Woocommerce deletes cart before adding new product

Question

I have a pretty basic problem , I guess people working with woocommerce and wordpress would know how to solve this.

I have a customizable product the customer creates on a page, and then are able to add it to the cart.

The product and the add to cart button works fine so to say.

It add's the product - BUT it clears the cart before adding the newly customized product. Why does it do that ? And how can I avoid it - so it just add's another one to the cart before emptying the current one.

My add to cart button:

$woocommerce->cart->add_to_cart( $product_ID, $quantity=1 )

My product creation:

function customcart() {

  if (isset($_POST["addcustomcarts"])) {

    global $woocommerce;
    $my_post = array(
      'post_title'    => 'Design selv skilt',
      'post_content'  => '<div class="col-md-12">Dette er et design selv skilt, tjek egenskaber på produktet for at se hvad kunden har bestilt.</div>',
      'post_status'   => 'publish',
      'post_author'   => 1,
      'post_type'     => 'product'
    );

    // Insert the post into the database
    $product_ID = wp_insert_post( $my_post );

    $filteredData=substr($_POST['img_val'], strpos($_POST['img_val'], ",")+1);

    //Decode the string
    $unencodedData=base64_decode($filteredData);

    //Save the image
    file_put_contents('img' . $product_ID . '.png', $unencodedData);

    if ( $product_ID ){
      wp_set_object_terms( $product_ID, 'design-selv-skilte', 'product_cat' );
      add_post_meta($product_ID, '_regular_price', $_POST["priceInput"] );
      add_post_meta($product_ID, '_price', $_POST["priceInput"] );
      add_post_meta($product_ID, '_stock_status', 'instock' );
      //add_post_meta($product_ID, '_manage_stock', 'yes' );    
      //add_post_meta($product_ID, '_stock', '10' ); 
      add_post_meta($product_ID, '_sku', 'designselvskilt-' . $product_ID );   
      add_post_meta($product_ID, '_visibility', 'hidden' );
      add_post_meta($product_ID, 'tekst-paa-linje-1', $_POST["textInput"] );
      add_post_meta($product_ID, 'tekst-paa-linje-2', $_POST["text2Input"] );
      add_post_meta($product_ID, 'stoerrelse', $_POST["størrelseInput"] );
      add_post_meta($product_ID, 'form', $_POST["formInput"] );
      add_post_meta($product_ID, 'farve', $_POST["farveInput"] );
      add_post_meta($product_ID, 'type-skilt', $_POST["typeInput"] );
      add_post_meta($product_ID, 'fastgoering', $_POST["fastgøringInput"] );
      add_post_meta($product_ID, 'font', $_POST["fontInput"] );
      add_post_meta($product_ID, 'linje-1-font-size', $_POST["fontSizeLine1Input"] );
      add_post_meta($product_ID, 'linje-2-font-size', $_POST["fontSizeLine2Input"] );
      add_post_meta($product_ID, 'product_image_gallery', $_POST["img_val"]);
      add_post_meta($product_ID, 'product_image_url', 'img' . $product_ID . '.png');  
      require_once(ABSPATH . 'wp-admin/includes/media.php');
      require_once(ABSPATH . 'wp-admin/includes/file.php');
      require_once(ABSPATH . 'wp-admin/includes/image.php');
      $home = home_url();
      $url = $home . '/img' . $product_ID . '.png';
      $post_id = $product_ID;
      $desc = $_POST["textInput"];
      $image = media_sideload_image($url, $post_id, $desc, src );

              function getImageId( $image ) {
            // Split the $url into two parts with the wp-content directory as the separator
            $parsed_url  = explode( parse_url( WP_CONTENT_URL, PHP_URL_PATH ), $image );

            // Get the host of the current site and the host of the $url, ignoring www
            $this_host = str_ireplace( 'www.', '', parse_url( home_url(), PHP_URL_HOST ) );
            $file_host = str_ireplace( 'www.', '', parse_url( $image, PHP_URL_HOST ) );

            // Return nothing if there aren't any $url parts or if the current host and $url host do not match
            if ( ! isset( $parsed_url[1] ) || empty( $parsed_url[1] ) || ( $this_host != $file_host ) ) {
                return;
            }

            // Now we're going to quickly search the DB for any attachment GUID with a partial path match
            // Example: /uploads/2013/05/test-image.jpg
            global $wpdb;

            $attachment = $wpdb->get_col( $wpdb->prepare( "SELECT ID FROM {$wpdb->prefix}posts WHERE guid RLIKE %s;", $parsed_url[1] ) );

            // Returns null if no attachment is found
            return $attachment[0];
        }    

      set_post_thumbnail($post_id, getImageId( $image ));    

      $woocommerce->cart->add_to_cart( $product_ID, $quantity=1 );

       wp_redirect( '/kurv' ); exit;

    }
  }

}

Answer 1

There is a filter for that

add_filter( 'woocommerce_add_cart_item_data', 'wdm_empty_cart', 10,  3);
function wdm_empty_cart( $cart_item_data, $product_id, $variation_id ) 
{
    global $woocommerce;
    $woocommerce->cart->empty_cart();

    // Do nothing with the data and return
    return $cart_item_data;
}

Answer 2

So here is the solution for this question, Matthew was pointing me in the right direction concerning the cart session but the code that worked for me was this :

So before adding product to cart I had to retrieve the current cart session.

$woocommerce->cart->get_cart_from_session();
$woocommerce->cart->add_to_cart($product_ID);

Answer 3

It seems that you are not the only one to find that the cart needs to be initialized first to get consistent and expected behaviours from it:

• How to properly initialize Woocommerce Cart

I would suggest that you consider getting in something like:

$woocommerce->session->set_customer_session_cookie(true);

To get things going so that you are not making and setting a new cart and over-writing the old one.

Also

I imagine that this could cause you problems down the road:

$woocommerce->cart->add_to_cart( $product_ID, $quantity=1 );

This is the same as putting

$woocommerce->cart->add_to_cart( $product_ID, TRUE );

The reason being is that you are passing to the method the result of $quantity=1 which is almost always going to be a success.

What you mean is:

$woocommerce->cart->add_to_cart( $product_ID, 1 );

However my guess is that you took the method signature which shows that the second parameter is optional and defaults to a value of integer one if left out in which case you could make it even simpler with:

$woocommerce->cart->add_to_cart( $product_ID );

If you only want to pass variables then you need something like this

$quantity = 1;
// ... any other code
$woocommerce->cart->add_to_cart( $product_ID, $quantity );

Answer 4

have you checked the values your passing to $woocommerce->cart->add_to_cart( $product_ID, $quantity=1 )

What about dumping the SQL it generates and attempt to run it, see if it returns any errors?