commercetools-8.x-1.2-alpha1/modules/commercetools_decoupled/components/blocks/cart-block/js/CartBlock.js

class CartBlock extends HTMLElement {
  connectedCallback() {
    const cartSummary = document.createElement('ct-cart-summary');
    cartSummary.componentConfig = window.commercetools.getComponentConfig(this);
    this.appendChild(cartSummary);
  }
}

customElements.define('ct-cart-block', CartBlock);