Automatically Delete Posts older than 6 months ago

delete_posts.php

<?php 
// Please use this function carefully.
// Changes can't undone. Best regards from Serkan Algur :)
// Let the function begin
function delete_oldest_posts_salgur( ) {
    // We will collect posts from two years ago :)
    $args = array(
        'date_query' => array(
            array(
                'column' => 'post_date_gmt',
                'before' => '6 months ago',
            ),
        ),
        'posts_per_page' => -1,
        'post_type' => 'memorials'
    );
    // Get posts via WP_Query
    $query = new WP_Query( $args );
    //We are doing this for 'foreach'
    $posts = $query->get_posts();   

        foreach($posts as $post){
            echo $post->ID;
            $args = array(
                'posts_per_page' => -1,
                'order'          => 'ASC',
                'post_mime_type' => 'image', // only for images. Look at https://codex.wordpress.org/Function_Reference/get_children
                'post_parent'    => $post->ID,
                'post_type'      => 'attachment',
            );

            $attachments = get_children( $args );

            if ( $attachments ) {
                foreach ( $attachments as $attachment ) {
                    wp_delete_attachment($attachment->ID,true); //If You Want to trash post set true to false
                }
            }
            wp_delete_post($post->ID,true); //If You Want to trash post set true to false
        }

}

// Problem Solver Cron Job definition
function cron_delete_oldest_posts_salgur() {
    if ( ! wp_next_scheduled( 'delete_oldest_posts_salgur' ) ) {
        wp_schedule_event( current_time( 'timestamp' ), 'daily', 'delete_oldest_posts_salgur' );
    }
}
add_action( 'wp', 'cron_delete_oldest_posts_salgur' );

delete_posts_6months_interval.php

<?php 
// Please use this function carefully.
// Changes can't undone. Best regards from Serkan Algur :)
// Let the function begin
function delete_oldest_posts_salgur( ) {
    // We will collect posts from two years ago :)
    $args = array(
        'date_query' => array(
            array(
                'column' => 'post_date_gmt',
                'before' => '2 years ago',
            ),
        ),
        'posts_per_page' => -1,
        'post_type' => 'memorials'
    );
    // Get posts via WP_Query
    $query = new WP_Query( $args );
    //We are doing this for 'foreach'
    $posts = $query->get_posts();   

        foreach($posts as $post){
            echo $post->ID;
            $args = array(
                'posts_per_page' => -1,
                'order'          => 'ASC',
                'post_mime_type' => 'image', // only for images. Look at https://codex.wordpress.org/Function_Reference/get_children
                'post_parent'    => $post->ID,
                'post_type'      => 'attachment',
            );

            $attachments = get_children( $args );

            if ( $attachments ) {
                foreach ( $attachments as $attachment ) {
                    wp_delete_attachment($attachment->ID,true); //If You Want to trash post set true to false
                }
            }
            wp_delete_post($post->ID,true); //If You Want to trash post set true to false
        }

}


/**
PS. The problem is my brain. Totally forgot to change the function name in the filter. Copy/Paste is not a good thing... (Also typo...)
**/
add_filter( 'cron_schedules', 'cron_add_6months' );
function cron_add_6months( $schedules ) {
   // Adds Once six months to the existing schedules.
   $schedules['6_monthly'] = array(
       'interval' => 6 * MONTH_IN_SECONDS,
       'display' => __( 'Once six months' )
   );
   return $schedules;
}

// Problem Solver Cron Job definition
function cron_delete_oldest_posts_salgur() {
    if ( ! wp_next_scheduled( 'delete_oldest_posts_salgur' ) ) {
        wp_schedule_event( current_time( 'timestamp' ), '6_monthly', 'delete_oldest_posts_salgur' );
    }
}
add_action( 'wp', 'cron_delete_oldest_posts_salgur' );