From f390e8c5862e59cb618d0303506d54bef07f3a4a Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Sun, 21 Jun 2026 12:50:44 +0000
Subject: [PATCH] Fix Uptime Kuma listResources missing monitorList/heartbeat
 events
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Listeners for monitorList/importantHeartbeatList/heartbeat were being
attached after the login ack resolved, but the server pushes that
data right after login — sometimes in the same tick as the ack — so
Socket.IO dropped it before a listener existed. Listeners now attach
before login is sent.
---
 backend/src/integrations/uptimeKuma.ts | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/backend/src/integrations/uptimeKuma.ts b/backend/src/integrations/uptimeKuma.ts
index eaefe47..7130da9 100644
--- a/backend/src/integrations/uptimeKuma.ts
+++ b/backend/src/integrations/uptimeKuma.ts
@@ -23,9 +23,14 @@ function connectAndLogin(
   baseUrl: string,
   username: string,
   password: string,
+  onSocket?: (socket: Socket) => void,
 ): Promise<Socket> {
   return new Promise((resolve, reject) => {
     const socket = io(baseUrl, { transports: ['websocket', 'polling'], reconnection: false, timeout: 10000 })
+    // Attach event listeners before the login ack arrives — Uptime Kuma's
+    // server pushes monitorList/heartbeat right after login, sometimes in the
+    // same tick as the ack, and Socket.IO drops events with no listener yet.
+    onSocket?.(socket)
 
     const timer = setTimeout(() => {
       socket.disconnect()
@@ -74,22 +79,22 @@ export const uptimeKuma: IntegrationAdapter = {
     const password = secrets.password
     if (!baseUrl || !username || !password) return []
 
-    const socket = await connectAndLogin(baseUrl, username, password)
-    try {
-      const monitors = new Map<number, UptimeKumaMonitor>()
-      const lastHeartbeat = new Map<number, Heartbeat>()
+    const monitors = new Map<number, UptimeKumaMonitor>()
+    const lastHeartbeat = new Map<number, Heartbeat>()
 
-      socket.on('monitorList', (list: Record<string, UptimeKumaMonitor>) => {
+    const socket = await connectAndLogin(baseUrl, username, password, (s) => {
+      s.on('monitorList', (list: Record<string, UptimeKumaMonitor>) => {
         for (const m of Object.values(list)) monitors.set(m.id, m)
       })
-      socket.on('importantHeartbeatList', (monitorId: number, beats: Heartbeat[]) => {
+      s.on('importantHeartbeatList', (monitorId: number, beats: Heartbeat[]) => {
         const latest = beats[beats.length - 1]
         if (latest) lastHeartbeat.set(monitorId, latest)
       })
-      socket.on('heartbeat', (beat: Heartbeat & { monitorID: number }) => {
+      s.on('heartbeat', (beat: Heartbeat & { monitorID: number }) => {
         lastHeartbeat.set(beat.monitorID, beat)
       })
-
+    })
+    try {
       // Server pushes these events asynchronously right after login — there's no
       // single "done" signal, so give it a short window to arrive.
       await new Promise((resolve) => setTimeout(resolve, 2500))