fix: remove stale _decimal_str ref, add context manager to HTTP clients

- UpstreamClient & Sub2ApiWebsiteClient: add __enter__/__exit__
- Convert all call sites to `with Client(...) as c:` pattern
- Remove unused `upstream_name`/`upstream_base_url` locals in scheduler
- Fix stale _decimal_str→decimal_string in _rate_from_group

backend/app/routers/upstreams.py

@@ -146,13 +146,13 @@ def test_upstream(uid: int, db: Session = Depends(get_db), _=Depends(get_current
     if not u:
         raise HTTPException(404, "upstream not found")
     auth_config = json.loads(u.auth_config_json or "{}")
-    client = UpstreamClient(
+    with UpstreamClient(
         base_url=u.base_url,
         api_prefix=u.api_prefix,
         auth_type=u.auth_type,
         auth_config=auth_config,
         timeout=float(u.timeout_seconds),
-    )
+    ) as client:
         try:
             client.login()
             groups = client.get_available_groups(u.groups_endpoint)
@@ -177,13 +177,13 @@ def check_now(uid: int, db: Session = Depends(get_db), _=Depends(get_current_use
     if not u:
         raise HTTPException(404, "upstream not found")
     auth_config = json.loads(u.auth_config_json or "{}")
-    client = UpstreamClient(
+    with UpstreamClient(
         base_url=u.base_url,
         api_prefix=u.api_prefix,
         auth_type=u.auth_type,
         auth_config=auth_config,
         timeout=float(u.timeout_seconds),
-    )
+    ) as client:
         try:
             client.login()
             groups = client.get_available_groups(u.groups_endpoint)

backend/app/routers/websites.py

@@ -188,7 +188,8 @@ def test_website(wid: int, db: Session = Depends(get_db), _=Depends(get_current_
     if not row:
         raise HTTPException(404, "website not found")
     try:
-        groups = _client(row).get_groups(row.groups_endpoint)
+        with _client(row) as c:
+            groups = c.get_groups(row.groups_endpoint)
         row.last_status = "healthy"
         row.last_error = None
         row.last_checked_at = datetime.now(timezone.utc)
@@ -208,7 +209,8 @@ def list_website_groups(wid: int, db: Session = Depends(get_db), _=Depends(get_c
     if not row:
         raise HTTPException(404, "website not found")
     try:
-        return _client(row).get_groups(row.groups_endpoint)
+        with _client(row) as c:
+            return c.get_groups(row.groups_endpoint)
     except Exception as exc:
         raise HTTPException(502, str(exc))
 

backend/app/services/scheduler.py

@@ -37,7 +37,6 @@ def _check_upstream(upstream_id: int) -> None:
     settings = get_settings()
     # ── Phase 1: upstream check + DB write ──────────────────────────
     db: Session = SessionLocal()
-    client = None
     try:
         upstream = db.query(Upstream).filter(Upstream.id == upstream_id).first()
         if not upstream or not upstream.enabled:
@@ -45,18 +44,17 @@ def _check_upstream(upstream_id: int) -> None:
             return
 
         auth_config = json.loads(upstream.auth_config_json or "{}")
-        client = UpstreamClient(
+        was_unhealthy = upstream.last_status == "unhealthy"
+        snapshot = None
+        changes = None
+
+        with UpstreamClient(
             base_url=upstream.base_url,
             api_prefix=upstream.api_prefix,
             auth_type=upstream.auth_type,
             auth_config=auth_config,
             timeout=float(upstream.timeout_seconds),
-        )
+        ) as client:
-
-        was_unhealthy = upstream.last_status == "unhealthy"
-        snapshot = None
-        changes = None
-
             try:
                 client.login()
                 groups = client.get_available_groups(upstream.groups_endpoint)
@@ -84,7 +82,7 @@ def _check_upstream(upstream_id: int) -> None:
                                    "upstream_unhealthy", str(exc))
                 return
 
-        # success path
+        # success path (client auto-closed by `with`)
         prev_snapshot_row = (
             db.query(UpstreamRateSnapshot)
             .filter(UpstreamRateSnapshot.upstream_id == upstream_id)
@@ -116,7 +114,6 @@ def _check_upstream(upstream_id: int) -> None:
         )
 
     finally:
-        client.close()
         db.close()
 
     # ── Phase 2: notifications (independent sessions) ──────────────

backend/app/services/upstream_client.py

@@ -83,7 +83,7 @@ def _rate_from_group(group: dict[str, Any]) -> str:
         "effective_rate_multiplier", "effectiveRateMultiplier",
         "rate_multiplier", "rateMultiplier",
     ):
-        r = _decimal_str(group.get(key))
+        r = decimal_string(group.get(key))
         if r:
             return r
     return ""
@@ -214,6 +214,12 @@ class UpstreamClient:
     def close(self) -> None:
         self._client.close()
 
+    def __enter__(self) -> UpstreamClient:
+        return self
+
+    def __exit__(self, *args: Any) -> None:
+        self.close()
+
     def _url(self, path: str) -> str:
         prefix = f"/{self.api_prefix}" if self.api_prefix else ""
         return f"{self.base_url}{prefix}/{path.lstrip('/')}"

backend/app/services/website_client.py

@@ -105,6 +105,12 @@ class Sub2ApiWebsiteClient:
     def close(self) -> None:
         self._client.close()
 
+    def __enter__(self) -> Sub2ApiWebsiteClient:
+        return self
+
+    def __exit__(self, *args: Any) -> None:
+        self.close()
+
     def _url(self, path: str) -> str:
         prefix = f"/{self.api_prefix}" if self.api_prefix else ""
         return f"{self.base_url}{prefix}/{path.lstrip('/')}"

backend/app/services/website_sync.py

@@ -118,7 +118,7 @@ def sync_binding(db: Session, binding: WebsiteGroupBinding, write: bool = True)
     old_rate = None
     if write and website.enabled and website.auto_sync_enabled and binding.enabled:
         try:
-            client = _client_for(website)
+            with _client_for(website) as client:
                 groups = client.get_groups(website.groups_endpoint)
                 target = next((item for item in groups if item.get("id") == binding.target_group_id), None)
                 old_rate = target.get("rate_multiplier") if target else None

backend/test_upstream.py

@@ -6,13 +6,13 @@ from app.services.upstream_client import UpstreamClient
 logging.basicConfig(level=logging.DEBUG)
 
 def main():
-    client = UpstreamClient(
+    with UpstreamClient(
         base_url="http://170.106.100.210:55555",
         api_prefix="",
         auth_type="bearer",
         auth_config={"token": ""},  # We don't have token, but /api/group/ in some new-api may be open, or fail with 401
         timeout=10.0,
-    )
+    ) as client:
         try:
             groups = client.get_available_groups("/api/group/")
             print("Groups:", groups)