Create programmatically a WooCommerce product variation with new attribute values

Update January 2020: Changed to WC_Product method get_name() instead of get_title()
Update September 2018: Handling taxonomy creation (Thanks to Carl F. Corneil)

From a defined variable product ID You will find below, a custom function that will add (create) a Product variation. The variable parent product needs to have set for it the needed attributes.

You will need to provide some information as:

• the array of attributes/values
• the Sku, prices and stock….

This data has to be stored in a formatted multi dimensional array (see an example at the end).

This function will check if the attributes values (term name) already exist and if not:

• it create it for the product attribute
• set it in the parent variable product.

The custom function code:

/** * Create a product variation for a defined variable product ID. * * @since 3.0.0 * @param int   $product_id | Post ID of the product parent variable product. * @param array $variation_data | The data to insert in the product. */function create_product_variation( $product_id, $variation_data ){    // Get the Variable product object (parent)    $product = wc_get_product($product_id);    $variation_post = array(        'post_title'  => $product->get_name(),        'post_name'   => 'product-'.$product_id.'-variation',        'post_status' => 'publish',        'post_parent' => $product_id,        'post_type'   => 'product_variation',        'guid'        => $product->get_permalink()    );    // Creating the product variation    $variation_id = wp_insert_post( $variation_post );    // Get an instance of the WC_Product_Variation object    $variation = new WC_Product_Variation( $variation_id );    // Iterating through the variations attributes    foreach ($variation_data['attributes'] as $attribute => $term_name )    {        $taxonomy = 'pa_'.$attribute; // The attribute taxonomy        // If taxonomy doesn't exists we create it (Thanks to Carl F. Corneil)        if( ! taxonomy_exists( $taxonomy ) ){            register_taxonomy(                $taxonomy,               'product_variation',                array(                    'hierarchical' => false,                    'label' => ucfirst( $attribute ),                    'query_var' => true,                    'rewrite' => array( 'slug' => sanitize_title($attribute) ), // The base slug                ),            );        }        // Check if the Term name exist and if not we create it.        if( ! term_exists( $term_name, $taxonomy ) )            wp_insert_term( $term_name, $taxonomy ); // Create the term        $term_slug = get_term_by('name', $term_name, $taxonomy )->slug; // Get the term slug        // Get the post Terms names from the parent variable product.        $post_term_names =  wp_get_post_terms( $product_id, $taxonomy, array('fields' => 'names') );        // Check if the post term exist and if not we set it in the parent variable product.        if( ! in_array( $term_name, $post_term_names ) )            wp_set_post_terms( $product_id, $term_name, $taxonomy, true );        // Set/save the attribute data in the product variation        update_post_meta( $variation_id, 'attribute_'.$taxonomy, $term_slug );    }    ## Set/save all other data    // SKU    if( ! empty( $variation_data['sku'] ) )        $variation->set_sku( $variation_data['sku'] );    // Prices    if( empty( $variation_data['sale_price'] ) ){        $variation->set_price( $variation_data['regular_price'] );    } else {        $variation->set_price( $variation_data['sale_price'] );        $variation->set_sale_price( $variation_data['sale_price'] );    }    $variation->set_regular_price( $variation_data['regular_price'] );    // Stock    if( ! empty($variation_data['stock_qty']) ){        $variation->set_stock_quantity( $variation_data['stock_qty'] );        $variation->set_manage_stock(true);        $variation->set_stock_status('');    } else {        $variation->set_manage_stock(false);    }        $variation->set_weight(''); // weight (reseting)    $variation->save(); // Save the data}

Code goes in function.php file of your active child theme (or theme) or also in any plugin file.

Usage (example with 2 attributes):

$parent_id = 746; // Or get the variable product id dynamically// The variation data$variation_data =  array(    'attributes' => array(        'size'  => 'M',        'color' => 'Green',    ),    'sku'           => '',    'regular_price' => '22.00',    'sale_price'    => '',    'stock_qty'     => 10,);// The function to be runcreate_product_variation( $parent_id, $variation_data );

Tested and works.

