From 2b0515dc55f2be7b0d88afa9257f852c823a9b40 Mon Sep 17 00:00:00 2001
From: Maxim Devaev <mdevaev@gmail.com>
Date: Mon, 24 Jul 2023 16:25:25 +0300
Subject: [PATCH] cached /export/prometheus/metrics

---
 PKGBUILD                     | 1 +
 kvmd/apps/kvmd/api/export.py | 8 +++++++-
 testenv/Dockerfile           | 1 +
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/PKGBUILD b/PKGBUILD
index 46057aed..2684b167 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -44,6 +44,7 @@ depends=(
 	python-yaml
 	python-aiohttp
 	python-aiofiles
+	python-async-lru
 	python-passlib
 	python-pyotp
 	python-qrcode
diff --git a/kvmd/apps/kvmd/api/export.py b/kvmd/apps/kvmd/api/export.py
index cfcbde41..a5d4d0bf 100644
--- a/kvmd/apps/kvmd/api/export.py
+++ b/kvmd/apps/kvmd/api/export.py
@@ -24,6 +24,8 @@ import asyncio
 
 from typing import Any
 
+import async_lru
+
 from aiohttp.web import Request
 from aiohttp.web import Response
 
@@ -49,6 +51,10 @@ class ExportApi:
 
     @exposed_http("GET", "/export/prometheus/metrics")
     async def __prometheus_metrics_handler(self, _: Request) -> Response:
+        return Response(text=(await self.__get_prometheus_metrics()))
+
+    @async_lru.alru_cache(maxsize=1, ttl=5)
+    async def __get_prometheus_metrics(self) -> str:
         (atx_state, hw_state, fan_state, gpio_state) = await asyncio.gather(*[
             self.__atx.get_state(),
             self.__info_manager.get_submanager("hw").get_state(),
@@ -68,7 +74,7 @@ class ExportApi:
         self.__append_prometheus_rows(rows, hw_state["health"], "pikvm_hw")
         self.__append_prometheus_rows(rows, fan_state, "pikvm_fan")
 
-        return Response(text="\n".join(rows))
+        return "\n".join(rows)
 
     def __append_prometheus_rows(self, rows: list[str], value: Any, path: str) -> None:
         if isinstance(value, bool):
diff --git a/testenv/Dockerfile b/testenv/Dockerfile
index 7dedc9ec..a4246989 100644
--- a/testenv/Dockerfile
+++ b/testenv/Dockerfile
@@ -41,6 +41,7 @@ RUN pacman --noconfirm --ask=4 -Syy \
 		python-yaml \
 		python-aiohttp \
 		python-aiofiles \
+		python-async-lru \
 		python-periphery \
 		python-passlib \
 		python-pyotp \