WooCommerce - Overriding ajax add to cart not working - php

Question

I'm trying to override the ajax add to cart function of WooCoommerce and add this simple condition.
$base = true;
if($base){
return the default error just to test...
}else{
default functionality ...
}
I get the idea from here and simply add my condition to it just to test but it doesn't work.
function woocommerce_ajax_add_to_cart() {
global $woocommerce;
check_ajax_referer( 'add-to-cart', 'security' );
$product_id = apply_filters('woocommerce_add_to_cart_product_id', absint( $_POST['product_id'] ) );
$quantity = empty( $_POST['quantity'] ) ? 1 : apply_filters( 'woocommerce_stock_amount', $_POST['quantity'] );
$passed_validation = apply_filters('woocommerce_add_to_cart_validation', true, $product_id, $quantity );
$base = true;
if($base){//simple condition
header( 'Content-Type: application/json; charset=utf-8' );
// If there was an error adding to the cart, redirect to the product page to show any errors
$data = array(
'error' => true,
'product_url' => apply_filters('woocommerce_cart_redirect_after_error', get_permalink( $product_id ), $product_id)
);
$woocommerce->set_messages();
echo json_encode( $data );
}else{
if ( $passed_validation && $woocommerce->cart->add_to_cart( $product_id, $quantity ) ) {
do_action( 'woocommerce_ajax_added_to_cart', $product_id );
if ( get_option( 'woocommerce_cart_redirect_after_add' ) == 'yes' ) {
woocommerce_add_to_cart_message( $product_id );
$woocommerce->set_messages();
}
// Return fragments
woocommerce_get_refreshed_fragments();
} else {
header( 'Content-Type: application/json; charset=utf-8' );
// If there was an error adding to the cart, redirect to the product page to show any errors
$data = array(
'error' => true,
'product_url' => apply_filters('woocommerce_cart_redirect_after_error', get_permalink( $product_id ), $product_id)
);
$woocommerce->set_messages();
echo json_encode( $data );
}
}
die();
}
add_action('wp_ajax_woocommerce_add_to_cart', 'woocommerce_ajax_add_to_cart');
add_action('wp_ajax_nopriv_woocommerce_add_to_cart', 'woocommerce_ajax_add_to_cart');
Am I missing something?

Answer 1

Yes, you missed the whole thing. Instead of wp_ajax_woocommerce_add_to_cart the action you need is woocommerce_add_to_cart and you don't need the wp_ajax_nopriv_woocommerce_add_to_cart action at all.
Instead of that source, you should be taking the idea from here. It is located on woocommerce/includes/class-wc-ajax.php.
Take note of self::get_refreshed_fragments(), used WC_AJAX::get_refreshed_fragments() instead.
Overall, your code should be:
function woocommerce_ajax_add_to_cart() {
ob_start();
// phpcs:disable WordPress.Security.NonceVerification.Missing
if ( !isset( $_POST[ 'product_id' ] ) ) {
return;
}
$product_id = apply_filters( 'woocommerce_add_to_cart_product_id', absint( $_POST[ 'product_id' ] ) );
$product = wc_get_product( $product_id );
$quantity = empty( $_POST[ 'quantity' ] ) ? 1 : wc_stock_amount( wp_unslash( $_POST[ 'quantity' ] ) );
$passed_validation = apply_filters( 'woocommerce_add_to_cart_validation', true, $product_id, $quantity );
$product_status = get_post_status( $product_id );
$variation_id = 0;
$variation = array();
if ( $product && 'variation' === $product->get_type() ) {
$variation_id = $product_id;
$product_id = $product->get_parent_id();
$variation = $product->get_variation_attributes();
}
$base = true;
if ( $base ) { /** Your condition here **/
// If there was an error adding to the cart, redirect to the product page to show any errors.
$data = array(
'error' => true,
'product_url' => apply_filters( 'woocommerce_cart_redirect_after_error', get_permalink( $product_id ), $product_id ),
);
wp_send_json( $data );
} else {
if ( $passed_validation && false !== WC()->cart->add_to_cart( $product_id, $quantity, $variation_id, $variation ) && 'publish' === $product_status ) {
do_action( 'woocommerce_ajax_added_to_cart', $product_id );
if ( 'yes' === get_option( 'woocommerce_cart_redirect_after_add' ) ) {
wc_add_to_cart_message( array( $product_id => $quantity ), true );
}
WC_AJAX::get_refreshed_fragments();
} else {
// If there was an error adding to the cart, redirect to the product page to show any errors.
$data = array(
'error' => true,
'product_url' => apply_filters( 'woocommerce_cart_redirect_after_error', get_permalink( $product_id ), $product_id ),
);
wp_send_json( $data );
}
}
// phpcs:enable
}
add_action( 'woocommerce_add_to_cart', 'woocommerce_ajax_add_to_cart' );
EDIT: You may be in a known issue (also here) where the action woocommerce_add_to_cart is being called multiple times because of the function WC()->cart->add_to_cart(...).
Base on this source, you can solve it by adding conditional statement so that the WC()->cart->add_to_cart(...) won't cause the issue.
I don't know what you are trying to achieve, but base on your code it looks like you just want to add another condition before adding the products into the cart.
In that case, you could do the following.
function woocommerce_ajax_add_to_cart() {
ob_start();
if ( !isset( $_POST[ 'product_id' ] ) ) {
return;
}
$found = false;
$base = true;
if ( $base ) { /** Your condition here **/
// If there was an error adding to the cart, redirect to the product page to show any errors.
$data = array(
'error' => true,
'product_url' => apply_filters( 'woocommerce_cart_redirect_after_error', get_permalink( $product_id ), $product_id ),
);
wp_send_json( $data );
}else{
if ( sizeof( WC()->cart->get_cart() ) > 0 ) { //check if product already in cart
foreach ( WC()->cart->get_cart() as $cart_item_key => $values ) {
$_product = $values['data'];
if ( $_product->id == $product_id )
$found = true;
}
if ( ! $found ){ // if product not found, add it
WC()->cart->add_to_cart( $product_id, $quantity, $variation_id, $variation );
}
} else {
WC()->cart->add_to_cart( $product_id, $quantity, $variation_id, $variation ); // if no products in cart, add it
}
}
}
add_action( 'woocommerce_add_to_cart', 'woocommerce_ajax_add_to_cart' );
OR
function woocommerce_ajax_add_to_cart() {
ob_start();
if ( !isset( $_POST[ 'product_id' ] ) ) {
return;
}
$found = false;
$base = true;
if ( sizeof( WC()->cart->get_cart() ) > 0 ) { //check if product already in cart
foreach ( WC()->cart->get_cart() as $cart_item_key => $values ) {
$_product = $values['data'];
if ( $_product->id == $product_id )
$found = true;
}
if ( ! $found ){ // if product not found, add it
if ( $base ) { /** Your condition here **/
$data = array(
'error' => true,
'product_url' => apply_filters( 'woocommerce_cart_redirect_after_error', get_permalink( $product_id ), $product_id ),
);
wp_send_json( $data );
}else{
WC()->cart->add_to_cart( $product_id, $quantity, $variation_id, $variation );
}
}
} else {
WC()->cart->add_to_cart( $product_id, $quantity, $variation_id, $variation ); // if no products in cart, add it
}
}
add_action( 'woocommerce_add_to_cart', 'woocommerce_ajax_add_to_cart' );