refactor(douyin): 多源轮询解析重构，删除yt-dlp/cookies死代码

- 新建 douyin_resolver.py: P0 App Feed API(免费) → P1 TikHub → P2 apizero → P3 GoDownloader
- 删除 yt-dlp、cookies、ttwid、HTML直抓等已失效的死代码
- scripts_ai.py 大幅精简：resolver → MediaKit ASR → 本地下载ASR → desc兜底
- 图文视频/无旁白视频统一在resolver层识别并处理
- 错误信息保持分阶段（解析/下载/ASR），不暴露内部细节
- 未配置第三方API Key时P0免费源仍可正常工作
- 新增 TIKHUB_API_KEY/APIZERO_API_KEY/RAPIDAPI_KEY 环境变量
- __debug_diag 接口改为报告各源可用状态

.env.example

@@ -203,3 +203,16 @@ DOUBAO_MAX_RETRIES=2
 #   `if settings.points_enabled: ...`
 # 包裹扣点逻辑；所有路由接入完成并验证通过后再在 staging/prod 打开。
 POINTS_ENABLED=false
+
+# ==================== 抖音解析多源轮询 (#1963) ====================
+# P0 App Feed API（免费，默认启用）→ P1 TikHub → P2 apizero → P3 GoDownloader
+# 无需配置 Key 也可使用（P0 免费源可用），配置 Key 可增加兜底能力
+
+# TikHub API Key (https://tikhub.io) — $0.001/次起，注册送$0.05
+TIKHUB_API_KEY=
+
+# apizero.cn API Key (https://v1.apizero.cn) — 国内抖音解析服务
+APIZERO_API_KEY=
+
+# RapidAPI Key (https://rapidapi.com) — 订阅 GoDownloader 免费层（60次/分）
+RAPIDAPI_KEY=

