Save Woocomerce discount as percentage to database

Question

I'm not sure if this is the best method to go about this, but here is my problem:

I want to display the discount percentage on an item (i.e. Sales Price - Regular Price / Regular Price * 100)

Woocommerce doesn't natively store that info, it only stores sales price and regular price.

I'm looking to display this in Revolution Slider, so I want to have it as meta values.

I'm not sure if this is the best approach.

Further, I wouldn't be sure where to start with trying to create a new entry in wp_postmeta.

Would I be looking at creating a small plugin or do you think there's a simpler way to achieve what I want?

Answer 1

With thanks to stillatmylinux for the steer.

Here's the code I used in the end should anyone need something similar

// Woocommerce Percentage Saved

function percentager_shortcode($atts)
{
// override default attributes with user attributes
$percentager_atts = shortcode_atts([
                                 'reg' => '500',
                                 'sale' => '200'
                             ], $atts);
                             $added_up = round( ( ( $percentager_atts['reg'] - $percentager_atts['sale'] ) / $percentager_atts['reg'] ) * 100 );

// start output
$o = '';

// Words
$o .=  esc_html__($added_up, 'percentager') . '% Off';

// return output
return $o;
}

function percentager_shortcodes_init()
{
add_shortcode('percentager', 'percentager_shortcode');
}

add_action('init', 'percentager_shortcodes_init');

Then the shortcode used in Revolution slider:

[percentager reg="{{meta:_regular_price}}" sale="{{meta:_sale_price}}"]