network/websockets: extract heartbeat into a separate module

src/network/websockets/server/heartbeat.ts

@@ -0,0 +1,28 @@
+import type WebSocket from "ws";
+
+export function heartbeat(getClients: () => Set<WebSocket>) {
+ function setGood(this: any) {
+ this.lifeFlag = "good";
+ }
+ setInterval(function ping() {
+ getClients().forEach(
+ (socket: WebSocket & { lifeFlag?: "good" | "sleepy" }) => {
+ if (socket.lifeFlag === undefined) {
+ socket.lifeFlag = "good";
+ socket.on("pong", setGood);
+ socket.on("message", setGood);
+ return;
+ }
+ if (socket.lifeFlag === "good") {
+ socket.lifeFlag = "sleepy";
+ socket.ping();
+ return;
+ }
+ if (socket.lifeFlag === "sleepy") {
+ socket.terminate();
+ return;
+ }
+ }
+ );
+ }, 60000);
+}

src/network/websockets/server/index.ts

@@ -2,6 +2,7 @@ import { createNanoEvents } from "nanoevents";
 import WebSocket from "ws";
 import { jsonSerialization } from "../serialization";
 import { makeAuthQueue } from "./authQueue";
+import { heartbeat } from "./heartbeat";
 import { stringy, K, KV, Params, ValueContainer } from "./types";
 
 export function runWebsocketServer<AuthDetails>(params: Params<AuthDetails>) {
@@ -47,30 +48,8 @@ export function runWebsocketServer<AuthDetails>(params: Params<AuthDetails>) {
  server: params.server,
  });
 
- function heartbeat(this: any) {
- this.lifeFlag = "good";
- }
- setInterval(function ping() {
- server.clients.forEach(
- (socket: WebSocket & { lifeFlag?: "good" | "sleepy" }) => {
- if (socket.lifeFlag === undefined) {
- socket.lifeFlag = "good";
- socket.on("pong", heartbeat);
- socket.on("message", heartbeat);
- return;
- }
- if (socket.lifeFlag === "good") {
- socket.lifeFlag = "sleepy";
- socket.ping();
- return;
- }
- if (socket.lifeFlag === "sleepy") {
- socket.terminate();
- return;
- }
- }
- );
- }, 60000);
+ heartbeat(() => server.clients);
+
  server.on("connection", function (socket: WebSocket & { isAlive?: boolean }) {
  const authQueue = makeAuthQueue<AuthDetails>({
  onTerminate: () => socket.terminate(),