add bilibili video danmaku (#1478)

docs/README.md

@@ -297,6 +297,8 @@ RSSHub 提供下列 API 接口:
 
 <route name="视频评论" author="Qixingchen" example="/bilibili/video/reply/21669336" path="/bilibili/video/reply/:aid" :paramsDesc="['可在视频页 URL 中找到']"/>
 
+<route name="视频弹幕" author="Qixingchen" example="/bilibili/video/danmaku/21669336/1" path="/bilibili/video/danmaku/:aid/:pid?" :paramsDesc="['视频AV号,可在视频页 URL 中找到','分P号,不填默认为1']"/>
+
 <route name="link 公告" author="Qixingchen" example="/bilibili/link/news/live" path="/bilibili/link/news/:product" :paramsDesc="['公告分类, 包括 直播:live 小视频:vc 相簿:wh']"/>
 
 #### 直播开播 <Author uid="Qixingchen"/>

lib/router.js

@@ -123,6 +123,7 @@ router.get('/bilibili/partion/ranking/:tid/:days?', require('./routes/bilibili/p
 router.get('/bilibili/bangumi/:seasonid', require('./routes/bilibili/bangumi')); // 弃用
 router.get('/bilibili/bangumi/media/:mediaid', require('./routes/bilibili/bangumi'));
 router.get('/bilibili/video/reply/:aid', require('./routes/bilibili/reply'));
+router.get('/bilibili/video/danmaku/:aid/:pid?', require('./routes/bilibili/danmaku'));
 router.get('/bilibili/link/news/:product', require('./routes/bilibili/linkNews'));
 router.get('/bilibili/live/room/:roomID', require('./routes/bilibili/liveRoom'));
 router.get('/bilibili/live/search/:key/:order', require('./routes/bilibili/liveSearch'));

lib/routes/bilibili/cache.js

@@ -102,4 +102,24 @@ module.exports = {
         }
         return name;
     },
+    getCidFromAid: async (ctx, aid, pid) => {
+        const key = `bili-Cid-from-Aid-${aid}-${pid}`;
+        let cid = await ctx.cache.get(key);
+        if (!cid) {
+            const cidResponse = await axios({
+                method: 'get',
+                url: `https://api.bilibili.com/x/web-interface/view?aid=${aid}`,
+                headers: {
+                    Referer: `https://www.bilibili.com/video/av${aid}`,
+                },
+            });
+            if (cidResponse && cidResponse.data && cidResponse.data.data && cidResponse.data.data.pages && cidResponse.data.data.pages.length >= pid) {
+                cid = cidResponse.data.data.pages[pid - 1].cid;
+            }
+            if (!cid) {
+                ctx.cache.set(key, cid, 24 * 60 * 60);
+            }
+        }
+        return cid;
+    },
 };

lib/routes/bilibili/danmaku.js

@@ -0,0 +1,35 @@
+const cheerio = require('cheerio');
+const cache = require('./cache');
+const fetch = require('node-fetch');
+
+module.exports = async (ctx) => {
+    const aid = ctx.params.aid;
+    const pid = Number(ctx.params.pid || 1);
+    const limit = 50;
+    const cid = await cache.getCidFromAid(ctx, aid, pid);
+
+    const videoName = await cache.getVideoNameFromAid(ctx, aid);
+
+    const danmakuResponse = await fetch(`https://comment.bilibili.com/${cid}.xml`);
+    const danmakuText = await danmakuResponse.text();
+    let danmakuList = [];
+    const $ = cheerio.load(danmakuText, { xmlMode: true });
+    $('d').each((index, item) => {
+        danmakuList.push({ p: $(item).attr('p'), text: $(item).text() });
+    });
+
+    danmakuList = danmakuList.reverse().slice(0, limit);
+
+    ctx.state.data = {
+        title: `${videoName} 的 弹幕动态`,
+        link: `https://www.bilibili.com/video/av${aid}`,
+        description: `${videoName} 的 弹幕动态`,
+        item: danmakuList.map((item) => ({
+            title: item.text,
+            description: item.text,
+            pubDate: new Date(item.p.split(',')[4] * 1000).toUTCString(),
+            guid: `${cid}-${item.p.split(',')[4]}-${item.p.split(',')[7]}`,
+            link: `https://www.bilibili.com/video/av${aid}`,
+        })),
+    };
+};

package.json

@@ -67,6 +67,7 @@
     "lru-cache": "5.1.1",
     "luxon": "^1.7.1",
     "markdown-it": "^8.4.2",
+    "node-fetch": "^2.3.0",
     "path-to-regexp": "3.0.0",
     "pidusage": "^2.0.17",
     "plist": "^3.0.1",