[FIX] form crm saving lost concurrent update

wordpress/wp-content/themes/les-verts/lib/form/include/CrmSaver.php

@@ -119,9 +119,13 @@ public static function save_to_crm( bool $force = false ) {
 				Util::debug_log( "submissionId={$item->get_submission_id()} msg=No data. Discarding entry." );
 
 				// remove item from queue
-				$queue->filter( static function ( $q_item ) use ( $item ) {
-					return $item->get_submission_id() !== $q_item->get_submission_id();
-				} );
+				try {
+					$queue->filter( static function ( $q_item ) use ( $item ) {
+						return $item->get_submission_id() !== $q_item->get_submission_id();
+					} );
+				} catch ( Exception $e ) {
+					// do nothing, well remove it the next time
+				}
 			}
 
 			// if we have exceeded the max attempts,
@@ -156,15 +160,19 @@ public static function save_to_crm( bool $force = false ) {
 			// on success: remove item from queue
 			Util::debug_log( "submissionId={$item->get_submission_id()} msg=Saved successfully. CRM id: $crm_id" );
 
-			$queue->filter( static function ( $q_item ) use ( $item ) {
-				if ( $item->get_submission_id() === $q_item->get_submission_id() ) {
-					Util::debug_log( "submissionId={$item->get_submission_id()} msg=Remove from queue." );
+			try {
+				$queue->filter( static function ( $q_item ) use ( $item ) {
+					if ( $item->get_submission_id() === $q_item->get_submission_id() ) {
+						Util::debug_log( "submissionId={$item->get_submission_id()} msg=Remove from queue." );
 
-					return false; // remove from queue
-				}
+						return false; // remove from queue
+					}
 
-				return true;
-			} );
+					return true;
+				} );
+			} catch ( Exception $e ) {
+				// do nothing, we'll remove it the next time
+			}
 		}
 	}
 
@@ -270,6 +278,8 @@ private static function send_permanent_error_notification( $submission, $err_mes
 
 	/**
 	 * Add the submission to saving queue
+	 *
+	 * @throws Exception
 	 */
 	public function queue() {
 		$data = $this->get_data();

wordpress/wp-content/themes/les-verts/lib/form/include/Mailer.php

@@ -55,6 +55,8 @@ public static function get_queue(): QueueDao {
 
 	/**
 	 * Add the mails for the submission to the sending queue
+	 *
+	 * @throws Exception
 	 */
 	public function queue_mails() {
 		$this->queue_confirmation();
@@ -69,6 +71,8 @@ public function queue_mails() {
 
 	/**
 	 * Queue the confirmation mail, if confirmation is enabled and we have a destination address
+	 *
+	 * @throws Exception
 	 */
 	private function queue_confirmation() {
 		$to = $this->submission->meta_get_linked_email();
@@ -91,6 +95,8 @@ private function queue_confirmation() {
 
 	/**
 	 * Queue the notification mail, if notification is enabled
+	 *
+	 * @throws Exception
 	 */
 	private function queue_notification() {
 		if ( $this->form->has_notification() ) {
@@ -176,8 +182,14 @@ public static function send_mails() {
 		$queue = self::get_queue();
 		$error = 0;
 
-		/** @var Mail $mail */
-		$mail = $queue->pop();
+		try {
+			/** @var Mail $mail */
+			$mail = $queue->pop();
+		} catch ( Exception $e ) {
+			// just wait for the next run
+			return;
+		}
+
 		while ( ! empty( $mail ) ) {
 			$sent = $mail->send();
 
@@ -186,7 +198,11 @@ public static function send_mails() {
 
 				// requeue mail on error if number of retries is not exceeded
 				if ( $mail->get_sending_attempts() < self::SENDING_RETRIES ) {
-					$queue->push( $mail );
+					try {
+						$queue->push( $mail );
+					} catch ( Exception $e ) {
+						self::send_error_notification( $mail, $e );
+					}
 					$error ++;
 				}
 
@@ -196,7 +212,45 @@ public static function send_mails() {
 				}
 			}
 
-			$mail = $queue->pop();
+			try {
+				$mail = $queue->pop();
+			} catch ( Exception $e ) {
+				// just wait for the next run
+				return;
+			}
 		}
 	}
+
+	private static function send_error_notification( Mail $mail, Exception $e ) {
+		$domain = Util::get_domain();
+
+		$subject = sprintf(
+			__( '%s: ERROR while sending mail', THEME_DOMAIN ),
+			$domain
+		);
+
+		$message = sprintf(
+			__(
+				"Hi Admin of %s\n\n" .
+				"There was an ERROR while sending the following mail and we were unable to save it back to the sending queue." .
+				"YOU MUST SEND IT MANUALLY. The mail:\n\n---\n\n" .
+				"to: %s\n" .
+				"subject: %s\n" .
+				"body: %s\n\n---\n\n" .
+				"More details in the error message below.\n\n" .
+				"Have a nice day.\n" .
+				"Your Website - %s\n\n" .
+				"Error message:\n%s",
+				THEME_DOMAIN
+			),
+			$domain,
+			$mail->get_to(),
+			$mail->get_subject(),
+			$mail->get_body(),
+			$domain,
+			$e->getMessage(),
+		);
+
+		Util::send_mail_to_admin( $subject, $message );
+	}
 }

wordpress/wp-content/themes/les-verts/lib/form/include/QueueDao.php

@@ -3,12 +3,22 @@
 
 namespace SUPT;
 
