Add setting to disable oplog for cache sync

packages/rocketchat-i18n/i18n/en.i18n.json

@@ -522,6 +522,8 @@
   "Food_and_Drink": "Food & Drink",
   "Footer": "Footer",
   "For_your_security_you_must_enter_your_current_password_to_continue": "For your security, you must enter your current password to continue",
+  "Force_Disable_OpLog_For_Cache": "Force disable OpLog for Cache",
+  "Force_Disable_OpLog_For_Cache_Description": "Will not use OpLog to sync cache even when it's available",
   "Force_SSL": "Force SSL",
   "Force_SSL_Description": "*Caution!* _Force SSL_ should never be used with reverse proxy. If you have a reverse proxy, you should do the redirect THERE. This option exists for deployments like Heroku, that does not allow the redirect configuration at the reverse proxy.",
   "Forgot_password": "Forgot your password",
@@ -1516,4 +1518,4 @@
   "your_message_optional": "your message (optional)",
   "Your_password_is_wrong": "Your password is wrong!",
   "Your_push_was_sent_to_s_devices": "Your push was sent to %s devices"
-}
\ No newline at end of file
+}

packages/rocketchat-lib/server/models/_BaseDb.js

@@ -29,7 +29,7 @@ class ModelsBaseDb extends EventEmitter {
 
 		this.wrapModel();
 
-		this.isOplogAvailable = MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle && !!MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle.onOplogEntry;
+		this.isOplogAvailable = MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle && !!MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle.onOplogEntry && RocketChat.settings.get('Force_Disable_OpLog_For_Cache') === false;
 
 		// When someone start listening for changes we start oplog if available
 		this.once('newListener', (event/*, listener*/) => {
@@ -130,6 +130,10 @@ class ModelsBaseDb extends EventEmitter {
 	}
 
 	processOplogRecord(action) {
+		if (this.isOplogAvailable === false) {
+			return;
+		}
+
 		if (action.op.op === 'i') {
 			this.emit('change', {
 				action: 'insert',

packages/rocketchat-lib/server/startup/settings.coffee

@@ -99,6 +99,7 @@ RocketChat.settings.addGroup 'General', ->
 	@add 'Force_SSL', false, { type: 'boolean', public: true }
 	@add 'GoogleTagManager_id', '', { type: 'string', public: true }
 	@add 'Bugsnag_api_key', '', { type: 'string', public: false }
+	@add 'Force_Disable_OpLog_For_Cache', false, { type: 'boolean', public: false }
 	@add 'Restart', 'restart_server', { type: 'action', actionText: 'Restart_the_server' }
 
 	@section 'UTF8', ->

server/startup/serverRunning.coffee

 Meteor.startup ->
-	isOplogState = 'Enabled'
-	if not MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle?
-		isOplogState = 'Disabled'
+	oplogState = 'Disabled'
+	if MongoInternals.defaultRemoteCollectionDriver().mongo._oplogHandle?.onOplogEntry?
+		oplogState = 'Enabled'
+		if RocketChat.settings.get('Force_Disable_OpLog_For_Cache') is true
+			oplogState += ' (Disabled for Cache Sync)'
 
 	Meteor.setTimeout ->
 		msg = [
 			"     Version: #{RocketChat.Info.version}"
 			"Process Port: #{process.env.PORT}"
 			"    Site URL: #{RocketChat.settings.get('Site_Url')}"
-			"       OpLog: #{isOplogState}"
+			"       OpLog: #{oplogState}"
 		].join('\n')
 
 		SystemLogger.startup_box msg, 'SERVER RUNNING'