code: public function execute()
      {
          // Flush all Magento caches
          $types = $this->cacheManager->getAvailableTypes();
          $types = array_diff($types, ['full_page']); // FPC is Handled separately
  
          $this->cacheManager->clean($types);
  
          // Purge everything from Fastly
          $result = $this->api->cleanAll();
  
          if ($result === true) {
              $this->messageManager->addSuccessMessage(
                  __('Full Magento & Fastly Cache has been cleaned.')
              );
          } else {
              $this->getMessageManager()->addErrorMessage(
                  __('Full Magento & Fastly Cache was not cleaned successfully.')
              );
          }
  
          return $this->_redirect('*/cache/index');
      }
docs: Performs cache cleanup and purge all on Fastly service.
  Should be used when "Preserve static assets on purge" is enabled.
  
  @return \Magento\Framework\App\ResponseInterface|\Magento\Framework\Controller\ResultInterface
  @throws \Zend_Uri_Exception