+use Exception;
+
 /**
  * Data queue. Based on WordPress' options api.
  *
  * @package SUPT
  */
 class QueueDao {
+	/**
+	 * Time to wait to acquire a lock.
+	 *
+	 * Should be long enough to survive the sending time of a mail, but
+	 * be short enough to not run into PHPs max_execution_time timeout.
+	 */
+	const LOCK_ACQUIRE_TIMEOUT_SECONDS = 15;
+
 	/**
 	 * The key under witch the queue is stored
 	 *
@@ -29,6 +39,8 @@ public function __construct( $key ) {
 	 * Add item to the end of the queue
 	 *
 	 * @param mixed $item
+	 *
+	 * @throws Exception
 	 */
 	public function push( $item ) {
 		$this->lock();
@@ -44,6 +56,8 @@ public function push( $item ) {
 	 * Return the first item from the queue and remove it
 	 *
 	 * @return mixed|null null if queue is empty
+	 *
+	 * @throws Exception
 	 */
 	public function pop() {
 		$this->lock();
@@ -102,6 +116,8 @@ public function clear() {
 	 * Remove item with given index from queue
 	 *
 	 * @param int $index
+	 *
+	 * @throws Exception
 	 */
 	public function remove( int $index ) {
 		$this->lock();
@@ -120,6 +136,8 @@ public function remove( int $index ) {
 	 *                           the item, true will keep it.
 	 *
 	 * @return int The number of elements removed
+	 *
+	 * @throws Exception
 	 */
 	public function filter( callable $callback ): int {
 		$this->lock();
@@ -134,13 +152,34 @@ public function filter( callable $callback ): int {
 		return $lenBefore - $lenAfter;
 	}
 
+	/**
+	 * @throws Exception
+	 */
 	private function lock() {
 		global $wpdb;
-		$wpdb->query( "LOCK TABLES $wpdb->options WRITE" );
+		$lock    = $this->get_lock_name();
+		$timeout = self::LOCK_ACQUIRE_TIMEOUT_SECONDS;
+		$result  = $wpdb->get_var( "SELECT GET_LOCK('$lock', $timeout);" );
+		if ( $result !== '1' ) {
+			throw new Exception( "Failed to acquire DB lock \"$lock\": $result" );
+		}
 	}
 
+	/**
+	 * @throws Exception
+	 */
 	private function unlock() {
 		global $wpdb;
-		$wpdb->query( "UNLOCK TABLES" );
+		$lock   = $this->get_lock_name();
+		$result = $wpdb->get_var( "SELECT RELEASE_LOCK('$lock');" );
+		if ( $result !== '1' ) {
+			throw new Exception( "Failed to release DB lock \"$lock\": $result" );
+		}
+	}
+
+	private function get_lock_name(): string {
+		global $wpdb;
+
+		return DB_NAME . '.' . $wpdb->postmeta . '.' . $this->key;
 	}
 }

wordpress/wp-content/themes/les-verts/lib/form/include/cli/FormCrmCommand.php

@@ -3,6 +3,7 @@
 
 namespace SUPT;
 
+use Exception;
 use WP_CLI;
 use function WP_CLI\Utils\format_items;
 
@@ -158,6 +159,7 @@ public function store( $args, $assoc_args ) {
 	 *
 	 * [--all]
 	 * : Delete all crm data in the queue.
+	 * @throws Exception
 	 */
 	public function delete( $args, $assoc_args ) {
 		$queue = CrmSaver::get_queue();
@@ -173,7 +175,11 @@ public function delete( $args, $assoc_args ) {
 		/** @var CrmQueueItem $item */
 		foreach ( $queue->get_all() as $index => $item ) {
 			if ( $id === $item->get_submission_id() ) {
-				$queue->remove( $index );
+				try {
+					$queue->remove( $index );
+				} catch ( Exception $e ) {
+					WP_CLI::error( "Failed to delete item. {$e->getMessage()}" );
+				}
 
 				return;
 			}

wordpress/wp-content/themes/les-verts/lib/form/include/cli/FormMailCommand.php

@@ -3,6 +3,7 @@
 
 namespace SUPT;
 
+use Exception;
 use WP_CLI;
 use function WP_CLI\Utils\format_items;
 
@@ -134,7 +135,11 @@ public function delete( $args, $assoc_args ) {
 			return;
 		}
 
-		$queue->remove( absint( $args[0] ) );
+		try {
+			$queue->remove( absint( $args[0] ) );
+		} catch ( Exception $e ) {
+			WP_CLI::error( "Failed to delete item. {$e->getMessage()}" );
+		}
 	}
 }