From 32184330d92c9c92aa199e8b05f16a84cf98d8d1 Mon Sep 17 00:00:00 2001
From: Brian Gough <brian.gough@overleaf.com>
Date: Mon, 22 Mar 2021 11:15:59 +0000
Subject: [PATCH] delay closing by 1 minute for deployment flip

---
 services/real-time/app.js                      | 2 +-
 services/real-time/app/js/DeploymentManager.js | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/services/real-time/app.js b/services/real-time/app.js
index 832bf52a53..bde00b2e17 100644
--- a/services/real-time/app.js
+++ b/services/real-time/app.js
@@ -85,7 +85,7 @@ io.configure(function () {
 // a 200 response on '/' is required for load balancer health checks
 // these operate separately from kubernetes readiness checks
 app.get('/', function (req, res) {
-  if (Settings.serviceIsClosed || Settings.shutDownInProgress) {
+  if (Settings.shutDownInProgress || DeploymentManager.deploymentIsClosed()) {
     res.sendStatus(503) // Service unavailable
   } else {
     res.send('real-time is open')
diff --git a/services/real-time/app/js/DeploymentManager.js b/services/real-time/app/js/DeploymentManager.js
index a86db02dd1..a3201e6b21 100644
--- a/services/real-time/app/js/DeploymentManager.js
+++ b/services/real-time/app/js/DeploymentManager.js
@@ -9,10 +9,13 @@ const FILE_CHECK_INTERVAL = 5000
 const statusFile = settings.deploymentFile
 const deploymentColour = settings.deploymentColour
 
+var serviceCloseTime
+
 function updateDeploymentStatus(fileContent) {
   const closed = fileContent && fileContent.indexOf(deploymentColour) === -1
   if (closed && !settings.serviceIsClosed) {
     settings.serviceIsClosed = true
+    serviceCloseTime = Date.now() + 60 * 1000 // delay closing by 1 minute
     logger.warn({ fileContent }, 'closing service')
   } else if (!closed && settings.serviceIsClosed) {
     settings.serviceIsClosed = false
@@ -49,5 +52,8 @@ module.exports = {
       checkStatusFileSync() // perform an initial synchronous check at start up
       setInterval(pollStatusFile, FILE_CHECK_INTERVAL) // continue checking periodically
     }
+  },
+  deploymentIsClosed() {
+    return settings.serviceIsClosed && Date.now() > serviceCloseTime
   }
 }