Custom meta box data not saving

Question

I created this meta box for my custom theme. I thought I followed all the guidelines, but I'm hitting a wall. The meta box and all fields are showing, but when I update, the data is not saved.

Meta box addition:

function drw_events_metabox(){
    add_meta_box('events_info', 'EVENT INFO', 'drw_evenet_info_clbk', 'drw-events', 'side', 'high');
}

function drw_evenet_info_clbk($post){
    wp_nonce_field('drw_event_info', 'drw_event_info_nonce');
    $datevalue = get_post_meta( $post->ID, '_event_date_valkey', true);
    $starttimevalue = get_post_meta( $post->ID, '_event_time_valkey', true);
    $endtimevalue = get_post_meta( $post->ID, '_event_endtime_valkey', true);
    $covervalue = get_post_meta( $post->ID, '_event_cover_valkey', true);
    $freeEvent = get_post_meta( $post->ID, '_event_free_valkey', true);
    $stdTicketLink = get_post_meta( $post->ID, '_event_stdticket_valkey', true);
    $customTicketLink = get_post_meta( $post->ID, '_event_customTicketLink_valkey', true);
    $eventCancelled = get_post_meta( $post->ID, '_event_cancel_valkey', true);


    //event date
    echo'<br><label for="drw_event_date_field">Event Date </label>';
    echo '<input type="date" id="drw_event_date_field" name="drw_event_date_field" value="'.esc_attr($datevalue).'" required/><br><br><hr><br>';

    //event time
    echo'<label for="drw_event_time_field">Event start time </label>';
    echo '<input type="time" id="drw_event_time_field" name="drw_event_time_field" value="'.esc_attr($starttimevalue).'" required/><br><br>';


    echo'<label for="drw_event_endtime_field">Event end time </label>';
    echo '<input type="time" id="drw_event_endtime_field" name="drw_event_endtime_field" value="'.esc_attr($endtimevalue).'" required/><br><br><hr><br>';

    //event price
    echo'<label for="drw_event_free_field">Event is free </label>';
    echo'<input type="checkbox" id="drw_event_free_field" name="drw_event_free_field" value="'.esc_attr($freeEvent).'" checked/><br><br>';

    echo'<label for="drw_event_cover_field">Event cover $ </label>';
    echo '<input type="number" id="drw_event_cover_field" name="drw_event_cover_field" value="'.esc_attr($covervalue).'" size="2"/><br><br><hr><br>';


    //event ticket
    echo '<h2><strong><em>Choose a ticket purchase link</em></strong></h2><br>';
    echo'<label for="drw_event_stdtktlink_field">Default link </label>';
    echo '<input type="checkbox" id="drw_event_stdtktlink_field" name="drw_stdtktlink_field" value="#" checked/><br><br>';
    echo'<label for="drw_event_customTicketLink_field">Custom link </label>';
    echo '<input type="text" id="drw_event_customTicketLink_field" name="drw_customTicketLink_field" value="'.esc_attr($customTicketLink).'"/><br><br><hr><br>';

    //event cancellation
    echo '<h2><strong><em>**Use only for event cancellation!</em></strong></h2><br>';
    echo'<label for="drw_event_cancelled_field">Event Cancelled </label>';
    echo '<input type="checkbox" id="drw_event_cancelled_field" name="drw_event_cancelled_field" value="'.esc_attr($eventCancelled).'"/><br><br><hr><br>';

}

add_action('add_meta_boxes', 'drw_events_metabox');

