Redirecting user to a dynamic download page after form submission

How To
5

I don’t know where you got this filter-name from, but this doesn’t exist.
To create a dynamic-data-tag, you need to first register it:

add_filter('bricks/dynamic_tags_list', function ($tags) {
  $tags[] = [
    'name'  => '{custom_prdouct_pdf}',
    'label' => 'Custom Product PDF',
    'group' => 'My Dynamic Data Group', // Change to your Liking
  ];
  return $tags;
});

After that we have to write some logic. In your case we need to use these two filters:

add_filter('bricks/dynamic_data/render_content', 'prexix_render_custom_product_pdf', 20, 3);
add_filter('bricks/frontend/render_data', 'prexix_render_custom_product_pdf', 20, 2);
function prexix_render_custom_product_pdf($content, $post, $context = 'text')
{

  if (strpos($content, '{custom_product_pdf}') === false) return $content;

  $value = '';

  if (isset($_GET['download - pdf'])) {
    $product_id = intval($_GET['download - pdf']);

    $pdf_url = get_field('product_pdf', $product_id);

    if ($pdf_url && filter_var($pdf_url, FILTER_VALIDATE_URL)) {
      $value = $pdf_url;
    }
  }

  $content = str_replace('{custom_product_pdf}', $value, $content);

  return $content;
}

This code was not tested, but should work from what I imagine.

And remember to use dynamic data with only one bracket on each side {custom_product_pdf}.

Cheers Suat