refactor(tmdb): 空结果缓存过期时间收敛为设置项 EMPTY_RESULT_CACHE_TTL

- ConfigModel TMDB 配置区新增 EMPTY_RESULT_CACHE_TTL（默认 30 分钟），支持环境变量覆盖
- request/async_request/discover/TmdbCache 统一改读 settings，移除模块级常量与跨模块导入

app/modules/themoviedb/tmdb_cache.py

@@ -11,7 +11,6 @@ from app.domain.meta.metabase import MetaBase
 from app.runtime.log import logger
 from app.schemas.types import MediaSource, MediaType
 from app.foundation.singleton import WeakSingleton
-from app.modules.themoviedb.tmdbv3api.tmdb import EMPTY_RESULT_CACHE_TTL
 
 lock = RLock()
 PERSISTENCE_VERSION = 1
@@ -262,7 +261,7 @@ class TmdbCache(metaclass=WeakSingleton):
                 # 负识别缓存使用独立的短 TTL：故障期间「合法 JSON 但结果为空」会被
                 # 记为未识别，若按完整有效期固化，故障自愈后同名仍会被判无法识别；
                 # 短过期让恢复后可重新识别，真不存在的条目过期后重新确认一次即可
-                self._set(key, {"id": 0}, ttl=EMPTY_RESULT_CACHE_TTL)
+                self._set(key, {"id": 0}, ttl=settings.EMPTY_RESULT_CACHE_TTL)
 
     def save(self, force: bool = False) -> None:
         """

app/modules/themoviedb/tmdbv3api/objs/discover.py

@@ -1,5 +1,6 @@
 from app.runtime.cache import cached
-from ..tmdb import TMDb, EMPTY_RESULT_CACHE_TTL
+from app.runtime.config import settings
+from ..tmdb import TMDb
 
 try:
     from urllib import urlencode
@@ -13,7 +14,7 @@ class Discover(TMDb):
         "tv": "/discover/tv"
     }
 
-    @cached(maxsize=1, ttl=43200, empty_ttl=EMPTY_RESULT_CACHE_TTL)
+    @cached(maxsize=1, ttl=43200, empty_ttl=settings.EMPTY_RESULT_CACHE_TTL)
     def discover_movies(self, params_tuple):
         """
         Discover movies by different types of data like average rating, number of votes, genres and certifications.
@@ -23,7 +24,7 @@ class Discover(TMDb):
         params = dict(params_tuple)
         return self._request_obj(self._urls["movies"], urlencode(params), key="results", call_cached=False)
 
-    @cached(maxsize=1, ttl=43200, empty_ttl=EMPTY_RESULT_CACHE_TTL)
+    @cached(maxsize=1, ttl=43200, empty_ttl=settings.EMPTY_RESULT_CACHE_TTL)
     def discover_tv_shows(self, params_tuple):
         """
         Discover TV shows by different types of data like average rating, number of votes, genres,
@@ -33,7 +34,7 @@ class Discover(TMDb):
         """
         return self._request_obj(self._urls["tv"], urlencode(params_tuple), key="results", call_cached=False)
 
-    @cached(maxsize=1, ttl=43200, empty_ttl=EMPTY_RESULT_CACHE_TTL)
+    @cached(maxsize=1, ttl=43200, empty_ttl=settings.EMPTY_RESULT_CACHE_TTL)
     async def async_discover_movies(self, params_tuple):
         """
         Discover movies by different types of data like average rating, number of votes, genres and certifications.（异步版本）
@@ -43,7 +44,7 @@ class Discover(TMDb):
         params = dict(params_tuple)
         return await self._async_request_obj(self._urls["movies"], urlencode(params), key="results", call_cached=False)
 
-    @cached(maxsize=1, ttl=43200, empty_ttl=EMPTY_RESULT_CACHE_TTL)
+    @cached(maxsize=1, ttl=43200, empty_ttl=settings.EMPTY_RESULT_CACHE_TTL)
     async def async_discover_tv_shows(self, params_tuple):
         """
         Discover TV shows by different types of data like average rating, number of votes, genres,

app/modules/themoviedb/tmdbv3api/tmdb.py

@@ -22,11 +22,6 @@ logger = logging.getLogger(__name__)
 # 故取区间内的经验值。
 RETRY_BACKOFF_SECONDS = 2
 
-# 空结果缓存的独立过期时间（秒）。TMDB 代理故障期间「合法 JSON 但 results 为空」的
-# 响应会随默认 TTL（可达数十小时）固化，故障自愈后同 key 仍持续命中空结果；空结果
-# 改用 30 分钟短 TTL，既能拦住故障窗口内的重复回源，又能在故障恢复后较快自然失效。
-EMPTY_RESULT_CACHE_TTL = 30 * 60
-
 
 def _is_business_failure_snapshot(snapshot) -> bool:
     """
@@ -47,8 +42,8 @@ def _is_empty_result_snapshot(snapshot) -> bool:
     判断响应快照是否为空结果（列表/搜索类接口的 results 为空列表）。
 
     这类快照结构合法但无业务内容，常由代理瞬时故障产生；不能靠 skip_none/skip_empty
-    识别（快照本身是非空字典），需单独谓词判定后按 EMPTY_RESULT_CACHE_TTL 短 TTL
-    缓存。详情类接口无 results 字段，不属于空结果。
+    识别（快照本身是非空字典），需单独谓词判定后按 settings.EMPTY_RESULT_CACHE_TTL
+    短 TTL 缓存。详情类接口无 results 字段，不属于空结果。
     """
     if not isinstance(snapshot, dict):
         return False
@@ -180,7 +175,7 @@ class TMDb(object):
 
