Dialogflow CX Messenger

<meta name="viewport" content="width=device-width, initial-scale=1">

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate" />
  <meta http-equiv="Pragma" content="no-cache" />
  <meta http-equiv="Expires" content="0" />
  <title>My chat</title>
  <style>
    df-messenger {
      /*
       * Customize as required. df-messenger will fill the
       * space that is provided.
      */
      position: absolute;
      right: 0;
      top: 0;
      bottom: 0;
      width: 320px;
    }
  </style>
  <script src="https://www.gstatic.com/dialogflow-console/fast/df-messenger/prod/v1/df-messenger.js"></script>
</head>
<body>
<df-messenger
    location="global" <!-- TODO: update agent location as needed -->
    project-id="my-project-id" <!-- TODO: update project ID -->
    agent-id="my-agent-id" <!-- TODO: update agent ID -->
    language-code="en" <!-- TODO: update agent language as needed -->
>
  <df-messenger-chat
      chat-title="Agent Name" <!-- TODO: update dialog title as needed -->
  ></df-messenger-chat>
</df-messenger>

<script>
  // An example of handling events: Navigate to the first suggested URL.
  document.addEventListener('df-url-suggested', (event) => {
    if (Array.isArray(event.detail.suggestedUrls) &&
      event.detail.suggestedUrls.length) {
      window.location.href = event.detail.suggestedUrls[0];
  }
});
</script>
</body>
</html>

class CustomFeedbackElement extends HTMLElement {
  constructor() {
    super();
    // It is not strictly required but recommended to contain the custom
    // element in a shadow root.
    this.renderRoot = this.attachShadow({mode: 'open'});
  }

  // Web component Lifecycle method.
  connectedCallback() {
    const wrapper = document.createElement('div');

    // Build the component as required.
    const button = document.createElement('button');
    button.innerText = 'Submit';
    button.addEventListener('click', () => {
      this._onSubmitClick();
    });
    wrapper.appendChild(button);

    this.renderRoot.appendChild(wrapper);
  }

  // Called when Submit button is clicked.
  _onSubmitClick() {
    const event = new CustomEvent("df-custom-submit-feedback-clicked", {
      // `detail` may be any string,
      // this will be sent to the backend to be stored.
      detail: JSON.stringify({
        "usefulness": 2,
        "accuracy": 3,
      }),
      // Required to propagate up the DOM tree
      // https://developer.mozilla.org/en-US/docs/Web/API/Event/bubbles
      bubbles: true,
      // Required to propagate across ShadowDOM
      // https://developer.mozilla.org/en-US/docs/Web/API/Event/composed
      composed: true,
   });
   this.dispatchEvent(event);
  }
}

(function() {
  // Registers the element. This name must be "df-external-custom-feedback".
  customElements.define('df-external-custom-feedback', CustomFeedbackElement);
})();