I have a site which uses Google's API's for jquery and a fallback for jquery. The problem is that I can't get the fallback to happen immediately after the jquery api attempt. What happens is that the fallback file is added after a range of plugin scripts which require jquery and then fails. How can I change the order or location where these plugin scripts are added? Below just gives me the registered files:
var_dump( $GLOBALS['wp_scripts']->registered );
Add your fallback code into a plugin and save your plugin in the MU folder: http://codex.wordpress.org/Must_Use_Plugins.
Then this will run before any other plugins
Here's a slightly different way of doing it, replacing the existing enqueued script with the CDN and adding a fallback. Also matches to your existing jQuery version in WordPress. Found it pretty reliable in practice:
add_action('wp_enqueue_scripts','jquery_cdn_with_fallback');
function jquery_cdn_with_fallback() {
global $wp_version;
// get the jquery handle depending on WP version
$jqueryhandle = (version_compare($wp_version, '3.6-alpha1', '>=') ) ? 'jquery-core' : 'jquery';
// get the version of built-in Jquery in WordPress
$wpjquery = $GLOBALS['wp_scripts']->registered[$jquery_handle]->ver;
$jquery = 'https://ajax.googleapis.com/ajax/libs/jquery/'.$wpjquery.'/jquery.min.js';
// replace the existing jquery script URL
wp_deregister_script($jqueryhandle);
wp_register_script($jqueryhandle, $jquery, false, $jqueryversion, true);
wp_enqueue_script($jqueryhandle);
// add fallback via script_loader_tag filter
add_filter('script_loader_tag','jquery_fallback', 10, 2);
function jquery_fallback($scripttag, $handle) {
global $wp_version;
$jqueryhandle = (version_compare($wp_version, '3.6-alpha1', '>=') ) ? 'jquery-core' : 'jquery';
if ( ($handle == $jqueryhandle) && (strstr($scripttag,'jquery.min.js')) ) {
$jquery = urlencode(site_url().'/wp-includes/js/jquery/jquery.js');
// instant fallback to local WP jquery on failure
$fallback = "</script><script>if (!window.jQuery) {document.write(unescape('%3Cscript src=\"".$jquery."\"%3E%3C\/script%3E'));}</script>";
$scripttag = str_replace('</script>',$fallback, $scripttag);
}
return $scripttag;
}
}
Adapted it for WP based on this answer: https://stackoverflow.com/questions/1014203/best-way-to-use-googles-hosted-jquery-but-fall-back-to-my-hosted-library-on-go