apps/api/app/services/douyin_resolver.py

@@ -0,0 +1,275 @@
+"""抖音视频解析多源轮询服务。
+
+优先级（P0 最高）：
+  P0: App Feed API 直连（零成本，不用 API Key，当前最稳定）
+  P1: TikHub API（付费 $0.001/次起，稳定）
+  P2: apizero.cn 极数本源（按量付费，国内延迟低）
+  P3: GoDownloader / RapidAPI（免费层 60 次/分兜底）
+
+任一源成功即返回 MP4 直链 + 标题/文案；所有源均失败时返回 None。
+每个解析源独立超时（5-8s），总耗时不超过所有源超时之和（实际快速失败时远小于此）。
+未配置 API Key 的源自动跳过；无任何 Key 时 P0 仍可使用。
+"""
+
+from __future__ import annotations
+
+import logging
+import os
+import re
+import time
+from dataclasses import dataclass
+from typing import Optional
+
+import httpx
+
+logger = logging.getLogger(__name__)
+
+# ── API Keys from env ──────────────────────────────────────────────────
+TIKHUB_API_KEY = os.environ.get("TIKHUB_API_KEY", "").strip()
+APIZERO_API_KEY = os.environ.get("APIZERO_API_KEY", "").strip()
+RAPIDAPI_KEY = os.environ.get("RAPIDAPI_KEY", "").strip()
+
+# ── Timeouts (seconds) ────────────────────────────────────────────────
+_TIMEOUT_APP_FEED = 10
+_TIMEOUT_TIKHUB = 5
+_TIMEOUT_APIZERO = 5
+_TIMEOUT_GODOWNLOADER = 8
+
+
+@dataclass
+class ResolveResult:
+    video_url: str  # MP4 直链；图文视频时为空字符串
+    desc: str  # 视频标题/描述文案
+    source: str  # 解析源名称，用于日志/metrics
+
+
+# ── URL preprocessing ─────────────────────────────────────────────────
+_AWEME_ID_RE = re.compile(
+    r"(?:douyin\.com/(?:video|note)/|iesdouyin\.com/share/video/|aweme_id=)(\d{15,25})",
+    re.IGNORECASE,
+)
+
+
+def _extract_url_from_text(text: str) -> str:
+    """从任意分享文本中提取首个 http(s) URL。"""
+    if not text:
+        return ""
+    m = re.search(r"https?://\S+", text)
+    return m.group(0).rstrip("。，！？!?,，；;\"'）)】") if m else ""
+
+
+def _canonicalize_url(url: str, timeout: int = 8) -> str:
+    """跟随 v.douyin.com 短链 302 重定向，返回完整 URL。失败时返回原 URL。"""
+    if "v.douyin.com" not in url and "iesdouyin.com" not in url:
+        return url
+    try:
+        with httpx.Client(timeout=timeout, follow_redirects=True, verify=False,
+                          headers={"User-Agent": "Mozilla/5.0"}) as c:
+            resp = c.get(url)
+            return str(resp.url)
+    except Exception as exc:
+        logger.debug("短链解析失败: %s (%s)", url, exc)
+        return url
+
+
+# ── Provider P0: App Feed API (零成本直连) ────────────────────────────
+def _resolve_app_feed(url: str, timeout: int = _TIMEOUT_APP_FEED) -> Optional[ResolveResult]:
+    """抖音 Android App Feed API 直连 — 零依赖、无需 Key、目前最稳定。"""
+    from packages.douyin_parser import fetch_douyin_video_url
+
+    video_url, desc = fetch_douyin_video_url(url, timeout=timeout, max_retries=2)
+    if video_url:
+        return ResolveResult(video_url=video_url, desc=desc or "", source="app_feed")
+    if desc:
+        # 图文视频：video_url 为 None 但 desc 可用
+        return ResolveResult(video_url="", desc=desc, source="app_feed_image")
+    return None
+
+
+# ── Provider P1: TikHub ───────────────────────────────────────────────
+def _resolve_tikhub(url: str, api_key: str, timeout: int = _TIMEOUT_TIKHUB) -> Optional[ResolveResult]:
+    """TikHub API: https://api.tikhub.io/
+    两步：get_aweme_id → fetch_one_video
+    """
+    if not api_key:
+        return None
+    headers = {"Authorization": f"Bearer {api_key}"}
+    aweme_id = _AWEME_ID_RE.search(url or "")
+    aweme_id = aweme_id.group(1) if aweme_id else None
+
+    if not aweme_id:
+        try:
+            with httpx.Client(timeout=timeout, verify=False) as c:
+                r = c.get(
+                    "https://api.tikhub.io/api/v1/douyin/web/get_aweme_id",
+                    headers=headers, params={"url": url},
+                )
+                data = r.json()
+                aweme_id = (data.get("data") or {}).get("aweme_id")
+        except Exception as exc:
+            logger.warning("TikHub get_aweme_id 失败: %s", exc)
+            return None
+    if not aweme_id:
+        return None
+
+    try:
+        with httpx.Client(timeout=timeout, verify=False) as c:
+            r = c.get(
+                "https://api.tikhub.io/api/v1/douyin/app/v3/fetch_one_video",
+                headers=headers, params={"aweme_id": aweme_id},
+            )
+            data = r.json()
+            video = ((data.get("data") or {}).get("video") or {})
+            urls = []
+            for k in ("download_addr", "play_addr_h264", "play_addr"):
+                urls = (video.get(k) or {}).get("url_list") or []
+                if urls:
+                    break
+            if not urls:
+                # bit_rate 兜底
+                for br in video.get("bit_rate") or []:
+                    urls = (br.get("play_addr") or {}).get("url_list") or []
+                    if urls:
+                        break
+            if not urls:
+                return None
+            # 优先 CDN 直链
+            video_url = urls[0]
+            for u in urls:
+                if any(h in u for h in ("douyinvod.com", "bytecdn.com", "365yg.com")):
+                    video_url = u
+                    break
+            desc = (data.get("data") or {}).get("desc", "")
+            # 检测图文
+            images = (data.get("data") or {}).get("images") or []
