fix(perf): process external links in frontend

layout/common/scripts.ejs

@@ -2,8 +2,23 @@
 <%- _js(cdn('moment', '2.22.2', 'min/moment-with-locales.min.js')) %>
 <script>moment.locale("<%= get_config('language', 'en') %>");</script>
 
+<%
+let externalLink = get_config('external_link');
+if (typeof externalLink === 'boolean') {
+    externalLink = { enable: externalLink, exclude: [] };
+} else {
+    externalLink = {
+        enable: typeof externalLink.enable === 'boolean' ? externalLink.enable : true,
+        exclude: externalLink.exclude || []
+    };
+}
+%>
 <script>
 var IcarusThemeSettings = {
+    site: {
+        url: '<%= config.url %>',
+        external_link: <%- JSON.stringify(externalLink) %>
+    },
     article: {
         highlight: {
             clipboard: <%= get_config('article.highlight.clipboard', true) %>,
@@ -14,13 +29,13 @@ var IcarusThemeSettings = {
 </script>
 
 <% if (get_config('article.highlight.clipboard')) { %>
-    <%- _js(cdn('clipboard', '2.0.4', 'dist/clipboard.min.js'), true) %>
+<%- _js(cdn('clipboard', '2.0.4', 'dist/clipboard.min.js'), true) %>
 <% } %>
 
 <% if (has_config('plugins')) { %>
-    <% for (let plugin in get_config('plugins')) { %>
-    <%- _partial('plugin/' + plugin, { head: false, plugin: get_config('plugins')[plugin] }) %>
-    <% } %>
+<% for (let plugin in get_config('plugins')) { %>
+<%- _partial('plugin/' + plugin, { head: false, plugin: get_config('plugins')[plugin] }) %>
+<% } %>
 <% } %>
 
 <%- _js('js/main', true) %>

package.json

@@ -1,5 +1,8 @@
 {
   "name": "hexo-theme-icarus",
   "version": "2.6.0",
-  "private": true
-}
+  "private": true,
+  "engines": {
+    "node": ">=8.3.0"
+  }
+}

source/js/main.js

@@ -103,4 +103,49 @@
         $mask.on('click', toggleToc);
         $('.navbar-main .catalogue').on('click', toggleToc);
     }
+
+    // hexo-util/lib/is_external_link.js
+    function isExternalLink(input, sitehost, exclude) {
+        try {
+            sitehost = new URL(sitehost).hostname;
+        } catch (e) { }
+
+        if (!sitehost) return false;
+
+        // handle relative url
+        const data = new URL(input, 'http://' + sitehost);
+
+        // handle mailto: javascript: vbscript: and so on
+        if (data.origin === 'null') return false;
+
+        const host = data.hostname;
+
+        if (exclude) {
+            exclude = Array.isArray(exclude) ? exclude : [exclude];
+
+            if (exclude && exclude.length) {
+                for (const i of exclude) {
+                    if (host === i) return false;
+                }
+            }
+        }
+
+        if (host !== sitehost) return true;
+
+        return false;
+    }
+
+    if (typeof (IcarusThemeSettings) !== 'undefined' &&
+        typeof (IcarusThemeSettings.site.url) !== 'undefined' &&
+        typeof (IcarusThemeSettings.site.external_link) !== 'undefined' &&
+        IcarusThemeSettings.site.external_link.enable) {
+        $('.article .content a').filter(function (i, link) {
+            return link.href && link.classList.length === 0 && isExternalLink(link.href,
+                IcarusThemeSettings.site.url,
+                IcarusThemeSettings.site.external_link.exclude);
+        }).each(function (i, link) {
+            link.relList.add('noopener');
+            link.target = '_blank';
+        });
+    }
 })(jQuery);