I recently needed to write a sync function that was triggered when a WooCommerce product is saved in the admin, i.e. added or updated. Strangely, there isn’t a WooCommerce-specific hook in the documentation. Since WooCommerce products are a WordPress custom post type, we should be able to make use of the save_post_{$post_type} action. When I tried the following:
add_action('save_post_product', 'mp_sync_on_product_save', 10, 3);
function mp_sync_on_product_save( $post_id, $post, $update ) {
$product = wc_get_product( $post_id );
// do something with this product
}
I found that the retrieved product contained the data from before the latest changes had been saved. But the hook runs after the post has been saved to the database – how could that be? Then it hit me – most of the WooCommerce product data is stored as post_meta. And the save_post hook runs before the post_meta is updated. So we need to use a hook which fires after the post_meta is updated or added. It turns out we have to hook on 2 separate actions in our case (added_post_meta, when the product post_meta is added; and updated_post_meta, when it is updated). We also want to use added_post_meta, rather than add_post_meta as this runs after the changes are saved to the database.
The post_meta hooks fire when any post_meta is changed, which means we need to check a few things:
- If multiple product fields have been updated, the hook will be triggered for each. Luckily, there is a meta_key called ‘_edit_lock’ which is always set when editing a post, so we can trigger our function when this is set.
- We also need to check that we are working with a product post_type.
Putting all this together gives us our modified hook which runs when all the WooCommerce product data has been saved to the database:
add_action( 'added_post_meta', 'mp_sync_on_product_save', 10, 4 );
add_action( 'updated_post_meta', 'mp_sync_on_product_save', 10, 4 );
function mp_sync_on_product_save( $meta_id, $post_id, $meta_key, $meta_value ) {
if ( $meta_key == '_edit_lock' ) { // we've been editing the post
if ( get_post_type( $post_id ) == 'product' ) { // we've been editing a product
$product = wc_get_product( $post_id );
// do something with this product
}
}
}
Thank you, you saved me a lot of time.
Hi Robin,
your post helped me alot. It was easier, than expected. 🙂
I’ve tested your code via a custom plugin and I’am wondering why my debug.log tells me, that the hook keeps firing.
Do you have a idea why that might be?
Kind regards,
Kevin
Hi Kevin. Can you post the line from your debug log?
Thank you very much for the prompt reply.
I am writing custom ‘error’ messages via error_log into the debug.log to see what’s happening. So the log only writes the message: ‘updated successfully’. It does so for about 1 minute and then stops.
Remember that when you save a product, you will be updating multiple post_meta. The hook will fire on each one. This is why we check the ‘_edit_lock’ key to make sure we only run our code once on each save/update.
sounds reasonable.
Thank you 🙂
I’m getting error “Maximum function nesting level ” when hook to the added_product_meta, when i go to the new product page.
Could you please help me? Regards.
It sounds like you’ve nested the function call – in other words, you’re calling the hook from within the function. This can happen if you update the product inside the mp_sync_on_product_save function, which will then call mp_sync_on_product_save, which will update the function etc. Can you post your code?
the hook `updated_post_meta` also trigger on product create, is there is hook only trigger on product update?
If you look at the code, the mp_sync_on_product_save function is triggered by 2 different actions: added_post_meta and updated_post_meta. So it runs when a product is added or updated.
If you only want it to run on updates, just remove the following line:
Is their any way i could show up all the products (newly added & modified) to show it on a page in the similar form of changelog. Simply, each time i add a product or modified a product it should log details and show up on a page. The above code seems it is creating logs but could you please tell, how to show it up. I hope there needs to be some shortcode to display.
Hi Jason, I think you’d need to use a different approach. Simply use some sort of Recently Added Products widget to display a list of recently modified or added products. Or just use the built-in WooCommerce shortcode: