From a95fdbbf102863d9f31d101ed6f904cafee53179 Mon Sep 17 00:00:00 2001
From: Ian Gulliver <ian@flamingcow.tv>
Date: Wed, 25 Nov 2020 23:34:09 +0000
Subject: [PATCH] Real heartbeat timeouts server -> client

---
 main.go          |  3 +--
 static/remote.js | 10 ++++++++++
 static/remote.ts | 15 +++++++++++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/main.go b/main.go
index a3cb1eb..bfd3e0e 100644
--- a/main.go
+++ b/main.go
@@ -623,8 +623,7 @@ func writeInitial(client *client, w http.ResponseWriter, flusher http.Flusher) {
 }
 
 func writeHeartbeat(w http.ResponseWriter, flusher http.Flusher) {
-	fmt.Fprintf(w, ":\n\n")
-	flusher.Flush()
+	writeEvent(&event{}, w, flusher)
 }
 
 func writeEvent(e *event, w http.ResponseWriter, flusher http.Flusher) {
diff --git a/static/remote.js b/static/remote.js
index 64a47c5..7ef87da 100644
--- a/static/remote.js
+++ b/static/remote.js
@@ -74,7 +74,15 @@ function watch(roomId, clientId, adminSecret, prnt) {
 }
 function createEventSource(url) {
     const es = new EventSource(url.toString());
+    let lastMessage = performance.now();
+    const intId = setInterval(() => {
+        if (performance.now() - lastMessage > 10000) {
+            console.warn("timeout");
+            es.dispatchEvent(new Event("error"));
+        }
+    }, 1000);
     es.addEventListener("open", () => {
+        console.info("connected");
         messageBus.dispatchEvent(new Event("open"));
     });
     es.addEventListener("message", (e) => {
@@ -82,10 +90,12 @@ function createEventSource(url) {
             data: e.data,
             lastEventId: e.lastEventId,
         }));
+        lastMessage = performance.now();
     });
     es.addEventListener("error", () => {
         console.warn("disconnected");
         es.close();
+        clearInterval(intId);
         setTimeout(() => createEventSource(url), 3000);
         messageBus.dispatchEvent(new Event("error"));
     });
diff --git a/static/remote.ts b/static/remote.ts
index 9a70763..2800ec8 100644
--- a/static/remote.ts
+++ b/static/remote.ts
@@ -159,7 +159,17 @@ function watch(roomId: string, clientId: string, adminSecret: string | null, prn
 function createEventSource(url: URL) {
 	const es = new EventSource(url.toString());
 
+	let lastMessage = performance.now();
+
+	const intId = setInterval(() => {
+		if (performance.now() - lastMessage > 10000) {
+			console.warn("timeout");
+			es.dispatchEvent(new Event("error"));
+		}
+	}, 1000);
+
 	es.addEventListener("open", () => {
+		console.info("connected");
 		messageBus.dispatchEvent(new Event("open"));
 	});
 
@@ -168,11 +178,16 @@ function createEventSource(url: URL) {
 			data: e.data,
 			lastEventId: e.lastEventId,
 		}));
+
+		lastMessage = performance.now();
 	});
 
 	es.addEventListener("error", () => {
 		console.warn("disconnected");
+
 		es.close();
+		clearInterval(intId);
+
 		setTimeout(() => createEventSource(url), 3000);
 
 		messageBus.dispatchEvent(new Event("error"));