From dc67eace2456e0e3c34083f3e38318ab26558ad0 Mon Sep 17 00:00:00 2001
From: Laurent Cozic <laurent@cozic.net>
Date: Mon, 29 Nov 2021 18:39:07 +0000
Subject: [PATCH] Server: Allow disabling NTP time drift check

---
 packages/server/src/app.ts | 10 ++++++----
 packages/server/src/env.ts |  4 ++--
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/packages/server/src/app.ts b/packages/server/src/app.ts
index 044680a2c..f0e091986 100644
--- a/packages/server/src/app.ts
+++ b/packages/server/src/app.ts
@@ -251,12 +251,14 @@ async function main() {
 
 		appLogger().info(`Starting server v${config().appVersion} (${env}) on port ${config().port} and PID ${process.pid}...`);
 
-		const timeDrift = await getDeviceTimeDrift();
-		if (Math.abs(timeDrift) > config().maxTimeDrift) {
-			throw new Error(`The device time drift is ${timeDrift}ms (Max allowed: ${config().maxTimeDrift}ms) - cannot continue as it could cause data loss and conflicts on the sync clients. You may increase env var MAX_TIME_DRIFT to pass the check.`);
+		if (config().maxTimeDrift) {
+			const timeDrift = await getDeviceTimeDrift();
+			if (Math.abs(timeDrift) > config().maxTimeDrift) {
+				throw new Error(`The device time drift is ${timeDrift}ms (Max allowed: ${config().maxTimeDrift}ms) - cannot continue as it could cause data loss and conflicts on the sync clients. You may increase env var MAX_TIME_DRIFT to pass the check.`);
+			}
+			appLogger().info(`NTP time offset: ${timeDrift}ms`);
 		}
 
-		appLogger().info(`NTP time offset: ${timeDrift}ms`);
 		appLogger().info('Running in Docker:', runningInDocker());
 		appLogger().info('Public base URL:', config().baseUrl);
 		appLogger().info('API base URL:', config().apiBaseUrl);
diff --git a/packages/server/src/env.ts b/packages/server/src/env.ts
index 2076391cc..d00135d81 100644
--- a/packages/server/src/env.ts
+++ b/packages/server/src/env.ts
@@ -21,8 +21,8 @@ const defaultEnvValues: EnvVariables = {
 	// milliseconds is normally not an issue unless many clients are modifying
 	// the same note at the exact same time. But past a certain limit, it might
 	// mean the server clock is incorrect and should be fixed, as that could
-	// result in clients generating many conflicts.
-	// https://github.com/laurent22/joplin/issues/5738
+	// result in clients generating many conflicts. Set to 0 to disable the
+	// check. https://github.com/laurent22/joplin/issues/5738
 
 	MAX_TIME_DRIFT: 100,