Changeset 14075

Timestamp:

11/03/2024 07:16:26 PM (16 months ago)

Author:

espellcaste

Message:

Messages: Use a mysql subquery to insert the thread_id while inserting a new thread message.

By moving the thread_id insertion into a subquery, we can avoid race conditions where two messages are sent at the same time and both use the same thread_id.

Props imath and petersmithrestless.

Closes ​https://github.com/buddypress/buddypress/pull/399
Fixes #8544

File:

• trunk/src/bp-messages/classes/class-bp-messages-message.php (modified) (1 diff)

trunk/src/bp-messages/classes/class-bp-messages-message.php

@@ -140 +140 @@
         // If we have no thread_id then this is the first message of a new thread.
         if ( empty( $this->thread_id ) ) {
-            $this->thread_id = (int) $wpdb->get_var( "SELECT MAX(thread_id) FROM {$bp->messages->table_name_messages}" ) + 1;
-            $new_thread      = true;
+            $new_thread           = true;
+            $insert_message_query = $wpdb->prepare(
+                "INSERT INTO {$bp->messages->table_name_messages} "
+                . "( thread_id, sender_id, subject, message, date_sent ) "
+                . "VALUES ( " . "( SELECT IFNULL(MAX(m.thread_id), 0) FROM {$bp->messages->table_name_messages} m ) + 1, " . "%d, %s, %s, %s )",
+                $this->sender_id,
+                $this->subject,
+                $this->message,
+                $this->date_sent
+            );
+        } else { // Add a new message to an existing thread.
+            $insert_message_query = $wpdb->prepare(
+                "INSERT INTO {$bp->messages->table_name_messages} "
+                . "( thread_id, sender_id, subject, message, date_sent ) "
+                . "VALUES ( %d, %d, %s, %s, %s )",
+                $this->thread_id,
+                $this->sender_id,
+                $this->subject,
+                $this->message,
+                $this->date_sent
+            );
         }
 
         // First insert the message into the messages table.
-        if ( ! $wpdb->query( $wpdb->prepare( "INSERT INTO {$bp->messages->table_name_messages} ( thread_id, sender_id, subject, message, date_sent ) VALUES ( %d, %d, %s, %s, %s )", $this->thread_id, $this->sender_id, $this->subject, $this->message, $this->date_sent ) ) ) {
+        if ( ! $wpdb->query( $insert_message_query ) ) {
             return false;
         }
 
         $this->id = $wpdb->insert_id;
+
+        // For new threads fetch the thread_id that was generated during the insert query
+        if ( $new_thread ) {
+            $this->thread_id = (int) $wpdb->get_var( $wpdb->prepare( "SELECT thread_id FROM {$bp->messages->table_name_messages} WHERE id=%d", $this->id ) );
+        }
 
         $recipient_ids = array();