Class Button

// ...

const action = CardService.newAuthorizationAction().setAuthorizationUrl('url');
CardService.newTextButton().setText('Authorize').setAuthorizationAction(action);

// ...

const action = CardService.newAction().setFunctionName('composeEmailCallback');
CardService.newTextButton()
    .setText('Compose Email')
    .setComposeAction(action, CardService.ComposedEmailType.REPLY_AS_DRAFT);

// ...

function composeEmailCallback(e) {
  const thread = GmailApp.getThreadById(e.threadId);
  const draft = thread.createDraftReply('This is a reply');
  return CardService.newComposeActionResponseBuilder()
      .setGmailDraft(draft)
      .build();
}

// ...

const action = CardService.newAction().setFunctionName('notificationCallback');
CardService.newTextButton()
    .setText('Create notification')
    .setOnClickAction(action);

// ...

function notificationCallback() {
  return CardService.newActionResponseBuilder()
      .setNotification(
          CardService.newNotification().setText('Some info to display to user'),
          )
      .build();
}

// ...

const action = CardService.newAction().setFunctionName('openLinkCallback');
CardService.newTextButton()
    .setText('Open Link')
    .setOnClickOpenLinkAction(action);

// ...

function openLinkCallback() {
  return CardService.newActionResponseBuilder()
      .setOpenLink(CardService.newOpenLink().setUrl('https://www.google.com'))
      .build();
}

const overflowMenuItem =
    CardService.newOverflowMenuItem()
        .setStartIcon(
            CardService.newIconImage().setIconUrl(
                'https://www.google.com/images/branding/googleg/1x/googleg_standard_color_64dp.png',
                ),
            )
        .setText('Open Link')
        .setOpenLink(
            CardService.newOpenLink().setUrl('https://www.google.com'));

const overflowMenu =
    CardService.newOverflowMenu().addMenuItem(overflowMenuItem).build();