Merge pull request #96 from curbengh/autodiscovery

curbengh · web-flow · commit a0cca0b2e443 · 2019-09-26T21:01:15.000+09:30
feat: add rss autodiscovery
diff --git a/README.md b/README.md
@@ -34,6 +34,7 @@ feed:
   content_limit_delim: ' '
   order_by: -date
   icon: icon.png
+  autodiscovery: true
 ```
 
 - **type** - Feed type. (atom/rss2)
@@ -45,3 +46,5 @@ feed:
 - **content_limit_delim** - (optional) If **content_limit** is used to shorten post contents, only cut at the last occurrence of this delimiter before reaching the character limit. Not used by default.
 - **order_by** - Feed order-by. (Default: -date)
 - **icon** - (optional) Custom feed icon. Defaults to a gravatar of email specified in the main config.
+- **autodiscovery** - Add feed [autodiscovery](http://www.rssboard.org/rss-autodiscovery). (Default: `true`)
+  * Many themes already offer this feature, so you may also need to adjust the theme's config if you wish to disable it.
diff --git a/index.js b/index.js
@@ -10,7 +10,8 @@ const config = hexo.config.feed = Object.assign({
   content: true,
   content_limit: 140,
   content_limit_delim: '',
-  order_by: '-date'
+  order_by: '-date',
+  autodiscovery: true
 }, hexo.config.feed);
 
 const type = config.type.toLowerCase();
@@ -33,3 +34,7 @@ if (!extname(config.path)) {
 }
 
 hexo.extend.generator.register('feed', require('./lib/generator'));
+
+if (config.autodiscovery === true) {
+  hexo.extend.filter.register('after_render:html', require('./lib/autodiscovery'));
+}
diff --git a/lib/autodiscovery.js b/lib/autodiscovery.js
@@ -0,0 +1,18 @@
+'use strict';
+
+const { url_for } = require('hexo-util');
+
+function autodiscoveryInject(data) {
+  const { config } = this;
+  const { feed } = config;
+  const type = feed.type.replace(/2$/, '');
+
+  if (!feed.autodiscovery
+    || data.match(/type=['|"]?application\/(atom|rss)\+xml['|"]?/i)) return;
+
+  const autodiscoveryTag = `<link rel="alternate" href="${url_for.call(this, feed.path)}" title="${config.title}" type="application/${type}+xml">`;
+
+  return data.replace(/<head>(?!<\/head>).+?<\/head>/, (str) => str.replace('</head>', `${autodiscoveryTag}</head>`));
+}
+
+module.exports = autodiscoveryInject;
diff --git a/test/index.js b/test/index.js
@@ -235,3 +235,103 @@ describe('Feed generator', () => {
     checkURL('http://localhost/', '/', 'item:nth-of-type(3)>enclosure');
   });
 });
+
+describe('Autodiscovery', () => {
+  const hexo = new Hexo();
+  const autoDiscovery = require('../lib/autodiscovery').bind(hexo);
+  hexo.config.title = 'foo';
+  hexo.config.feed = {
+    type: 'atom',
+    path: 'atom.xml',
+    autodiscovery: true
+  };
+
+  it('default', () => {
+    const content = '<head><link></head>';
+    const result = autoDiscovery(content);
+
+    const $ = cheerio.load(result);
+    $('link[type="application/atom+xml"]').length.should.eql(1);
+    $('link[type="application/atom+xml"]').attr('href').should.eql('/' + hexo.config.feed.path);
+    $('link[type="application/atom+xml"]').attr('title').should.eql(hexo.config.title);
+
+    result.should.eql('<head><link><link rel="alternate" href="/atom.xml" title="foo" type="application/atom+xml"></head>');
+  });
+
+  it('prepend root', () => {
+    hexo.config.root = '/root/';
+    const content = '<head><link></head>';
+    const result = autoDiscovery(content);
+
+    const $ = cheerio.load(result);
+    $('link[type="application/atom+xml"]').attr('href').should.eql(hexo.config.root + hexo.config.feed.path);
+
+    result.should.eql('<head><link><link rel="alternate" href="/root/atom.xml" title="foo" type="application/atom+xml"></head>');
+    hexo.config.root = '/';
+  });
+
+  it('disable autodiscovery', () => {
+    hexo.config.feed.autodiscovery = false;
+    const content = '<head><link></head>';
+    const result = autoDiscovery(content);
+
+    const resultType = typeof result;
+    resultType.should.eql('undefined');
+    hexo.config.feed.autodiscovery = true;
+  });
+
+  it('no duplicate tag', () => {
+    const content = '<head><link>'
+      + '<link rel="alternate" href="/atom.xml" title="foo" type="application/atom+xml"></head>';
+    const result = autoDiscovery(content);
+
+    const resultType = typeof result;
+    resultType.should.eql('undefined');
+  });
+
+  it('ignore empty head tag', () => {
+    const content = '<head></head>'
+      + '<head><link></head>'
+      + '<head></head>';
+    const result = autoDiscovery(content);
+
+    const $ = cheerio.load(result);
+    $('link[type="application/atom+xml"]').length.should.eql(1);
+
+    const expected = '<head></head>'
+    + '<head><link><link rel="alternate" href="/atom.xml" title="foo" type="application/atom+xml"></head>'
+    + '<head></head>';
+    result.should.eql(expected);
+  });
+
+  it('apply to first non-empty head tag only', () => {
+    const content = '<head></head>'
+      + '<head><link></head>'
+      + '<head><link></head>';
+    const result = autoDiscovery(content);
+
+    const $ = cheerio.load(result);
+    $('link[type="application/atom+xml"]').length.should.eql(1);
+
+    const expected = '<head></head>'
+    + '<head><link><link rel="alternate" href="/atom.xml" title="foo" type="application/atom+xml"></head>'
+    + '<head><link></head>';
+    result.should.eql(expected);
+  });
+
+  it('rss2', () => {
+    hexo.config.feed = {
+      type: 'rss2',
+      path: 'rss2.xml',
+      autodiscovery: true
+    };
+    const content = '<head><link></head>';
+    const result = autoDiscovery(content);
+
+    const $ = cheerio.load(result);
+    $('link[rel="alternate"]').attr('type').should.eql('application/rss+xml');
+
+    result.should.eql('<head><link><link rel="alternate" href="/rss2.xml" title="foo" type="application/rss+xml"></head>');
+  });
+
+});
