Shows how to set up a switch where a user can delete their own record

pdb-record-delete-switch.php

<?php

/**
 * Plugin Name: PDB Record Delete Switch
 * Description: Gives users the ability to delete their own record
 * Version: 1.3
 */
class PDb_Record_Delete_Switch {

  /**
   * @var string name of the delete field
   * 
   * change this to match the field you are using to let the user delete their 
   * record. It should be a simple checkbox with a single value: yes
   */
  private $delete_switch_field_name = 'delete_record';

  /**
   * @var array the participant record
   */
  private $participant_record;
  
  /**
   * @var string name of the transient for saving the feedback message
   */
  const message = 'pdb-user_delete';

  /**
   * sets up the filter
   */
  public function __construct()
  {
    // this gives us the record after it has been updated
    add_action( 'pdb-after_submit_update', array($this, 'check_for_delete') );

    // register an event for this so that a confirmation email may be sent
    add_filter( 'pdb-register_global_event', array($this, 'register_events'), 30 );
    
    add_action( 'pdb-shortcode_set', array( $this, 'check_feedback' ) );
  }

  /**
   * checks the submission for the delete signal
   * 
   * @param array $participant_record the record values
   * 
   */
  public function check_for_delete( $participant_record )
  {
    if ( !is_admin() ) { // this can't be done from the admin
      
      if ( isset( $participant_record[$this->delete_switch_field_name] ) && $participant_record[$this->delete_switch_field_name] === 'yes' ) {
        $this->participant_record = $participant_record;
        $this->process_deletion();
      }
    }
  }

  /**
   * processes the record deletion
   * 
   * @global wpdb $wpdb
   */
  private function process_deletion()
  {
    global $wpdb;
    $sql = 'DELETE FROM ' . Participants_Db::$participants_table . ' WHERE `id` = %d';
    $success = $wpdb->query( $wpdb->prepare( $sql, $this->participant_record['id'] ) );

    // if we're debugging, dump the query to the log
    Participants_Db::debug_log( __METHOD__ . ' deleting a record with query: ' . $wpdb->last_query );

    if ( $success > 0 ) {
    
      Participants_Db::$session->clear('pdbid');
      PDb_Participant_Cache::clear_cache($this->participant_record['id']);
      /*
       * store the feedback message to show when the page refreshes
       */
      set_transient( self::message, 'Your record has been deleted.' );

      /**
       * trigger the deletion action
       *
       * @action pdb-record-delete-switch_record_deleted
       * @param array the record data from the deleted record
       */
      do_action( 'pdb-record-delete-switch_record_deleted', $this->participant_record );
    }
  }
  
  /**
   * registers the deletion event
   * 
   * @param array $evetns
   * @return array as $tag => $title
   */
  public function register_events( $events )
  {
    $events['pdb-record-delete-switch_record_deleted'] = __( 'User Record Delete' );
    return $events;
  }
  
  /**
   * checks for the feedback message
   * 
   * here, we look for the stored feedback message and show it if it is found
   * 
   * @param PDb_Record $record
   */
  public function check_feedback( $record )
  {
    $message = get_transient( self::message );
    
    if ( $message ) {
      
      add_filter( 'pdb-no_record_error_message_setting_value', function () use ( $message ) {
        return $message;
      }, 50 );
      
      add_filter( 'pdb-update_thanks_message', function () use ( $message ) {
        return $message;
      }, 50 );
      
      delete_transient( self::message );
    }
  }

}

new PDb_Record_Delete_Switch();