fix: serve frontend js with javascript mime (#1808)

api/app.py

@@ -42,7 +42,12 @@ _INDEX_ASSET_REF_PATTERN = re.compile(
     r"""(?:src|href)\s*=\s*["'](/assets/[^"']+)["']""",
     re.IGNORECASE,
 )
-_SAFE_MISSING_ASSET_MEDIA_TYPES = frozenset({"text/css", "text/javascript"})
+_FRONTEND_ASSET_MEDIA_TYPES = {
+    ".css": "text/css",
+    ".js": "text/javascript",
+    ".mjs": "text/javascript",
+}
+_SAFE_MISSING_ASSET_MEDIA_TYPES = frozenset(_FRONTEND_ASSET_MEDIA_TYPES.values())
 _FRONTEND_INDEX_NO_CACHE_HEADERS = {
     "Cache-Control": "no-store, no-cache, must-revalidate, max-age=0",
     "Pragma": "no-cache",
@@ -116,9 +121,23 @@ def _resolve_asset_path(assets_dir: Path, asset_path: str) -> Optional[Path]:
     return candidate
 
 
+def _register_frontend_asset_mime_types() -> None:
+    """Keep Vite module assets loadable even when OS MIME maps are wrong."""
+    for suffix, media_type in _FRONTEND_ASSET_MEDIA_TYPES.items():
+        mimetypes.add_type(media_type, suffix)
+
+
+def _frontend_asset_media_type(asset_path: str) -> Optional[str]:
+    suffix = Path(asset_path).suffix.lower()
+    if suffix in _FRONTEND_ASSET_MEDIA_TYPES:
+        return _FRONTEND_ASSET_MEDIA_TYPES[suffix]
+    content_type, _ = mimetypes.guess_type(asset_path)
+    return content_type
+
+
 def _missing_asset_media_type(asset_path: str) -> str:
     """Return a safe media type for a missing asset response."""
-    content_type, _ = mimetypes.guess_type(asset_path)
+    content_type = _frontend_asset_media_type(asset_path)
     if content_type in _SAFE_MISSING_ASSET_MEDIA_TYPES:
         return content_type
     return "text/plain"
@@ -286,6 +305,8 @@ def create_app(static_dir: Optional[Path] = None) -> FastAPI:
         配置完成的 FastAPI 应用实例
     """
     # 默认静态文件目录
+    _register_frontend_asset_mime_types()
+
     if static_dir is None:
         static_dir = Path(__file__).parent.parent / "static"
     
@@ -516,7 +537,7 @@ def create_app(static_dir: Optional[Path] = None) -> FastAPI:
                     return _frontend_index_response(static_dir)
                 # Issue #520: Explicitly resolve MIME type to avoid
                 # browsers rejecting JS modules served as text/plain.
-                content_type, _ = mimetypes.guess_type(str(file_path))
+                content_type = _frontend_asset_media_type(str(file_path))
                 return FileResponse(file_path, media_type=content_type)
 
             return _frontend_index_response(static_dir)

docs/CHANGELOG.md

@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 - [修复] 将 Docker 可安装的 Longbridge SDK 版本固定为 0.2.75，避免 `longbridge>=0.2.77` 从包索引消失后导致 docker-build 失败。
 
 - [修复] 默认通知报告补充展示 `dashboard.phase_decision` 盘中决策护栏字段，避免与模板渲染路径展示不一致。
+- [修复] 修复 Windows 环境下 Web/Desktop 静态 JS 资源可能被识别为 `text/plain` 导致前端黑屏的问题。
 - [改进] Web 设置页新增首次启动配置检查卡，串联基础配置状态、自选股入口、模型配置入口和一次简短试跑。
 - [改进] 通知报告的分析结果摘要不再展开 AI 决策信号明细，完整信号保留在个股详情和单股报告中。
 - [新功能] #1595 P1.5 新增 Provider Cache Capability Registry，按 provider、api surface、gateway 和 verification status 建模 prompt cache 能力，未知 OpenAI-compatible route 默认 telemetry only。

tests/test_static_assets_consistency.py

@@ -14,6 +14,7 @@ from __future__ import annotations
 import importlib
 import json
 import logging
+import mimetypes
 import os
 import sys
 from pathlib import Path
@@ -205,6 +206,29 @@ def test_existing_asset_is_served_from_explicit_assets_route(tmp_path: Path) ->
     assert css_response.headers["content-type"].startswith("text/css")
 
 
+def test_existing_js_asset_overrides_bad_system_mime_mapping(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    from api.app import create_app
+
+    monkeypatch.setitem(mimetypes.types_map, ".js", "text/plain")
+    monkeypatch.setitem(mimetypes.common_types, ".js", "text/plain")
+
+    static_dir = tmp_path / "static"
+    assets_dir = static_dir / "assets"
+    assets_dir.mkdir(parents=True)
+    js_file = assets_dir / "index-abc.js"
+    js_file.write_text("console.log('ok')", encoding="utf-8")
+    (assets_dir / "index-abc.css").write_text("body{color:#fff}", encoding="utf-8")
+    _write_index(static_dir, _vite_index("index-abc.js", "index-abc.css"))
+
+    client = TestClient(create_app(static_dir=static_dir))
+
+    js_response = client.get("/assets/index-abc.js")
+
+    assert js_response.status_code == 200
+    assert js_response.text == "console.log('ok')"
+    assert js_response.headers["content-type"].startswith("text/javascript")
+
+
 def test_existing_asset_supports_head_and_conditional_requests(tmp_path: Path) -> None:
     from api.app import create_app