     @cached(maxsize=settings.CONF.tmdb, ttl=settings.CONF.meta, skip_none=True,
             skip_if=_is_business_failure_snapshot,
-            empty_ttl=EMPTY_RESULT_CACHE_TTL, empty_if=_is_empty_result_snapshot)
+            empty_ttl=settings.EMPTY_RESULT_CACHE_TTL, empty_if=_is_empty_result_snapshot)
     def request(self, method, url, data, json, **kwargs):
         req = self._request_once(method, url, data, json)
         if req is None and method == "GET" and self._owns_session:
@@ -206,7 +201,7 @@ class TMDb(object):
 
     @cached(maxsize=settings.CONF.tmdb, ttl=settings.CONF.meta, skip_none=True,
             skip_if=_is_business_failure_snapshot,
-            empty_ttl=EMPTY_RESULT_CACHE_TTL, empty_if=_is_empty_result_snapshot)
+            empty_ttl=settings.EMPTY_RESULT_CACHE_TTL, empty_if=_is_empty_result_snapshot)
     async def async_request(self, method, url, data, json, **kwargs):
         req = await self._async_request_once(method, url, data, json)
         if req is None:

app/runtime/config.py

@@ -255,6 +255,8 @@ class ConfigModel(BaseModel):
     TMDB_API_DOMAIN: str = "api.themoviedb.org"
     # TMDB元数据语言
     TMDB_LOCALE: str = "zh"
+    # TMDB空结果缓存独立过期时间（秒），故障期间产生的空响应快速过期，故障自愈后可自然恢复
+    EMPTY_RESULT_CACHE_TTL: int = 30 * 60
     # 刮削使用TMDB原始语种图片
     TMDB_SCRAP_ORIGINAL_IMAGE: bool = False
     # TMDB API Key

tests/test_tmdb_cache_type_guard.py

@@ -3,7 +3,6 @@ from types import SimpleNamespace
 
 from app.runtime.config import settings
 from app.modules.themoviedb.tmdb_cache import TmdbCache
-from app.modules.themoviedb.tmdbv3api.tmdb import EMPTY_RESULT_CACHE_TTL
 from app.schemas.types import MediaSource, MediaType
 
 
@@ -133,9 +132,9 @@ def test_update_negative_cache_uses_short_ttl():
 
     key = _key("电视剧")
     assert cache._cache.data[key] == {"id": 0}
-    assert cache._cache.ttls[key] == EMPTY_RESULT_CACHE_TTL
+    assert cache._cache.ttls[key] == settings.EMPTY_RESULT_CACHE_TTL
     # 持久化用的过期时间也应随短 TTL 计算，不能沿用默认有效期
-    assert cache._expires_at[key] <= time() + EMPTY_RESULT_CACHE_TTL + 5
+    assert cache._expires_at[key] <= time() + settings.EMPTY_RESULT_CACHE_TTL + 5
 
 
 def test_update_positive_cache_keeps_default_ttl():

tests/test_tmdb_empty_result_cache.py

@@ -9,11 +9,11 @@ import asyncio
 from unittest.mock import patch
 
 from app.modules.themoviedb.tmdbv3api.tmdb import (
-    EMPTY_RESULT_CACHE_TTL,
     TMDb,
     _is_empty_result_snapshot,
 )
 from app.runtime.cache import MemoryBackend
+from app.runtime.config import settings
 
 from tests.test_tmdb_response_cache import _FakeResponse
 
@@ -41,7 +41,7 @@ def _make_tmdb() -> TMDb:
 
 def test_empty_result_cache_ttl_is_thirty_minutes():
     """空结果缓存的独立过期时间应为 30 分钟。"""
-    assert EMPTY_RESULT_CACHE_TTL == 30 * 60
+    assert settings.EMPTY_RESULT_CACHE_TTL == 30 * 60
 
 
 def test_empty_result_snapshot_predicate():
@@ -67,7 +67,7 @@ def test_empty_result_is_cached_but_expires_with_short_ttl():
 
     region_cache = _request_region_cache()
     started_at = region_cache.timer()
-    region_cache.expire(time=started_at + EMPTY_RESULT_CACHE_TTL + 1)
+    region_cache.expire(time=started_at + settings.EMPTY_RESULT_CACHE_TTL + 1)
 
     with patch.object(TMDb, "_request_once", return_value=fake) as req:
         tmdb.request("GET", url, None, None)
@@ -87,7 +87,7 @@ def test_non_empty_result_keeps_default_ttl():
     region_cache = _request_region_cache()
     started_at = region_cache.timer()
     # 推进到短 TTL 之后：非空结果不应在此刻过期
-    region_cache.expire(time=started_at + EMPTY_RESULT_CACHE_TTL + 1)
+    region_cache.expire(time=started_at + settings.EMPTY_RESULT_CACHE_TTL + 1)
 
     tmdb.request("GET", url, None, None)
     assert req.call_count == 1
@@ -106,7 +106,7 @@ def test_async_empty_result_is_cached_with_short_ttl():
 
     region_cache = _request_region_cache()
     started_at = region_cache.timer()
-    region_cache.expire(time=started_at + EMPTY_RESULT_CACHE_TTL + 1)
+    region_cache.expire(time=started_at + settings.EMPTY_RESULT_CACHE_TTL + 1)
 
     with patch.object(TMDb, "_async_request_once", return_value=fake) as req:
         asyncio.run(tmdb.async_request("GET", url, None, None))