fix: external_link should use after_render

lib/hexo/default_config.js

@@ -29,7 +29,11 @@ module.exports = {
   new_post_name: ':title.md',
   default_layout: 'post',
   titlecase: false,
-  external_link: true,
+  external_link: {
+    enable: true,
+    field: 'site',
+    exclude: ''
+  },
   filename_case: 0,
   render_drafts: false,
   post_asset_folder: false,

lib/plugins/filter/after_post_render/external_link.js

@@ -1,20 +1,43 @@
 'use strict';
 
-const url = require('url');
+const { parse } = require('url');
+
+const isExternal = (url, config) => {
+  const exclude = Array.isArray(config.external_link.exclude) ? config.external_link.exclude :
+    [config.external_link.exclude];
+  const data = parse(url);
+  const host = data.hostname;
+  const sitehost = parse(config.url).hostname || config.url;
+
+  if (!data.protocol || !sitehost) return false;
+
+  if (exclude && exclude.length) {
+    for (const i of exclude) {
+      if (host === i) return false;
+    }
+  }
+
+  if (host !== sitehost) return true;
+
+  return false;
+};
 
 function externalLinkFilter(data) {
   const { config } = this;
-  if (!config.external_link) return;
 
-  const siteHost = url.parse(config.url).hostname || config.url;
+  if (typeof config.external_link === 'undefined' || typeof config.external_link === 'object' ||
+    config.external_link === true) {
+    config.external_link = Object.assign({
+      enable: true,
+      field: 'site',
+      exclude: ''
+    }, config.external_link);
+  }
+  if (config.external_link === false || config.external_link.enable === false ||
+    config.external_link.field !== 'post') return;
 
   data.content = data.content.replace(/<a.*?(href=['"](.*?)['"]).*?>/gi, (str, hrefStr, href) => {
-    if (/target=/gi.test(str)) return str;
-
-    const data = url.parse(href);
-    // Exit if the link doesn't have protocol, which means it's a internal link
-    // Exit if the url has same host with config.url
-    if (!data.protocol || data.hostname === siteHost) return str;
+    if (/target=/gi.test(str) || !isExternal(href, config)) return str;
 
     if (/rel=/gi.test(str)) {
       str = str.replace(/rel="(.*?)"/gi, (relStr, rel) => {
@@ -26,7 +49,6 @@ function externalLinkFilter(data) {
 
     return str.replace(hrefStr, `${hrefStr} target="_blank" rel="noopener"`);
   });
-
 }
 
 module.exports = externalLinkFilter;

lib/plugins/filter/after_render/external_link.js

@@ -0,0 +1,62 @@
+'use strict';
+
+const { parse } = require('url');
+
+/**
+ * Check whether the link is external
+ * @param {String} url The url to check
+ * @param {Object} config The site config
+ * @returns {Boolean} True if the link doesn't have protocol or link has same host with config.url
+ */
+const isExternal = (url, config) => {
+  const exclude = Array.isArray(config.external_link.exclude) ? config.external_link.exclude :
+    [config.external_link.exclude];
+  const data = parse(url);
+  const host = data.hostname;
+  const sitehost = parse(config.url).hostname || config.url;
+
+  if (!data.protocol || !sitehost) return false;
+
+  if (exclude && exclude.length) {
+    for (const i of exclude) {
+      if (host === i) return false;
+    }
+  }
+
+  if (host !== sitehost) return true;
+
+  return false;
+};
+
+function externalLinkFilter(data) {
+  const { config } = this;
+
+  if (typeof config.external_link === 'undefined' || typeof config.external_link === 'object' ||
+    config.external_link === true) {
+    config.external_link = Object.assign({
+      enable: true,
+      field: 'site',
+      exclude: ''
+    }, config.external_link);
+  }
+  if (config.external_link === false || config.external_link.enable === false ||
+    config.external_link.field !== 'site') return;
+
+  data = data.replace(/<a.*?(href=['"](.*?)['"]).*?>/gi, (str, hrefStr, href) => {
+    if (/target=/gi.test(str) || !isExternal(href, config)) return str;
+
+    if (/rel=/gi.test(str)) {
+      str = str.replace(/rel="(.*?)"/gi, (relStr, rel) => {
+        if (!rel.includes('noopenner')) relStr = relStr.replace(rel, `${rel} noopener`);
+        return relStr;
+      });
+      return str.replace(hrefStr, `${hrefStr} target="_blank"`);
+    }
+
+    return str.replace(hrefStr, `${hrefStr} target="_blank" rel="noopener"`);
+  });
+
+  return data;
+}
+
+module.exports = externalLinkFilter;

lib/plugins/filter/after_render/index.js

@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = ctx => {
+  const { filter } = ctx.extend;
+
+  filter.register('after_render:html', require('./external_link'));
+  filter.register('after_render:html', require('./meta_generator'));
+};

lib/plugins/filter/index.js

@@ -3,6 +3,7 @@
 module.exports = ctx => {
   const { filter } = ctx.extend;
 
+  require('./after_render')(ctx);
   require('./after_post_render')(ctx);
   require('./before_post_render')(ctx);
   require('./before_exit')(ctx);
@@ -11,5 +12,4 @@ module.exports = ctx => {
 
   filter.register('new_post_path', require('./new_post_path'));
   filter.register('post_permalink', require('./post_permalink'));
-  filter.register('after_render:html', require('./meta_generator'));
 };