@bililive-tools/douyu-recorder/lib/dy_api.js

bililive-tools douyu recorder implemention

import crypto from "node:crypto";
import safeEval from "safe-eval";
import { uuid } from "./utils.js";
import queryString from "query-string";
import { requester } from "./requester.js";
/**
 * 对斗鱼 getH5Play 接口的封装
 */
export async function getLiveInfo(opts) {
    const sign = await getSignFn(opts.channelId, opts.rejectSignFnCache);
    const did = uuid().replace(/-/g, "");
    const time = Math.ceil(Date.now() / 1000);
    const signedStr = String(sign(opts.channelId, did, time));
    // TODO: 这里类型处理的有点问题，先用 as 顶着
    // @ts-ignore
    const signed = queryString.parse(signedStr);
    // TODO: 以后可以试试换成 https://open.douyu.com/source/api/9 里提供的公开接口，
    // 不过公开接口可能会存在最高码率的限制。
    const res = await requester.post(`https://www.douyu.com/lapi/live/getH5Play/${opts.channelId}`, new URLSearchParams({
        ...signed,
        cdn: opts.cdn ?? "",
        // 相当于清晰度类型的 id，给 -1 会由后端决定，0为原画
        rate: String(opts.rate ?? 0),
        // 是否只录制音频
        fa: opts.onlyAudio ? "1" : "0",
    }));
    if (res.status !== 200) {
        if (res.status === 403 && res.data === "鉴权失败" && !opts.rejectSignFnCache) {
            // 使用非缓存的sign函数再次签名
            return getLiveInfo({ ...opts, rejectSignFnCache: true });
        }
        throw new Error(`Unexpected status code, ${res.status}, ${res.data}`);
    }
    // TODO: assert data not string
    if (typeof res.data === "string")
        throw new Error();
    const json = res.data;
    // 不存在的房间、已被封禁、未开播
    if ([-3, -4, -5].includes(json.error))
        return { living: false };
    // 其他
    if (json.error !== 0) {
        // 时间戳错误，目前不确定原因，但重新获取几次 sign 函数可解决。
        // TODO: 这里与 getSignFn 隐式的耦合了
        if (json.error === -9)
            delete signCaches[opts.channelId];
        throw new Error("Unexpected error code, " + json.error);
    }
    const streamUrl = `${json.data.rtmp_url}/${json.data.rtmp_live}`;
    let cdn = json.data.rtmp_cdn;
    let onlyAudio = false;
    try {
        const url = new URL(streamUrl);
        cdn = url.searchParams.get("fcdn") ?? "";
        if (url.searchParams.get("only-audio") == "1") {
            onlyAudio = true;
        }
    }
    catch (error) {
        console.warn("解析 rtmp_url 失败", error);
    }
    return {
        living: true,
        sources: json.data.cdnsWithName,
        streams: json.data.multirates,
        isSupportRateSwitch: json.data.rateSwitch === 1,
        isOriginalStream: json.data.rateSwitch !== 1,
        currentStream: {
            onlyAudio,
            source: cdn,
            name: json.data.rateSwitch !== 1
                ? "原画"
                : (json.data.multirates.find(({ rate }) => rate === json.data.rate)?.name ?? "未知"),
            rate: json.data.rate,
            url: streamUrl,
        },
    };
}
// 斗鱼为了判断是否是浏览器环境，会在 sign 过程中去验证一些 window / document 上的函数
// 是否是 native 的，这里利用 proxy 来模拟。
const disguisedNativeMethods = new Proxy({}, {
    get: function () {
        return "function () { [native code] }";
    },
});
const signCaches = {};
async function getSignFn(address, rejectCache) {
    if (!rejectCache && Object.hasOwn(signCaches, address)) {
        // 有缓存, 直接使用
        return signCaches[address];
    }
    const res = await requester.get("https://www.douyu.com/swf_api/homeH5Enc?rids=" + address);
    const json = res.data;
    if (json.error !== 0)
        throw new Error("Unexpected error code, " + json.error);
    const code = json.data && json.data["room" + address];
    if (!code)
        throw new Error("Unexpected result with homeH5Enc, " + JSON.stringify(json));
    const sign = safeEval(`(function func(a,b,c){${code};return ub98484234(a,b,c)})`, {
        CryptoJS: {
            MD5: (str) => {
                return crypto.createHash("md5").update(str).digest("hex");
            },
        },
        window: disguisedNativeMethods,
        document: disguisedNativeMethods,
    });
    signCaches[address] = sign;
    return sign;
}
/**
 * 获取直播间相关信息
 */
export async function getRoomInfo(roomId) {
    const response = await requester.get(`https://www.douyu.com/betard/${roomId}`);
    return response.data;
}