From 32b47921e5c48c2986b1d83f020504964765b878 Mon Sep 17 00:00:00 2001
From: Jeremy Zhang <jkzhang@uw.edu>
Date: Thu, 28 Jun 2018 08:05:08 +0000
Subject: [PATCH] Better reconnect logic. Refetch messages over http once
 reconnected when exceeded 1 min

---
 .../titanembeds/blueprints/gateway/gateway.py |  2 ++
 webapp/titanembeds/static/js/embed.js         | 21 +++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/webapp/titanembeds/blueprints/gateway/gateway.py b/webapp/titanembeds/blueprints/gateway/gateway.py
index 815ce78..5ccb465 100644
--- a/webapp/titanembeds/blueprints/gateway/gateway.py
+++ b/webapp/titanembeds/blueprints/gateway/gateway.py
@@ -86,6 +86,8 @@ class Gateway(Namespace):
                 emit("revoke")
                 time.sleep(1000)
                 disconnect()
+            else:
+                emit("ack")
         else:
             if not guild_accepts_visitors(guild_id):
                 disconnect()
diff --git a/webapp/titanembeds/static/js/embed.js b/webapp/titanembeds/static/js/embed.js
index 8a795f1..bc26356 100644
--- a/webapp/titanembeds/static/js/embed.js
+++ b/webapp/titanembeds/static/js/embed.js
@@ -37,6 +37,8 @@
     var current_user_discord_id; // Current user discord snowflake id, eg mine is 140252024666062848
     var visitor_mode = false; // Keep track of if using the visitor mode or authenticate mode
     var socket = null; // Socket.io object
+    var socket_last_ack = null; // Socket.io last acknowledgement Moment obj
+    var socket_error_should_refetch = false; // If true, the next ack will trigger a http refetch if socket connected
     var authenticated_users_list = []; // List of all authenticated users
     var unauthenticated_users_list = []; // List of all guest users
     var discord_users_list = []; // List of all discord users that are probably online
@@ -1255,6 +1257,7 @@
             }
         }
         fet.done(function(data) {
+            socket_error_should_refetch = false;
             var status = data.status;
             if (visitor_mode) {
                 update_embed_userchip(false, null, "Titan", null, "0001", null);
@@ -1929,6 +1932,13 @@
         socket.on("guest_icon_change", function (icon) {
             global_guest_icon = icon.guest_icon;
         });
+        
+        socket.on("ack", function () {
+            socket_last_ack = moment();
+            if (socket && socket_error_should_refetch) {
+                run_fetch_routine();
+            }
+        });
     }
     
     function update_socket_channels() {
@@ -1939,6 +1949,17 @@
     }
     
     function send_socket_heartbeat() {
+        if (socket_last_ack) {
+            var now = moment();
+            var duration = moment.duration(now.diff(socket_last_ack)).minutes();
+            if (socket && duration >= 1) { // server must hanged, lets reconnect
+                socket_error_should_refetch = true;
+                socket.disconnect();
+                socket = null;
+                initiate_websockets();
+            }
+        }
+        
         if (socket) {
             socket.emit("heartbeat", {"guild_id": guild_id, "visitor_mode": visitor_mode});
         }