From 86b5281e8624d309d60d9a63f6d2bd0b35b6aecc Mon Sep 17 00:00:00 2001
From: Charlie Lamb <charlielamb20@icloud.com>
Date: Wed, 22 Apr 2026 10:38:09 +0100
Subject: [PATCH] chore: no flakely errors on redis

---
 server/src/utils/cacheUtils/cacheUtils.ts   | 15 ++++++++++++---
 server/tests/unit/cache/cache-utils.test.ts | 12 ++++++++++++
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/server/src/utils/cacheUtils/cacheUtils.ts b/server/src/utils/cacheUtils/cacheUtils.ts
index a69401e46..e036381a9 100644
--- a/server/src/utils/cacheUtils/cacheUtils.ts
+++ b/server/src/utils/cacheUtils/cacheUtils.ts
@@ -14,6 +14,12 @@ const markDefaultRedisAvailability = (targetRedis: Redis, available: boolean) =>
 	available ? markRedisCommandSuccess() : markRedisCommandFailure();
 };
 
+const isRedisAvailabilityError = (targetRedis: Redis, error: unknown) => {
+	if (targetRedis.status !== "ready") return true;
+	const message = error instanceof Error ? error.message : String(error);
+	return /ECONN|ETIMEDOUT|timeout|closed|writeable|max retries/i.test(message);
+};
+
 const warnRedisUnavailable = ({
 	source,
 	error,
@@ -68,7 +74,8 @@ export const tryRedisNx = async <TUnavailable, TSuccess, TExists>({
 		if (result === "OK") return await onSuccess();
 		return await onKeyAlreadyExists();
 	} catch (error) {
-		markDefaultRedisAvailability(targetRedis, false);
+		if (isRedisAvailabilityError(targetRedis, error))
+			markDefaultRedisAvailability(targetRedis, false);
 		warnRedisUnavailable({ source: "tryRedisNx:error", error });
 		return await onRedisUnavailable();
 	}
@@ -103,7 +110,8 @@ export const tryRedisWrite = async <T>(
 			? true
 			: T | null;
 	} catch (error) {
-		markDefaultRedisAvailability(targetRedis, false);
+		if (isRedisAvailabilityError(targetRedis, error))
+			markDefaultRedisAvailability(targetRedis, false);
 		warnRedisUnavailable({ source: "tryRedisWrite:error", error });
 		return null as T extends void ? true : T | null;
 	}
@@ -134,7 +142,8 @@ export const tryRedisRead = async <T>(
 		markDefaultRedisAvailability(targetRedis, true);
 		return result;
 	} catch (error) {
-		markDefaultRedisAvailability(targetRedis, false);
+		if (isRedisAvailabilityError(targetRedis, error))
+			markDefaultRedisAvailability(targetRedis, false);
 		warnRedisUnavailable({ source: "tryRedisRead:error", error });
 		return null;
 	}
diff --git a/server/tests/unit/cache/cache-utils.test.ts b/server/tests/unit/cache/cache-utils.test.ts
index e39273836..e49d4d23d 100644
--- a/server/tests/unit/cache/cache-utils.test.ts
+++ b/server/tests/unit/cache/cache-utils.test.ts
@@ -139,4 +139,16 @@ describe("cache utils", () => {
 
 		expect(getRedisAvailability().state).toBe("healthy");
 	});
+
+	test("Redis command errors do not mark Redis unavailable", async () => {
+		markRedisCommandSuccess();
+		markRedisCommandSuccess();
+		expect(getRedisAvailability().state).toBe("healthy");
+
+		await tryRedisWrite(async () => {
+			throw new Error("ERR user_script:2: unexpected symbol near '#'");
+		});
+
+		expect(getRedisAvailability().state).toBe("healthy");
+	});
 });