Part 2: Create programmatically a variable product and two new attributes in WooCommerce

You will get this in backend:

And it will work perfectly in front end.

Related: Create programmatically a product using CRUD methods in Woocommerce 3

I'm just going to throw this out there, since i couldn't get any of the above examples working. Don't ask me why as other people seem to have success. So, i took the minimalist approach and tried to figure out the bare essentials for a product attribute + variation (by creating it manually in wp and looking at the db) and came up with this.

$article_name = 'Test';$post_id = wp_insert_post( array(    'post_author' => 1,    'post_title' => $article_name,    'post_content' => 'Lorem ipsum',    'post_status' => 'publish',    'post_type' => "product",) );wp_set_object_terms( $post_id, 'variable', 'product_type' );$attr_label = 'Test attribute';$attr_slug = sanitize_title($attr_label);$attributes_array[$attr_slug] = array(    'name' => $attr_label,    'value' => 'alternative 1 | alternative 2',    'is_visible' => '1',    'is_variation' => '1',    'is_taxonomy' => '0' // for some reason, this is really important       );update_post_meta( $post_id, '_product_attributes', $attributes_array );$parent_id = $post_id;$variation = array(    'post_title'   => $article_name . ' (variation)',    'post_content' => '',    'post_status'  => 'publish',    'post_parent'  => $parent_id,    'post_type'    => 'product_variation');$variation_id = wp_insert_post( $variation );update_post_meta( $variation_id, '_regular_price', 2 );update_post_meta( $variation_id, '_price', 2 );update_post_meta( $variation_id, '_stock_qty', 10 );update_post_meta( $variation_id, 'attribute_' . $attr_slug, 'alternative 1' );WC_Product_Variable::sync( $parent_id );$variation_id = wp_insert_post( $variation );update_post_meta( $variation_id, '_regular_price', 2 );update_post_meta( $variation_id, '_price', 2 );update_post_meta( $variation_id, '_stock_qty', 10 );update_post_meta( $variation_id, 'attribute_' . $attr_slug, 'alternative 2' );WC_Product_Variable::sync( $parent_id );

This is not using global product attributes, but article specific ones. Hope it helps someone as i was about ready to tear my hair out before i got it working.

Not sure why, but none of these solutions worked for me, so I decided to create my own:

<?php/** * Create a variable product on woocommerce * @return int Product ID */function pricode_create_product(){    $product = new WC_Product_Variable();    $product->set_description('T-shirt variable description');    $product->set_name('T-shirt variable');    $product->set_sku('test-shirt');    $product->set_price(1);    $product->set_regular_price(1);    $product->set_stock_status();    return $product->save();}/** * Create Product Attributes  * @param  string $name    Attribute name * @param  array $options Options values * @return Object          WC_Product_Attribute  */function pricode_create_attributes( $name, $options ){    $attribute = new WC_Product_Attribute();    $attribute->set_id(0);    $attribute->set_name($name);    $attribute->set_options($options);    $attribute->set_visible(true);    $attribute->set_variation(true);    return $attribute;}/** * [pricode_create_variations description] * @param  [type] $product_id [description] * @param  [type] $values     [description] * @return [type]             [description] */function pricode_create_variations( $product_id, $values ){    $variation = new WC_Product_Variation();    $variation->set_parent_id( $product_id );    $variation->set_attributes($values);    $variation->set_status('publish');    $variation->set_sku($data->sku);    $variation->set_price($data->price);    $variation->set_regular_price($data->price);    $variation->set_stock_status();    $variation->save();    $product = wc_get_product($product_id);    $product->save();}//Adding product$product = pricode_create_product();//Creating Attributes $atts = [];$atts[] = pricode_create_attributes('color',['red', 'green']);$atts[] = pricode_create_attributes('size',['S', 'M']);//Adding attributes to the created product$product->set_attributes( $atts );$product->save();//Create variationspricode_create_variations( $product->get_id(), ['color' => 'red', 'size' => 'M']);

Hope it can help others.