From 9a851d6ccebcab6ab6a7d6cccc4134f93a07f427 Mon Sep 17 00:00:00 2001
From: Henry Oswald <henry.oswald@sharelatex.com>
Date: Tue, 4 Dec 2018 13:47:04 +0000
Subject: [PATCH] mvp for safe shutdown

---
 services/real-time/app.coffee | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/services/real-time/app.coffee b/services/real-time/app.coffee
index 0857fcc835..034dc2d915 100644
--- a/services/real-time/app.coffee
+++ b/services/real-time/app.coffee
@@ -78,3 +78,20 @@ server.listen port, host, (error) ->
 
 # Stop huge stack traces in logs from all the socket.io parsing steps.
 Error.stackTraceLimit = 10
+
+
+shutdownCleanly = (signal) ->
+	return () ->
+		logger.log signal: signal, "received interrupt, cleaning up"
+		connectedClients = io.sockets.clients()?.length
+		logger.log {connectedClients, signal}, "looking to shut down process"
+		if connectedClients == 0
+			logger.log("no clients connected, exiting")
+			process.exit()
+		else
+			setTimeout () ->
+				shutdownCleanly(signal)
+			, 10000
+
+for signal in ['SIGINT', 'SIGHUP', 'SIGQUIT', 'SIGUSR1', 'SIGUSR2', 'SIGTERM', 'SIGABRT']
+	process.on signal, shutdownCleanly(signal)