index.js

/* eslint-env browser */
const LoadScript = {
  install: function (Vue) {
    Vue.loadScript = Vue.prototype.$loadScript = function (src) { // eslint-disable-line no-param-reassign
      return new Promise(function (resolve, reject) {
        let shouldAppend = false;
        let el = document.querySelector('script[src="' + src + '"]');
        if (!el) {
          el = document.createElement('script');
          el.type = 'text/javascript';
          el.async = true;
          el.src = src;
          shouldAppend = true;
        }
        else if (el.hasAttribute('data-loaded')) {
          resolve(el);
          return;
        }

        el.addEventListener('error', reject);
        el.addEventListener('abort', reject);
        el.addEventListener('load', function loadScriptHandler() {
          el.setAttribute('data-loaded', true);
          resolve(el);
        });

        if (shouldAppend) document.head.appendChild(el);
      });
    };

    Vue.unloadScript = Vue.prototype.$unloadScript = function (src) { // eslint-disable-line no-param-reassign
      return new Promise(function (resolve, reject) {
        const el = document.querySelector('script[src="' + src + '"]');

        if (!el) {
          reject();
          return;
        }

        document.head.removeChild(el);

        resolve();
      });
    };
  },
};

export default LoadScript;