refactor(user-status): improve useHeartbeat

- Add notes
- Simplify
- Wait for heartbeat request before waiting for the next heartbeat
- Also restart on going to away

Signed-off-by: Grigorii K. Shartsev <me@shgk.me>

Author: ShGKme

src/talk/renderer/TitleBar/TitleBar.vue

@@ -11,11 +11,11 @@ import { appData } from '../../../app/AppData.js'
 import { BUILD_CONFIG } from '../../../shared/build.config.ts'
 import { useDevMode } from '../../../shared/useDevMode.ts'
 import { useAppConfigStore } from '../Settings/appConfig.store.ts'
-import { useUserStatusHeartbeat } from '../UserStatus/useHeartbeat.ts'
+import { useHeartbeat } from '../UserStatus/useHeartbeat.ts'
 import { useUserStatusStore } from '../UserStatus/userStatus.store.ts'
 
 useUserStatusStore()
-useUserStatusHeartbeat()
+useHeartbeat()
 useAppConfigStore()
 
 const channel = __CHANNEL__

src/talk/renderer/UserStatus/useHeartbeat.ts

@@ -1,51 +1,71 @@
-/**
+/*
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
 
+import { createSharedComposable } from '@vueuse/core'
 import { onBeforeUnmount, watch } from 'vue'
 import { useAppIdle } from './composables/useAppIdle.ts'
 import { useUserStatusStore } from './userStatus.store.ts'
 
-/** How often to update the user status */
-const USER_STATUS_UPDATE_INTERVAL = 5 * 60 * 1000 // 5 minutes
+// General notes:
+// - Server has INVALIDATE_STATUS_THRESHOLD with 15 minutes, preventing immediate status update on heartbeat request
+//   See: https://github.com/nextcloud/server/blob/v31.0.5/apps/user_status/lib/Service/StatusService.php
+// - However, "away" status has higher priority than "online"
+//   See: https://github.com/nextcloud/server/blob/v31.0.5/apps/user_status/lib/Service/StatusService.php#L41-L48
+// - Thus:
+//   - Changing "Away -> Online" has a 15 minutes threshold
+//   - Changing "Online -> Away" is immediate
+// - See: https://github.com/nextcloud/server/blob/master/apps/user_status/lib/Listener/UserLiveStatusListener.php#L75-L87
+// - This might change in future to have symmetric behavior on heartbeat
+
+/** How often to send the heartbeat. Must be less than 15 min. */
+const HEARTBEAT_INTERVAL = 5 * 60 * 1000 // 5 minutes
 
-/** How long user is considered active */
-const USER_STATUS_ACTIVE_TIMEOUT = 2 * 60 * 1000 // 2 minutes
+/** How long user is considered active before going away */
+const AWAY_THRESHOLD = 2 * 60 * 1000 // 2 minutes
 
 /**
- * Composable to update the user status in the background
+ * Background heartbeat with user status update
  */
-export function useUserStatusHeartbeat() {
+export const useHeartbeat = createSharedComposable(() => {
 	const userStatusStore = useUserStatusStore()
-	const isIdle = useAppIdle(USER_STATUS_ACTIVE_TIMEOUT)
+	const isAway = useAppIdle(AWAY_THRESHOLD)
+
+	let heartbeatTimeout: number | undefined
 
 	/**
 	 * Send a heartbeat
 	 */
-	function heartbeat() {
-		userStatusStore.updateUserStatusWithHeartbeat(isIdle.value)
+	async function heartbeat() {
+		try {
+			await userStatusStore.updateUserStatusWithHeartbeat(isAway.value)
+		} catch (error) {
+			console.error('Error on heartbeat:', error)
+		}
 	}
 
-	let heartbeatInterval: number | undefined
-	const restartHeartbeat = () => {
-		if (heartbeatInterval) {
-			clearInterval(heartbeatInterval)
+	/**
+	 * Start heartbeat interval
+	 */
+	async function restartHeartbeat() {
+		if (heartbeatTimeout) {
+			clearTimeout(heartbeatTimeout)
 		}
-		heartbeat()
+		await heartbeat()
 		// TODO: fix when main and renderer process have separate tsconfig
-		heartbeatInterval = setInterval(heartbeat, USER_STATUS_UPDATE_INTERVAL) as unknown as number
+		heartbeatTimeout = setTimeout(heartbeat, HEARTBEAT_INTERVAL) as unknown as number
 	}
 
-	watch(isIdle, () => {
-		if (!isIdle.value) {
-			restartHeartbeat()
-		}
+	// Restart heartbeat to immediately notify server on state change
+	watch(isAway, () => {
+		// Note: both app and system level activity state changes to inactive with a threshold.
+		// Only lock/unlock state can be changed many times in a short period, but it is unlikely
+		// Thus it unlikely overloads with heartbeat, no need to debounce
+		restartHeartbeat()
 	}, { immediate: true })
 
 	onBeforeUnmount(() => {
-		clearInterval(heartbeatInterval)
+		clearTimeout(heartbeatTimeout)
 	})
-
-	return { isIdle }
-}
+})