Subscriber DB Synch

Yes, it is possible to schedule a cron job to sync an external database with the ‘Newsletter’ plugin’s mailing list in WordPress. Here’s an overview of how you could achieve this:

Steps to Schedule a Cron Job for Synchronization:

1. Write a Custom PHP Script:

• Create a custom PHP script that connects to your external database, fetches the necessary data (e.g., subscriber emails), and updates the ‘Newsletter’ plugin’s subscriber list.
• The script would typically use wpdb, WordPress’s database class, to insert or update subscribers in the wp_newsletter table (or whatever prefix your tables use). Example of connecting to an external database and updating the Newsletter plugin’s table:

   // Connect to external database
   $external_db = new wpdb('user', 'password', 'external_database', 'host');

   // Fetch data from external database
   $subscribers = $external_db->get_results("SELECT email, first_name, last_name FROM external_subscribers");

   global $wpdb;
   foreach ($subscribers as $subscriber) {
       // Check if the email already exists
       $exists = $wpdb->get_var($wpdb->prepare("SELECT COUNT(*) FROM {$wpdb->prefix}newsletter WHERE email = %s", $subscriber->email));

       if ($exists) {
           // Update the existing subscriber
           $wpdb->update(
               "{$wpdb->prefix}newsletter",
               array(
                   'name' => $subscriber->first_name . ' ' . $subscriber->last_name,
               ),
               array('email' => $subscriber->email)
           );
       } else {
           // Insert a new subscriber
           $wpdb->insert(
               "{$wpdb->prefix}newsletter",
               array(
                   'email' => $subscriber->email,
                   'name' => $subscriber->first_name . ' ' . $subscriber->last_name,
                   'status' => 'C' // or another status code based on your needs
               )
           );
       }
   }

2. Schedule the Cron Job:

• You can use WordPress’s built-in wp_cron system to schedule this synchronization script. Example of setting up a custom cron event in your theme’s functions.php or a custom plugin:

   // Schedule an event if it's not already scheduled
   if (!wp_next_scheduled('newsletter_sync_cron_job')) {
       wp_schedule_event(time(), 'hourly', 'newsletter_sync_cron_job');
   }

   // Hook the function to our cron event
   add_action('newsletter_sync_cron_job', 'newsletter_sync_function');

   function newsletter_sync_function() {
       // Include your custom script or just include the logic directly here
       require_once 'path/to/your/sync-script.php';
   }

• The above example schedules the synchronization job to run every hour. You can adjust the frequency by changing 'hourly' to 'daily', 'twicedaily', or by creating a custom interval.

1. Alternative: Use wp-cli for Scheduling (Optional):

• If you prefer using the command line, you can schedule the PHP script using a system cron job and execute it via wp-cli:

   */30 * * * * /usr/bin/php /path/to/wordpress/wp-cli.phar eval-file /path/to/your/sync-script.php

This example schedules the script to run every 30 minutes.

Summary

By setting up a custom PHP script that interacts with the external database and using WordPress’s cron system (wp_cron) or a system cron job with wp-cli, you can automate the synchronization of your external database with the ‘Newsletter’ plugin’s mailing list. This setup ensures that your mailing list is regularly updated with the latest subscriber information from your external database.