Smart Email Routing

Smart Email Routing

OM_Smart_Routing selects which SMTP connection to use per email send, with automatic failover.

How It Works

1. The primary connection is used for all outgoing mail
2. If the primary fails (wp_mail_failed hook), OMailer switches to the backup connection for the remainder of the send batch
3. After the batch, the primary is reinstated

Routing Rules (Advanced)

Beyond primary/backup, you can define rules that route mail based on:

• From address — route transactional mail through a different SMTP than marketing
• Subject prefix — e.g. [Order] → SES, everything else → Gmail
• Campaign tag — route campaigns tagged bulk through a dedicated IP

Rules are evaluated in order; the first match wins. Falls back to the primary connection if no rule matches.

PHP API

php// Force a specific connection for the next wp_mail() call
OM_SMTP::set_connection( 'conn_id' );

// After custom send, release the override
OM_SMTP::clear_connection();

// Get the connection ID that would be resolved for current context
$conn_id = OM_SMTP::resolve_connection();

Hooks

php// Fired when failover activates
add_action( 'om_smtp_failover', function( string $failed_conn_id, string $backup_conn_id ) {
    // log or alert
}, 10, 2 );

// Filter to override connection selection
add_filter( 'om_resolve_smtp_connection', function( string $conn_id, array $mail_data ): string {
    // inspect $mail_data['to'], $mail_data['subject'], etc.
    return $conn_id;
}, 10, 2 );