Add websocket keepalive

quartz/cli/handlers.js

@@ -317,14 +317,10 @@ export async function handleBuild(argv) {
   }
 
   if (argv.serve) {
-    const connections = []
-    const clientRefresh = () => connections.forEach((conn) => conn.send("rebuild"))
-
     if (argv.baseDir !== "" && !argv.baseDir.startsWith("/")) {
       argv.baseDir = "/" + argv.baseDir
     }
 
-    await build(clientRefresh)
     const server = http.createServer(async (req, res) => {
       if (argv.baseDir && !req.url?.startsWith(argv.baseDir)) {
         console.log(
@@ -410,8 +406,28 @@ export async function handleBuild(argv) {
       return serve()
     })
     server.listen(argv.port)
+    function heartbeat() {
+      this.isAlive = true
+    }
     const wss = new WebSocketServer({ port: argv.wsPort })
-    wss.on("connection", (ws) => connections.push(ws))
+    wss.on("connection", function connection(ws) {
+      ws.isAlive = true
+      ws.on("error", console.error)
+      ws.on("pong", heartbeat)
+    })
+    const interval = setInterval(function ping() {
+      wss.clients.forEach(function each(ws) {
+        if (ws.isAlive === false) return ws.terminate()
+
+        ws.isAlive = false
+        ws.ping()
+      })
+    }, 30000)
+    wss.on("close", function close() {
+      clearInterval(interval)
+    })
+    const clientRefresh = () => wss.clients.forEach((conn) => conn.send("rebuild"))
+    await build(clientRefresh)
     console.log(
       chalk.cyan(
         `Started a Quartz server listening at http://localhost:${argv.port}${argv.baseDir}`,