php - What is the best practise for loading extra JavaScript in the footer? -

every page of website consist of:

• generic header
• the page itself
• generic footer

in code page looks this:

<?php require_once('header.php'); load_header('title', 'meta description'); // loads menu ?>  // unique content of page  <?php // footer settings $load_contact_info = true;  // load footer require_once('footer.php'); load_footer($load_contact_info); ?> 

on same pages load content (like more js libraries) in footer.php (right before - closing body tag):

<?php function load_footer($load_contact_info = false) { ?>   <footer>     <?php if ($load_contact_info) { ?>     <div id="contact-us">       // contact info     </div>     <?php } ?>      <div id="inner-footer">       // more generic footer content     </div>    </footer>   <script src="<?php echo($url); ?>js/vendor/jquery.js"></script>      // want load more unique js content here @ pages    </body>   </html> <?php } ?> 

what best practise loading libraries in footer? should extend footer.php more if-yes-load-more this:

if ($google_maps_api) {   // map settings   echo "<script src=\"https://maps.googleapis.com/maps/api/js?callback=initmap\" async defer></script>"; } if ($other_api) {   echo "<script src=\"https://example.com/other-api/\" async defer></script>"; } 

or there other possibilites better?

load libraries should not task footer. footer displays footer. should create new php file , name "handle_js.php"

function print_script_tag($src, $options) {     echo "<script src=\"" . $src . "\" " . $options . "></script>\n"; }  function print_all_script_tags_for_url($url) {   if($url === 'example') {     print_script_tag('library.js','async');   } } 

and in footer file

</footer> print_scripts($url); </body> 

i didn't test code.