+            if images and not any(h in video_url for h in ("douyinvod.com", "bytecdn.com", "amemv.com")):
+                # 图文且无视频直链
+                if desc:
+                    return ResolveResult(video_url="", desc=desc, source="tikhub_image")
+                return None
+            return ResolveResult(video_url=video_url, desc=desc or "", source="tikhub")
+    except Exception as exc:
+        logger.warning("TikHub fetch_one_video 失败: %s", exc)
+        return None
+
+
+# ── Provider P2: apizero.cn ──────────────────────────────────────────
+def _resolve_apizero(url: str, api_key: str, timeout: int = _TIMEOUT_APIZERO) -> Optional[ResolveResult]:
+    """apizero.cn 极数本源: https://v1.apizero.cn/api/video-parse?url=...&flat=2"""
+    if not api_key:
+        return None
+    headers = {"Authorization": f"Bearer {api_key}"}
+    try:
+        with httpx.Client(timeout=timeout, verify=False) as c:
+            r = c.get(
+                "https://v1.apizero.cn/api/video-parse",
+                headers=headers, params={"url": url, "flat": 2},
+            )
+            data = r.json()
+            d = data.get("data") or {}
+            video_list = d.get("video_list") or []
+            if not video_list:
+                return None
+            video_url = video_list[0].get("url", "")
+            desc = d.get("title", "") or d.get("desc", "") or d.get("author", "")
+            if not video_url:
+                return None
+            return ResolveResult(video_url=video_url, desc=desc, source="apizero")
+    except Exception as exc:
+        logger.warning("apizero 解析失败: %s", exc)
+        return None
+
+
+# ── Provider P3: GoDownloader (RapidAPI) ──────────────────────────────
+def _resolve_godownloader(url: str, api_key: str, timeout: int = _TIMEOUT_GODOWNLOADER) -> Optional[ResolveResult]:
+    """GoDownloader via RapidAPI"""
+    if not api_key:
+        return None
+    headers = {
+        "X-RapidAPI-Key": api_key,
+        "X-RapidAPI-Host": "tiktok-download-video-no-watermark.p.rapidapi.com",
+    }
+    try:
+        with httpx.Client(timeout=timeout, verify=False) as c:
+            r = c.get(
+                "https://tiktok-download-video-no-watermark.p.rapidapi.com/auto",
+                headers=headers, params={"url": url},
+            )
+            data = r.json()
+            video_url = (
+                (data.get("video") or {}).get("url")
+                or data.get("video_no_watermark")
+                or data.get("nwm_video_url")
+                or ""
+            )
+            desc = data.get("title", "") or data.get("desc", "")
+            if not video_url:
+                return None
+            return ResolveResult(video_url=video_url, desc=desc, source="godownloader")
+    except Exception as exc:
+        logger.warning("GoDownloader 解析失败: %s", exc)
+        return None
+
+
+# ── Main API ──────────────────────────────────────────────────────────
+def resolve_douyin_video(page_url: str) -> Optional[ResolveResult]:
+    """按 P0→P1→P2→P3 顺序轮询解析抖音视频。
+
+    Args:
+        page_url: 抖音 URL 或含 URL 的分享文本。
+
+    Returns:
+        ResolveResult 或 None（所有源均失败）。
+        图文视频时 video_url 为空字符串、desc 为文案。
+    """
+    url = _extract_url_from_text(page_url) or page_url
+    url = _canonicalize_url(url)
+
+    providers = [
+        ("app_feed", lambda: _resolve_app_feed(url)),
+        ("tikhub", lambda: _resolve_tikhub(url, TIKHUB_API_KEY)),
+        ("apizero", lambda: _resolve_apizero(url, APIZERO_API_KEY)),
+        ("godownloader", lambda: _resolve_godownloader(url, RAPIDAPI_KEY)),
+    ]
+
+    enabled_count = 0
+    for name, fn in providers:
+        if name == "tikhub" and not TIKHUB_API_KEY:
+            continue
+        if name == "apizero" and not APIZERO_API_KEY:
+            continue
+        if name == "godownloader" and not RAPIDAPI_KEY:
+            continue
+        enabled_count += 1
+        t0 = time.time()
+        try:
+            result = fn()
+            elapsed = time.time() - t0
+            if result:
+                domain = result.video_url.split("/")[2] if result.video_url and "/" in result.video_url else "(image)"
+                logger.info(
+                    "抖音解析成功: source=%s url_domain=%s desc_len=%d time=%.2fs",
+                    result.source, domain, len(result.desc), elapsed,
+                )
+                return result
+            logger.debug("解析源 %s 返回空 (%.2fs)", name, elapsed)
+        except Exception as exc:
+            logger.warning("解析源 %s 异常 (%.2fs): %s", name, time.time() - t0, exc)
+
+    if enabled_count == 0:
+        logger.error("无任何抖音解析源可用：请检查 App Feed API 网络连通性")
+    else:
+        logger.warning("所有 %d 个抖音解析源均失败: url=%s", enabled_count, url)
+    return None
+
+
+def available_providers() -> list[str]:
+    """返回当前可用的解析源列表（用于诊断）。"""
+    provs = ["app_feed"]
+    if TIKHUB_API_KEY:
+        provs.append("tikhub")
+    if APIZERO_API_KEY:
+        provs.append("apizero")
+    if RAPIDAPI_KEY:
+        provs.append("godownloader")
+    return provs