feat: add debounce to health indicator (#2594)

package-lock.json

@@ -7536,9 +7536,17 @@
       "version": "4.17.18",
       "resolved": "https://registry.npmjs.org/@types/lodash/-/lodash-4.17.18.tgz",
       "integrity": "sha512-KJ65INaxqxmU6EoCiJmRPZC9H9RVWCRd349tXM2M3O5NA7cY6YL7c0bHAHQ93NOfTObEQ004kd2QVHs/r0+m4g==",
-      "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/lodash.debounce": {
+      "version": "4.0.9",
+      "resolved": "https://registry.npmjs.org/@types/lodash.debounce/-/lodash.debounce-4.0.9.tgz",
+      "integrity": "sha512-Ma5JcgTREwpLRwMM+XwBR7DaWe96nC38uCBDFKZWbNKD+osjVzdpnUSwBcqCptrp16sSOLBAUb50Car5I0TCsQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@types/lodash": "*"
+      }
+    },
     "node_modules/@types/markdown-it": {
       "version": "14.1.2",
       "resolved": "https://registry.npmjs.org/@types/markdown-it/-/markdown-it-14.1.2.tgz",
@@ -37608,12 +37616,14 @@
         "@libp2p/ping": "2.0.35",
         "@libp2p/websockets": "9.2.16",
         "@noble/hashes": "^1.3.3",
+        "@types/lodash.debounce": "^4.0.9",
         "@waku/core": "0.0.38",
         "@waku/discovery": "0.0.11",
         "@waku/interfaces": "0.0.33",
         "@waku/proto": "^0.0.13",
         "@waku/utils": "0.0.26",
-        "libp2p": "2.8.11"
+        "libp2p": "2.8.11",
+        "lodash.debounce": "^4.0.8"
       },
       "devDependencies": {
         "@libp2p/interface": "2.10.4",

packages/sdk/package.json

@@ -67,20 +67,22 @@
     "@libp2p/ping": "2.0.35",
     "@libp2p/websockets": "9.2.16",
     "@noble/hashes": "^1.3.3",
+    "@types/lodash.debounce": "^4.0.9",
     "@waku/core": "0.0.38",
     "@waku/discovery": "0.0.11",
     "@waku/interfaces": "0.0.33",
     "@waku/proto": "^0.0.13",
     "@waku/utils": "0.0.26",
-    "libp2p": "2.8.11"
+    "libp2p": "2.8.11",
+    "lodash.debounce": "^4.0.8"
   },
   "devDependencies": {
     "@libp2p/interface": "2.10.4",
-    "@types/chai": "^4.3.11",
     "@rollup/plugin-commonjs": "^25.0.7",
     "@rollup/plugin-json": "^6.0.0",
     "@rollup/plugin-node-resolve": "^15.2.3",
     "@rollup/plugin-replace": "^5.0.5",
+    "@types/chai": "^4.3.11",
     "@types/mocha": "^10.0.9",
     "@waku/build-utils": "*",
     "chai": "^5.1.1",
@@ -104,4 +106,4 @@
     "LICENSE",
     "README.md"
   ]
-}
+}

packages/sdk/src/health_indicator/health_indicator.ts

@@ -7,6 +7,7 @@ import {
   WakuEvent
 } from "@waku/interfaces";
 import { Logger } from "@waku/utils";
+import debounce from "lodash.debounce";
 
 type PeerEvent<T> = (_event: CustomEvent<T>) => void;
 
@@ -24,10 +25,13 @@ interface IHealthIndicator {
 }
 
 export class HealthIndicator implements IHealthIndicator {
+  private isStarted = false;
+
   private readonly libp2p: Libp2p;
   private readonly events: IWakuEventEmitter;
 
   private value: HealthStatus = HealthStatus.Unhealthy;
+  private readonly debouncedAssessHealth: ReturnType<typeof debounce>;
 
   public constructor(params: HealthIndicatorParams) {
     this.libp2p = params.libp2p;
@@ -35,9 +39,18 @@ export class HealthIndicator implements IHealthIndicator {
 
     this.onPeerIdentify = this.onPeerIdentify.bind(this);
     this.onPeerDisconnected = this.onPeerDisconnected.bind(this);
+
+    this.debouncedAssessHealth = debounce(() => {
+      void this.assessHealth();
+    }, 100);
   }
 
   public start(): void {
+    if (this.isStarted) {
+      return;
+    }
+
+    this.isStarted = true;
     log.info("start: adding listeners to libp2p");
 
     this.libp2p.addEventListener(
@@ -49,10 +62,15 @@ export class HealthIndicator implements IHealthIndicator {
       this.onPeerDisconnected as PeerEvent<PeerId>
     );
 
-    void this.assessHealth();
+    this.debouncedAssessHealth();
   }
 
   public stop(): void {
+    if (!this.isStarted) {
+      return;
+    }
+
+    this.isStarted = false;
     log.info("stop: removing listeners to libp2p");
 
     this.libp2p.removeEventListener(
@@ -63,22 +81,22 @@ export class HealthIndicator implements IHealthIndicator {
       "peer:disconnect",
       this.onPeerDisconnected as PeerEvent<PeerId>
     );
+
+    this.debouncedAssessHealth.cancel();
   }
 
   public toValue(): HealthStatus {
     return this.value;
   }
 
-  private async onPeerDisconnected(_event: CustomEvent<PeerId>): Promise<void> {
+  private onPeerDisconnected(_event: CustomEvent<PeerId>): void {
     log.info(`onPeerDisconnected: received libp2p event`);
-    await this.assessHealth();
+    this.debouncedAssessHealth();
   }
 
-  private async onPeerIdentify(
-    _event: CustomEvent<IdentifyResult>
-  ): Promise<void> {
+  private onPeerIdentify(_event: CustomEvent<IdentifyResult>): void {
     log.info(`onPeerIdentify: received libp2p event`);
-    await this.assessHealth();
+    this.debouncedAssessHealth();
   }
 
   private async assessHealth(): Promise<void> {