Widget:Meta

<script>

   updateMetaTags({
       title: ,
       description: ,
       canonical: ,
       focus_keyword: ,
       keywords: 
   });

function updateMetaTags({ title, description, canonical, focus_keyword, keywords }) {
 
 if (title) {
   document.title = title;
 }

 if (description) {
   let metaDesc = document.querySelector('meta[name="description"]');
   if (!metaDesc) {
     metaDesc = document.createElement('meta');
     metaDesc.setAttribute('name', 'description');
     document.head.appendChild(metaDesc);
   }
   metaDesc.setAttribute('content', description);
 }

 if (canonical) {
   let linkCanonical = document.querySelector('link[rel="canonical"]');
   if (!linkCanonical) {
     linkCanonical = document.createElement('link');
     linkCanonical.setAttribute('rel', 'canonical');
     document.head.appendChild(linkCanonical);
   }
   linkCanonical.setAttribute('href', canonical);
 }

 if (focus_keyword) {
   var focusKeyword = focus_keyword;
   let metaFocus = document.querySelector('meta[name="focus_keyword"]');
   if (!metaFocus) {
     metaFocus = document.createElement('meta');
     metaFocus.setAttribute('name', 'focus_keyword');
     document.head.appendChild(metaFocus);
   }
   metaDesc.setAttribute('content', focusKeyword);
 }

 if (keywords) {
   var keywordList = keywords;
   let metaKeys = document.querySelector('meta[name="keywords"]');
   if (!metaKeys) {
     metaKeys = document.createElement('meta');
     metaKeys.setAttribute('name', 'keywords');
     document.head.appendChild(metaKeys);
   }
   metaDesc.setAttribute('content', keywordList);
 }
}
</script>