body));
+		$naked_body = BBCode::toPlaintext($naked_body);
 
 		// Remove possibly remaining links
 		$naked_body = preg_replace(Strings::autoLinkRegEx(), '', $naked_body);
 
 		if (empty($naked_body)) {
-			return '';
+			return [];
 		}
 
 		$naked_body = self::getDominantLanguage($naked_body);
@@ -1898,12 +1908,7 @@ class Item
 		$availableLanguages['fa'] = 'fa';
 
 		$ld = new Language(array_keys($availableLanguages));
-		$languages = $ld->detect($naked_body)->limit(0, 3)->close();
-		if (is_array($languages)) {
-			return json_encode($languages);
-		}
-
-		return '';
+		return $ld->detect($naked_body)->limit(0, 3)->close() ?: [];
 	}
 
 	/**

src/Protocol/ActivityPub/Processor.php

@@ -91,7 +91,7 @@ class Processor
 	 * @param string $body
 	 * @return string
 	 */
-	protected static function normalizeMentionLinks(string $body): string
+	public static function normalizeMentionLinks(string $body): string
 	{
 		return preg_replace('%\[url=([^\[\]]*)]([#@!])(.*?)\[/url]%ism', '$2[url=$1]$3[/url]', $body);
 	}

src/Protocol/Relay.php

@@ -29,6 +29,7 @@ use Friendica\DI;
 use Friendica\Model\APContact;
 use Friendica\Model\Contact;
 use Friendica\Model\GServer;
+use Friendica\Model\Item;
 use Friendica\Model\Post;
 use Friendica\Model\Search;
 use Friendica\Model\Tag;
@@ -76,6 +77,8 @@ class Relay
 			return false;
 		}
 
+		$body = ActivityPub\Processor::normalizeMentionLinks($body);
+
 		$systemTags = [];
 		$userTags = [];
 		$denyTags = [];
@@ -125,6 +128,25 @@ class Relay
 			}
 		}
 
+		$languages = [];
+		foreach (Item::getLanguageArray($body) as $language => $reliability) {
+			if ($reliability > 0) {
+				$languages[] = $language;
+			}
+		}
+
+		Logger::debug('Got languages', ['languages' => $languages, 'body' => $body]);
+
+		if (!empty($languages)) {
+			if (in_array($languages[0], $config->get('system', 'relay_deny_languages'))) {
+				Logger::info('Unwanted language found - rejected', ['language' => $languages[0], 'network' => $network, 'url' => $url]);
+				return false;
+			}
+		} elseif ($config->get('system', 'relay_deny_undetected_language')) {
+			Logger::info('Undetected language found - rejected', ['body' => $body, 'network' => $network, 'url' => $url]);
+			return false;
+		}
+
 		if ($scope == self::SCOPE_ALL) {
 			Logger::info('Server accept all posts - accepted', ['network' => $network, 'url' => $url]);
 			return true;

src/Util/Profiler.php

@@ -152,13 +152,13 @@ class Profiler implements ContainerInterface
 	 * Saves a timestamp for a value - f.e. a call
 	 * Necessary for profiling Friendica
 	 *
-	 * @param int    $timestamp the Timestamp
+	 * @param float  $timestamp the Timestamp
 	 * @param string $value     A value to profile
 	 * @param string $callstack A callstack string, generated if absent
 	 *
 	 * @return void
 	 */
-	public function saveTimestamp(int $timestamp, string $value, string $callstack = '')
+	public function saveTimestamp(float $timestamp, string $value, string $callstack = '')
 	{
 		if (!$this->enabled) {
 			return;
@@ -358,9 +358,9 @@ class Profiler implements ContainerInterface
 	 * @throws NotFoundExceptionInterface  No entry was found for **this** identifier.
 	 * @throws ContainerExceptionInterface Error while retrieving the entry.
 	 *
-	 * @return int Entry.
+	 * @return float Entry.
 	 */
-	public function get(string $id): int
+	public function get(string $id): float
 	{
 		if (!$this->has($id)) {
 			return 0;

static/defaults.config.php

@@ -525,6 +525,14 @@ return [
 		// The authentication password for the redis database
 		'redis_password' => null,
 
+		// relay_deny_languages (Array)
+		// Array of languages that are rejected.
+		'relay_deny_languages' => [],
+
+		// relay_deny_undetected_language (Boolean)
+		// Deny undetected languages
+		'relay_deny_undetected_language' => false,
+
 		// session_handler (database|cache|native)
 		// Whether to use Cache to store session data or to use PHP native session storage.
 		'session_handler' => 'database',