Drupal remove white-space from HTML

Add this simple function into your theme’s template.php in order to strip out unnecessary whitespace and line breaks, saving a bit of file size where possible (I saved 17kb from my homepage). If a page contains a <pre> or <textarea> tag, it is left alone, as to not affect code blocks or text typed in a form.

// Minify HTML output.
function sonspring_process_html(&$vars) {
  $before = array(
    "/>\s\s+/",
    "/\s\s+</",
    "/>\t+</",
    "/\s\s+(?=\w)/",
    "/(?<=\w)\s\s+/"
  );

  $after = array('> ', ' <', '> <', ' ', ' ');

  // Page top.
  $page_top = $vars['page_top'];
  $page_top = preg_replace($before, $after, $page_top);
  $vars['page_top'] = $page_top;

  // Page content.
  if (!preg_match('/<pre|<textarea/', $vars['page'])) {
    $page = $vars['page'];
    $page = preg_replace($before, $after, $page);
    $vars['page'] = $page;
  }

  // Page bottom.
  $page_bottom = $vars['page_bottom'];
  $page_bottom = preg_replace($before, $after, $page_bottom);
  $vars['page_bottom'] = $page_bottom . drupal_get_js('footer');
}