From 5b54d36b375e82488e63eadee35512fe683c4fd5 Mon Sep 17 00:00:00 2001
From: Brian Gough <brian.gough@overleaf.com>
Date: Tue, 13 Aug 2019 10:41:35 +0100
Subject: [PATCH 1/4] fail readiness check when shutting down

---
 services/real-time/app.coffee | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/services/real-time/app.coffee b/services/real-time/app.coffee
index 7b53730ce6..56db154f83 100644
--- a/services/real-time/app.coffee
+++ b/services/real-time/app.coffee
@@ -56,7 +56,10 @@ app.get "/", (req, res, next) ->
 	res.send "real-time-sharelatex is alive"
 
 app.get "/status", (req, res, next) ->
-	res.send "real-time-sharelatex is alive"
+	if shutDownInProgress
+		res.send 503 # Service unavailable
+	else
+		res.send "real-time-sharelatex is alive"
 
 app.get "/debug/events", (req, res, next) ->
 	Settings.debugEvents = parseInt(req.query?.count,10) || 20

From 53431953fcd55ba064216d0fb98f93564ebec32a Mon Sep 17 00:00:00 2001
From: Brian Gough <brian.gough@overleaf.com>
Date: Tue, 13 Aug 2019 16:56:48 +0100
Subject: [PATCH 2/4] make shutDownInProgress available via settings

---
 services/real-time/app.coffee | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/services/real-time/app.coffee b/services/real-time/app.coffee
index 56db154f83..5a78588591 100644
--- a/services/real-time/app.coffee
+++ b/services/real-time/app.coffee
@@ -56,7 +56,7 @@ app.get "/", (req, res, next) ->
 	res.send "real-time-sharelatex is alive"
 
 app.get "/status", (req, res, next) ->
-	if shutDownInProgress
+	if Settings.shutDownInProgress
 		res.send 503 # Service unavailable
 	else
 		res.send "real-time-sharelatex is alive"
@@ -120,17 +120,17 @@ forceDrain = ->
 		DrainManager.startDrain(io, 4)
 	, Settings.forceDrainMsDelay
 
-shutDownInProgress = false
+Settings.shutDownInProgress = false
 if Settings.forceDrainMsDelay?
 	Settings.forceDrainMsDelay = parseInt(Settings.forceDrainMsDelay, 10)
 	logger.log forceDrainMsDelay: Settings.forceDrainMsDelay,"forceDrainMsDelay enabled"
 	for signal in ['SIGINT', 'SIGHUP', 'SIGQUIT', 'SIGUSR1', 'SIGUSR2', 'SIGTERM', 'SIGABRT']
 		process.on signal, ->
-			if shutDownInProgress
+			if Settings.shutDownInProgress
 				logger.log signal: signal, "shutdown already in progress, ignoring signal"
 				return
 			else
-				shutDownInProgress = true
+				Settings.shutDownInProgress = true
 				logger.log signal: signal, "received interrupt, cleaning up"
 				shutdownCleanly(signal)
 				forceDrain()

From 0708f717fd48e1745eac8420543fd8501ab9f6a5 Mon Sep 17 00:00:00 2001
From: Brian Gough <brian.gough@overleaf.com>
Date: Tue, 13 Aug 2019 16:59:15 +0100
Subject: [PATCH 3/4] reject connections when shutdown in progress

send a message to the client to reconnect immediately
---
 services/real-time/app/coffee/Router.coffee | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/services/real-time/app/coffee/Router.coffee b/services/real-time/app/coffee/Router.coffee
index ad74ebffa1..838d8de6f5 100644
--- a/services/real-time/app/coffee/Router.coffee
+++ b/services/real-time/app/coffee/Router.coffee
@@ -39,6 +39,11 @@ module.exports = Router =
 		app.post "/drain", httpAuth, HttpApiController.startDrain
 
 		session.on 'connection', (error, client, session) ->
+			if settings.shutDownInProgress
+				client.emit("connectionRejected", {message: "retry"})
+				client.disconnect()
+				return
+
 			if client? and error?.message?.match(/could not look up session by key/)
 				logger.warn err: error, client: client?, session: session?, "invalid session"
 				# tell the client to reauthenticate if it has an invalid session key

From 20d442120f1727626c50d7d56c62ce79f6fd8fc7 Mon Sep 17 00:00:00 2001
From: Brian Gough <brian.gough@overleaf.com>
Date: Tue, 13 Aug 2019 17:36:53 +0100
Subject: [PATCH 4/4] notify docupdate if the flush is from a shutdown

---
 services/real-time/app/coffee/DocumentUpdaterManager.coffee | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/services/real-time/app/coffee/DocumentUpdaterManager.coffee b/services/real-time/app/coffee/DocumentUpdaterManager.coffee
index 40ef992d8f..9968b78753 100644
--- a/services/real-time/app/coffee/DocumentUpdaterManager.coffee
+++ b/services/real-time/app/coffee/DocumentUpdaterManager.coffee
@@ -40,7 +40,8 @@ module.exports = DocumentUpdaterManager =
 		logger.log project_id:project_id, "deleting project from document updater"
 		timer = new metrics.Timer("delete.mongo.project")
 		# flush the project in the background when all users have left
-		url = "#{settings.apis.documentupdater.url}/project/#{project_id}?background=true"
+		url = "#{settings.apis.documentupdater.url}/project/#{project_id}?background=true" +
+			(if settings.shutDownInProgress then "&shutdown=true" else "")
 		request.del url, (err, res, body)->
 			timer.done()
 			if err?