feat(test-url): auto detect feed url

Author: fengkx

i18n/en.yaml

@@ -40,3 +40,4 @@ NO: NO
 CANCEL: Canceled
 PAGE_PRE: Previous page
 PAGE_NEXT: Next page
+FOUND_FEED_MORE_THAN_ONE: Found feed more than 1

i18n/zh-cn.yaml

@@ -40,3 +40,4 @@ NO: 否
 CANCEL: 取消操作
 PAGE_PRE: 上一页
 PAGE_NEXT: 下一页
+FOUND_FEED_MORE_THAN_ONE: 找到不止一个订阅地址

middlewares/test-url.js

@@ -1,24 +1,55 @@
 const got = require('../utils/got');
+const feedUtil = require('../utils/feed');
 const Parser = require('rss-parser');
 const RSS = require('../proxies/rssFeed');
+const i18n = require('../i18n');
 
+// eslint-disable-next-line max-lines-per-function
 module.exports = async (ctx, next) => {
     const url = encodeURI(ctx.state.feedUrl);
-    const feed = await RSS.getFeedByUrl(url);
+    let feed = await RSS.getFeedByUrl(url);
     if (feed) {
         ctx.state.feed = feed;
         ctx.state.feed.title = feed.feed_title;
         await next();
     } else {
         try {
             const res = await got.get(url);
-            // handle redirect
-            ctx.state.feedUrl = decodeURI(res.url);
-            const parser = new Parser();
-            let feed = await parser.parseString(res.body);
-            delete feed.items;
-            ctx.state.feed = feed;
+            ctx.state.feedUrl = decodeURI(res.url); // handle redirect
+            feed = await feedUtil.isFeedValid(res.body);
+            if (!feed) {
+                // check feedUrl
+                ctx.state.feedUrl = await feedUtil.findFeed(res.body, res.url);
+                ctx.state.feedUrl = ctx.state.feedUrl.map(decodeURI);
+                const parser = new Parser();
+                switch (ctx.state.feedUrl.length) {
+                    case 0:
+                        throw new Error('FETCH_ERROR');
+                    case 1:
+                        // eslint-disable-next-line no-case-declarations
+                        const res = await got(encodeURI(ctx.state.feedUrl[0]));
+                        feed = await parser.parseString(res.body);
+                        delete feed.items;
+                        ctx.state.feed = feed;
+                        await next(); // next
+                        break;
+                    default:
+                        // eslint-disable-next-line no-case-declarations
+                        const builder = [];
+                        builder.push(
+                            `**${i18n['FOUND_FEED_MORE_THAN_ONE']}:**`
+                        );
+                        builder.push(...ctx.state.feedUrl);
+                        ctx.replyWithMarkdown(builder.join('\n'));
+                        break;
+                }
+            } else {
+                delete feed.items;
+                ctx.state.feed = feed;
+                await next();
+            }
         } catch (e) {
+            if (e instanceof Error) throw e;
             if (e.response) {
                 switch (e.response.status) {
                     case 404:
@@ -31,6 +62,5 @@ module.exports = async (ctx, next) => {
                 throw new Error('FETCH_ERROR');
             }
         }
-        await next();
     }
 };

utils/feed.js

@@ -1,21 +1,32 @@
 const cheerio = require('cheerio');
 const RSSParser = require('rss-parser');
-exports.isFeedValid = async function (feedStr) {
+
+exports.isFeedValid = async function(feedStr) {
     const parser = new RSSParser();
+    let feed;
     try {
-        await parser.parseString(feedStr)
+        feed = await parser.parseString(feedStr);
     } catch (e) {
         return false;
     }
-    return true;
-}
+    return feed;
+};
 
-exports.findFedd = async function (html) {
+exports.findFeed = async function(html, reqUrl) {
+    reqUrl = new URL(reqUrl);
     const $ = cheerio.load(html);
-    return $('[rel=alternate]')
+    const urls = $('head')
+        .find('[rel=alternate]')
         .get()
         .map((i) => {
             i = $(i);
-            return i.attr('href');
+            const url = i.attr('href');
+            try {
+                return new URL(url).toString();
+            } catch (e) {
+                reqUrl.pathname = url;
+                return reqUrl.toString();
+            }
         });
-}
+    return urls;
+};