Update / Save Post Meta - PHP - Wordpress - php

Question

I'm using a plugin on Woocommerce that adds a new metabox with editable quantity number fields onto the admin back-end.
My theme allows for front-end product posting and so I want to add bring some of these fields to the front-end.
I have managed to add the fields in my template file by using :
<?php
$min = get_post_meta( $post->ID, '_wpbo_minimum', true );
$max = get_post_meta( $post->ID, '_wpbo_maximum', true );
?>
<label for="_wpbo_minimum">Minimum Quantity</label>
<input type="number" name="_wpbo_minimum" value="<?php echo $min; ?>" />
<label for="_wpbo_maximum">Maximum Quantity</label>
<input type="number" name="_wpbo_maximum" value="<?php echo $max; ?>" />
Both fields are showing on my front-end product edit form and getting their values from the backend if these were previously filled in.
But now I am struggling with updating and saving the fields with updated values
from front-end or saving new values from front-end if these values were not previously filled in.
I spent hours finding some tutorial on this, I think I should be concentrating on the following code :
update_post_meta($post->ID, '_wpbo_minimum', $_POST['_wpbo_minimum']);
update_post_meta($post->ID, '_wpbo_maximum', $_POST['_wpbo_maximum']);
But I can't figure out if this is correct and where should this code be placed in order to save or update my fields.
I tried placing a function into my functions.php file that looks like this :
/* Update Minimum Qty field */
add_action('save_post', 'save_min_qty');
function save_min_qty($post_id)
{
if(get_post_type($post_id) != "VA_LISTING_PTYPE")
return;
$min = get_post_meta( $post->ID, '_wpbo_minimum', true );
if ( isset( $_POST['_wpbo_minimum'] )) {
$min = $_POST['_wpbo_minimum'];
}
if( isset( $_POST['_wpbo_minimum'] )) {
if ( $min != 0 ) {
$min = wpbo_validate_number( $min );
}
update_post_meta(
$post_id,
'_wpbo_minimum',
strip_tags( $min )
);
}
But this just doesn't seem to be the winner.
Would you be please able to point me to the right direction ?
Below is the code from the actual original plugin that creates metabox in the back-end, I am not sure if it's any relevant to what I need to do in front-end and what part of this and where should I be using it :
<?php
if ( ! class_exists( 'IPQ_Quantity_Meta_Boxes' ) ) :
class IPQ_Quantity_Meta_Boxes {
public function __construct() {
add_action( 'save_post', array( $this, 'save_quantity_meta_data' ) );
}
/* Handle Saving Meta Box Data */
public function save_quantity_meta_data( $post_id ) {
// Validate Post Type
if ( ! isset( $_POST['post_type'] ) or $_POST['post_type'] !== 'product' ) {
return;
}
// Validate User
if ( !current_user_can( 'edit_post', $post_id ) ) {
return;
}
// Verify Nonce
if ( ! isset( $_POST["_wpbo_product_rule_nonce"] ) or ! wp_verify_nonce( $_POST["_wpbo_product_rule_nonce"], plugin_basename( __FILE__ ) ) ) {
return;
}
// Update Rule Meta Values
if ( isset( $_POST['_wpbo_minimum'] )) {
$min = $_POST['_wpbo_minimum'];
}
if( isset( $_POST['_wpbo_minimum'] )) {
if ( $min != 0 ) {
$min = wpbo_validate_number( $min );
}
update_post_meta(
$post_id,
'_wpbo_minimum',
strip_tags( $min )
);
}
/* Make sure Max > Min */
if( isset( $_POST['_wpbo_maximum'] )) {
$max = $_POST['_wpbo_maximum'];
if ( isset( $min ) and $max < $min and $max != 0 ) {
$max = $min;
}
update_post_meta(
$post_id,
'_wpbo_maximum',
strip_tags( wpbo_validate_number( $max ) )
);
}
}
}
endif;

Answer 1

Everything is correct except that you are checking for the wrong post_type - it should be "product" not "VA_LISTING_PTYPE". Your function hooked to save_post is returning early because the post type is not correct.
Incorrect
if(get_post_type($post_id) != "VA_LISTING_PTYPE")
return;
Correct
if (get_post_type($post_id) != "product"){
// bail early if we aren't updating a WooCommerce Product
return;
}
You can see the same check in the plugin you are extending here:
https://github.com/wpbackoffice/woocommerce-incremental-product-quantities/blob/master/includes/class-ipq-product-meta-box.php#L222