add: github搜索结果 (#1325)

closes #1289

docs/README.md

@@ -668,6 +668,15 @@ GitHub 官方也提供了一些 RSS:
 
 <route name="仓库 Stars" author="HenryQW" example="/github/stars/DIYgod/RSSHub" path="/github/stars/:user/:repo" :paramsDesc="['用户名', '仓库名']"/>
 
+<route name="搜索结果" author="LogicJake" example="/github/search/RSSHub/bestmatch/desc" path="/github/search/:query/:sort?/:order?" :paramsDesc="['搜索关键词', '排序选项（默认为bestmatch）','排序顺序，desc和asc（默认desc降序）']"/>
+
+| 排序选项           | sort      |
+| ------------------ | --------- |
+| 最佳匹配           | bestmatch |
+| 根据 star 数量排序 | stars     |
+| 根据 fork 数量排序 | forks     |
+| 根据更新时间排序   | updated   |
+
 ### 开源中国
 
 <route name="资讯" author="tgly307" example="/oschina/news" path="/oschina/news"/>

lib/router.js

@@ -312,6 +312,7 @@ router.get('/github/trending/:since/:language?', require('./routes/github/trendi
 router.get('/github/issue/:user/:repo', require('./routes/github/issue'));
 router.get('/github/user/followers/:user', require('./routes/github/follower'));
 router.get('/github/stars/:user/:repo', require('./routes/github/star'));
+router.get('/github/search/:query/:sort?/:order?', require('./routes/github/search'));
 
 // f-droid
 router.get('/fdroid/apprelease/:app', require('./routes/fdroid/apprelease'));

lib/routes/github/search.js

@@ -0,0 +1,47 @@
+const axios = require('../../utils/axios');
+const cheerio = require('cheerio');
+const url = require('url');
+
+const host = 'https://github.com';
+
+module.exports = async (ctx) => {
+    const query = ctx.params.query;
+    let sort = ctx.params.sort || 'bestmatch';
+    const order = ctx.params.order || 'desc';
+
+    if (sort === 'bestmatch') {
+        sort = '';
+    }
+
+    const suffix = 'search?o='.concat(order, '&q=', query, '&s=', sort, '&type=Repositories');
+    const link = url.resolve(host, suffix);
+    const response = await axios.get(link);
+    const $ = cheerio.load(response.data);
+
+    const out = $('.repo-list li')
+        .slice(0, 10)
+        .map(function() {
+            const single = {
+                title: $(this)
+                    .find('div h3 a')
+                    .text(),
+                link: host.concat(
+                    $(this)
+                        .find('div h3 a')
+                        .attr('href')
+                ),
+                description: $(this)
+                    .find('div p')
+                    .text()
+                    .trim(),
+            };
+            return single;
+        })
+        .get();
+
+    ctx.state.data = {
+        title: `${query}的搜索结果`,
+        link: link,
+        item: out,
+    };
+};