From b2366bf8a620286bfeb2a3e999198fd2f75371f1 Mon Sep 17 00:00:00 2001
From: Ankush Menat <ankush@frappe.io>
Date: Thu, 29 Jun 2023 15:03:57 +0530
Subject: [PATCH] fix: accurately handle socket close/loss event

---
 frappe/public/js/frappe/socketio_client.js |  9 -----
 socketio.js                                | 41 ++++++++++++++--------
 2 files changed, 27 insertions(+), 23 deletions(-)

diff --git a/frappe/public/js/frappe/socketio_client.js b/frappe/public/js/frappe/socketio_client.js
index 5c625a9346..9e70e6a835 100644
--- a/frappe/public/js/frappe/socketio_client.js
+++ b/frappe/public/js/frappe/socketio_client.js
@@ -91,17 +91,8 @@ class RealTimeClient {
 				return;
 			}
 
-			// me.doc_unsubscribe(frm.doctype, frm.docname);
 			me.doc_close(frm.doctype, frm.docname);
 		});
-
-		window.addEventListener("beforeunload", () => {
-			if (!cur_frm || !cur_frm.doc || cur_frm.is_new()) {
-				return;
-			}
-
-			me.doc_close(cur_frm.doctype, cur_frm.docname);
-		});
 	}
 
 	get_host(port = 3000) {
diff --git a/socketio.js b/socketio.js
index 285ccfd96a..e4570bcfce 100644
--- a/socketio.js
+++ b/socketio.js
@@ -42,6 +42,7 @@ io.use((socket, next) => {
 			socket.user = res.body.message.user;
 			socket.user_type = res.body.message.user_type;
 			socket.sid = cookies.sid;
+			socket.subscribed_documents = [];
 			next();
 		})
 		.catch((e) => {
@@ -93,14 +94,14 @@ io.on("connection", function (socket) {
 			doctype,
 			docname,
 			callback: () => {
-				var room = get_doc_room(socket, doctype, docname);
+				let room = get_doc_room(socket, doctype, docname);
 				socket.join(room);
 			},
 		});
 	});
 
 	socket.on("doc_unsubscribe", function (doctype, docname) {
-		var room = get_doc_room(socket, doctype, docname);
+		let room = get_doc_room(socket, doctype, docname);
 		socket.leave(room);
 	});
 
@@ -110,11 +111,12 @@ io.on("connection", function (socket) {
 			doctype,
 			docname,
 			callback: () => {
-				var room = get_open_doc_room(socket, doctype, docname);
+				let room = get_open_doc_room(socket, doctype, docname);
 				socket.join(room);
+				socket.subscribed_documents.push([doctype, docname]);
 
 				// show who is currently viewing the form
-				send_users({
+				notify_subscribed_doc_users({
 					socket: socket,
 					doctype: doctype,
 					docname: docname,
@@ -125,16 +127,17 @@ io.on("connection", function (socket) {
 
 	socket.on("doc_close", function (doctype, docname) {
 		// remove this user from the list of 'who is currently viewing the form'
-		var room = get_open_doc_room(socket, doctype, docname);
+		let room = get_open_doc_room(socket, doctype, docname);
 		socket.leave(room);
-		send_users(
-			{
-				socket: socket,
-				doctype: doctype,
-				docname: docname,
-			},
-			"view"
-		);
+		socket.subscribed_documents = socket.subscribed_documents.filter(([dt, dn]) => {
+			!(dt == doctype && dn == docname);
+		});
+
+		notify_subscribed_doc_users({
+			socket: socket,
+			doctype: doctype,
+			docname: docname,
+		});
 	});
 
 	socket.on("open_in_editor", (data) => {
@@ -267,7 +270,7 @@ function can_subscribe_doctype(args) {
 		});
 }
 
-function send_users(args) {
+function notify_subscribed_doc_users(args) {
 	if (!(args && args.doctype && args.docname)) {
 		return;
 	}
@@ -292,3 +295,13 @@ function send_users(args) {
 		users: Array.from(new Set(users)),
 	});
 }
+
+io.sockets.on("connection", function (socket) {
+	socket.on("disconnect", () => user_disconnected(socket));
+});
+
+function user_disconnected(socket) {
+	socket.subscribed_documents.forEach(([doctype, docname]) => {
+		notify_subscribed_doc_users({ socket, doctype, docname });
+	});
+}