From 52754e038a3d025cd22d9745127c1234b1eb8790 Mon Sep 17 00:00:00 2001
From: James Allen <james@sharelatex.com>
Date: Mon, 24 Oct 2016 16:36:40 +0100
Subject: [PATCH 1/2] Reconnect gracefully when asked to by real-time

---
 .../ide/connection/ConnectionManager.coffee   | 29 +++++++++++++++++--
 .../ide/references/ReferencesManager.coffee   |  7 ++++-
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/services/web/public/coffee/ide/connection/ConnectionManager.coffee b/services/web/public/coffee/ide/connection/ConnectionManager.coffee
index f3d14a3e3d..97530b8e4e 100644
--- a/services/web/public/coffee/ide/connection/ConnectionManager.coffee
+++ b/services/web/public/coffee/ide/connection/ConnectionManager.coffee
@@ -27,6 +27,7 @@ define [], () ->
 
 			@connected = false
 			@userIsInactive = false
+			@gracefullyReconnecting = false
 			
 			@$scope.connection = 
 				reconnecting: false
@@ -54,6 +55,7 @@ define [], () ->
 			@ide.socket.on "connect", () =>
 				sl_console.log "[socket.io connect] Connected"
 				@connected = true
+				@gracefullyReconnecting = false
 				@ide.pushEvent("connected")
 
 				@$scope.$apply () =>
@@ -81,7 +83,7 @@ define [], () ->
 				@$scope.$apply () =>
 					@$scope.connection.reconnecting = false
 
-				if !$scope.connection.forced_disconnect and !@userIsInactive
+				if !$scope.connection.forced_disconnect and !@userIsInactive and !@gracefullyReconnecting
 					@startAutoReconnectCountdown()
 
 			@ide.socket.on 'forceDisconnect', (message) =>
@@ -97,7 +99,11 @@ define [], () ->
 				setTimeout () ->
 					location.reload()
 				, 10 * 1000
-				
+			
+			@ide.socket.on "reconnectGracefully", () =>
+				sl_console.log "Reconnect gracefully"
+				@reconnectGracefully()
+
 		joinProject: () ->
 			sl_console.log "[joinProject] joining..."
 			@ide.socket.emit 'joinProject', {
@@ -180,3 +186,22 @@ define [], () ->
 				@$scope.$apply () =>
 					@$scope.connection.inactive_disconnect = true
 
+		RECONNECT_GRACEFULLY_RETRY_INTERVAL: 5000 # ms
+		MAX_RECONNECT_GRACEFULLY_INTERVAL: 60 * 5 * 1000 # 5 minutes
+		reconnectGracefully: () ->
+			@reconnectGracefullyStarted ?= new Date()
+			userIsInactive = (new Date() - @lastUserAction) > @RECONNECT_GRACEFULLY_RETRY_INTERVAL
+			maxIntervalReached = (new Date() - @reconnectGracefullyStarted) > @MAX_RECONNECT_GRACEFULLY_INTERVAL
+			if userIsInactive or maxIntervalReached
+				sl_console.log "[reconnectGracefully] User didn't do anything for last 5 seconds, reconnecting"
+				@_reconnectGracefullyNow()
+			else
+				sl_console.log "[reconnectGracefully] User is working, will try again in 5 seconds"
+				setTimeout () =>
+					@reconnectGracefully()
+				, @RECONNECT_GRACEFULLY_RETRY_INTERVAL
+		
+		_reconnectGracefullyNow: () ->
+			@gracefullyReconnecting = true
+			@reconnectGracefullyStarted = null
+			@reconnectImmediately()
\ No newline at end of file
diff --git a/services/web/public/coffee/ide/references/ReferencesManager.coffee b/services/web/public/coffee/ide/references/ReferencesManager.coffee
index 2f1e95c5b1..c5d7c2348b 100644
--- a/services/web/public/coffee/ide/references/ReferencesManager.coffee
+++ b/services/web/public/coffee/ide/references/ReferencesManager.coffee
@@ -17,8 +17,13 @@ define [
 			# When we join the project:
 			#   index all references files
 			#   and don't broadcast to all clients
+			@inited = false
 			@$scope.$on 'project:joined', (e) =>
-				@indexAllReferences(false)
+				# We only need to grab the references when the editor first loads,
+				# not on every reconnect
+				if !@inited
+					@inited = true
+					@indexAllReferences(false)
 
 			setTimeout(
 				(self) ->

From 43aeb5a21df2c4f975f05ef84d7904bbadf40be9 Mon Sep 17 00:00:00 2001
From: James Allen <james@sharelatex.com>
Date: Tue, 25 Oct 2016 14:09:36 +0100
Subject: [PATCH 2/2] Clear SERVERID cookie when reconnecting gracefully

---
 .../web/public/coffee/ide/connection/ConnectionManager.coffee   | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/services/web/public/coffee/ide/connection/ConnectionManager.coffee b/services/web/public/coffee/ide/connection/ConnectionManager.coffee
index 97530b8e4e..811587e5ad 100644
--- a/services/web/public/coffee/ide/connection/ConnectionManager.coffee
+++ b/services/web/public/coffee/ide/connection/ConnectionManager.coffee
@@ -204,4 +204,6 @@ define [], () ->
 		_reconnectGracefullyNow: () ->
 			@gracefullyReconnecting = true
 			@reconnectGracefullyStarted = null
+			# Clear cookie so we don't go to the same backend server
+			$.cookie("SERVERID", "", { expires: -1, path: "/" })
 			@reconnectImmediately()
\ No newline at end of file