merge: testing → main (reconcile 2-week divergence)

decnet/web/router/logs/api_get_histogram.py

@@ -1,20 +1,58 @@
+import asyncio
+import time
 from typing import Any, Optional
 
 from fastapi import APIRouter, Depends, Query
 
-from decnet.web.dependencies import get_current_user, repo
+from decnet.telemetry import traced as _traced
+from decnet.web.dependencies import require_viewer, repo
 
 router = APIRouter()
 
+# /logs/histogram aggregates over the full logs table — expensive and
+# polled constantly by the UI. Cache only the unfiltered default call
+# (which is what the UI and locust hit); any filter bypasses.
+_HISTOGRAM_TTL = 5.0
+_DEFAULT_INTERVAL = 15
+_histogram_cache: tuple[Optional[list[dict[str, Any]]], float] = (None, 0.0)
+_histogram_lock: Optional[asyncio.Lock] = None
+
+
+def _reset_histogram_cache() -> None:
+    global _histogram_cache, _histogram_lock
+    _histogram_cache = (None, 0.0)
+    _histogram_lock = None
+
+
+async def _get_histogram_cached() -> list[dict[str, Any]]:
+    global _histogram_cache, _histogram_lock
+    value, ts = _histogram_cache
+    now = time.monotonic()
+    if value is not None and now - ts < _HISTOGRAM_TTL:
+        return value
+    if _histogram_lock is None:
+        _histogram_lock = asyncio.Lock()
+    async with _histogram_lock:
+        value, ts = _histogram_cache
+        now = time.monotonic()
+        if value is not None and now - ts < _HISTOGRAM_TTL:
+            return value
+        value = await repo.get_log_histogram(
+            search=None, start_time=None, end_time=None, interval_minutes=_DEFAULT_INTERVAL,
+        )
+        _histogram_cache = (value, time.monotonic())
+        return value
+
 
 @router.get("/logs/histogram", tags=["Logs"],
-    responses={401: {"description": "Could not validate credentials"}, 422: {"description": "Validation error"}},)
+    responses={401: {"description": "Could not validate credentials"}, 403: {"description": "Insufficient permissions"}, 422: {"description": "Validation error"}},)
+@_traced("api.get_logs_histogram")
 async def get_logs_histogram(
     search: Optional[str] = None,
     start_time: Optional[str] = Query(None),
     end_time: Optional[str] = Query(None),
     interval_minutes: int = Query(15, ge=1),
-    current_user: str = Depends(get_current_user)
+    user: dict = Depends(require_viewer)
 ) -> list[dict[str, Any]]:
     def _norm(v: Optional[str]) -> Optional[str]:
         if v in (None, "null", "NULL", "undefined", ""):
@@ -25,4 +63,6 @@ async def get_logs_histogram(
     st = _norm(start_time)
     et = _norm(end_time)
 
+    if s is None and st is None and et is None and interval_minutes == _DEFAULT_INTERVAL:
+        return await _get_histogram_cached()
     return await repo.get_log_histogram(search=s, start_time=st, end_time=et, interval_minutes=interval_minutes)