Similar Article code

PLOSSimilarArticles.js

let containerClass = 'related-articles-container';
let listId = 'related-articles-list';
let header = 'Similar PLOS Articles';
let params = new URLSearchParams(window.location.search);
let relatedDoi = params.get('id');
let allowedTypes = ['Research Article', 'Front Matter'];
// GTM doesn't support backtick notation, refactor
function relatedCallback (data) {
  console.log(data)
  let relatedDocs = data['moreLikeThis'][relatedDoi]['docs']
  let listItems = relatedDocs.reduce(function(list, doc) {
    let listItem = `<li><a href="https://dx.plos.org/${doc.id}">${doc.title}</a></li>`;
    return allowedTypes.indexOf(doc.article_type) != -1 ? list + listItem : list;
  }, '')
  if (listItems == '') { return null; } // do nothing if no thingies
  $(`<div class="${containerClass}"><h3>${header}</h3><ul id="${listId}">${listItems}</ul></div>`).insertAfter('a[data-target="crossmark"]')
}

if ($(`.${containerClass}`).length == 0) {
  $.ajax({
      url: `https://api.plos.org/search?wt=json&json.wrf=relatedCallback&fl=id,title,article_type&mlt.fl=abstract&mlt=true&q=id:${relatedDoi}` ,
      type: 'GET',
      dataType: 'jsonp'
  });
}