Saving meta box data:

function save_drw_events_metabox_data( $post_id ) {

    if( ! isset( $_POST['drw_event_info_nonce'] ) ){
        return;
    }

    if( ! wp_verify_nonce( $_POST['drw_event_info_nonce'], 'save_drw_events_metabox_data') ) {
        return;
    }

    if( defined('DOING_AUTOSAVE') && DOING_AUTOSAVE ){
        return;
    }

    if( ! current_user_can( 'edit_post', $post_id ) ) {
        return;
    }


    $event_date = sanitize_text_field( $_POST['drw_event_date_field'] );
    $event_time = sanitize_text_field( $_POST['drw_event_time_field'] );
    $event_entime = sanitize_text_field( $_POST['drw_event_endtime_field'] );
    $event_free = sanitize_text_field( $_POST['drw_event_free_field'] );
    $event_cover = sanitize_text_field( $_POST['drw_event_cover_field'] );
    $event_linkdef = sanitize_text_field( $_POST['drw_stdtktlink_field'] );
    $event_tix = sanitize_text_field( $_POST['drw_customTicketLink_field'] );
    $event_cancel = sanitize_text_field( $_POST['drw_event_cancelled_field'] );


    if( ! isset( $_POST['drw_event_date_field'] ) ) {
        return;  
        update_post_meta($post_id, '_event_date_valkey', $event_date);
    }

    if( ! isset( $_POST['drw_event_time_field'] ) ) {
        return;
        update_post_meta($post_id, '_event_time_valkey', $event_time);
    }

    if( ! isset( $_POST['drw_event_endtime_field'] ) ) {
        return;
        update_post_meta($post_id, '_event_endtime_valkey', $event_entime);
    }

    if( ! isset( $_POST['drw_event_cover_field'] ) ) {
        return;
        update_post_meta($post_id, '_event_cover_valkey', $event_cover);
    }


    if( ! isset( $_POST['drw_event_free_field'] ) ) {
        return;   
        update_post_meta($post_id, '_event_free_valkey', true);
    } else {
        update_post_meta( $post_id, '_event_free_valkey', FALSE );
    }


    if( ! isset( $_POST['drw_stdtktlink_field'] ) ) {
        return;
        update_post_meta($post_id, '_event_stdticket_valkey', $event_linkdef);
    }

    if( ! isset( $_POST['drw_customTicketLink_field'] ) ) {
        return;
        update_post_meta($post_id, '_event_customTicketLink_valkey', $event_tix);
    }


    if( ! isset( $_POST['drw_event_cancelled_field'] ) ) {
        return;
        update_post_meta($post_id, '_event_cancel_valkey', true);
    } else {
        update_post_meta( $post_id, '_event_cancel_valkey', FALSE );
    }

}

add_action( 'save_post', 'save_drw_events_metabox_data');

Really I have no idea what I am missing at this point. All of my research is saying that the CODE is right, but still no data is saved!

Please help.

Answer 1

To follow-up on the comment made by @mmm, you've got a number of statements like:

if ( ! isset ($_POST['drw_event_date_field'] ) ) {
    return ;
update_post_meta ($post_id, '_event_date_valkey', $event_date) ;
}

Notice that you are wrapping your calls to update_post_meta() inside the !isset() conditionals.

What you want is:

if ( ! isset ($_POST['drw_event_date_field'] ) ) {
    return ;
}
update_post_meta ($post_id, '_event_date_valkey', $event_date) ;

Also, even when you correct the logic as above, you might still fail to save some values, e.g., if "drw_event_date_field" is not set you will not save any values, even those that are set...which is probably not what you want.

You'd probably be better off with logic such as:

$fields = array (
    '_event_time_valkey' => 'drw_event_date_field',
    '_event_endtime_valkey' => 'drw_event_time_field',
    '_event_endtime_valkey' => 'drw_event_endtime_field',
    '_event_free_valkey' => 'drw_event_free_field',
    '_event_cover_valkey' => 'drw_event_cover_field',
    '_event_stdticket_valkey' => 'drw_stdtktlink_field',
    '_event_customTicketLink_valkey' => 'drw_customTicketLink_field',
    '_event_cancel_valkey' => 'drw_event_cancelled_field',
    ) ;

foreach ($fields as $meta_key => $field) {
    if (!isset ($_POST[$field])) {
        if ($field == 'drw_event_cancelled_field') {
            update_post_meta ($post_id, $meta_key, false) ;
            }

        continue ;
        }

    $meta_val = sanitize_text_field ($_POST[$field]) ;
    update_post_meta ($post_id, $meta_key, $meta_val) ;
    }