Implement sync source-only mode in ServeSession and ChangeBatcher

- Added support for a new sync mode in ServeSession that filters property changes to only include the Source property when the server indicates it is in source-only mode.
- Updated ChangeBatcher to handle the new syncSourceOnly parameter, ensuring that only relevant property changes are processed based on the server's capabilities.
- Enhanced API response to include sync_source_only flag, indicating the server's sync capabilities.
- Adjusted related functions to accommodate the new sync logic, improving data synchronization efficiency.

plugin/src/App/init.lua

@@ -106,13 +106,17 @@ function App:init()
 			-- Our notif is now out of date- redoing will not restore the patch
 			-- since we've undone even further. Dismiss the notif.
 			cleanup()
-			dismissNotif()
+			if dismissNotif then
+				dismissNotif()
+			end
 		end)
 		redoConnection = ChangeHistoryService.OnRedo:Once(function(redoneAction: string)
 			if redoneAction == action then
 				-- The user has restored the patch, so we can dismiss the notif
 				cleanup()
-				dismissNotif()
+				if dismissNotif then
+					dismissNotif()
+				end
 			end
 		end)
 	end)

plugin/src/ChangeBatcher/createPatchSet.lua

@@ -12,7 +12,7 @@ local PatchSet = require(script.Parent.Parent.PatchSet)
 
 local encodePatchUpdate = require(script.Parent.encodePatchUpdate)
 
-return function(instanceMap, propertyChanges)
+return function(instanceMap, propertyChanges, syncSourceOnly)
 	local patch = PatchSet.newEmpty()
 
 	for instance, properties in propertyChanges do
@@ -30,8 +30,20 @@ return function(instanceMap, propertyChanges)
 				Log.warn("Cannot sync non-nil Parent property changes yet")
 			end
 		else
-			local update = encodePatchUpdate(instance, instanceId, properties)
+			if syncSourceOnly then
-			table.insert(patch.updated, update)
+				-- Filter to only Source property when server is in source-only mode
+				if properties.Source then
+					local update = encodePatchUpdate(instance, instanceId, { Source = true })
+					if update then
+						table.insert(patch.updated, update)
+					end
+				end
+			else
+				local update = encodePatchUpdate(instance, instanceId, properties)
+				if update then
+					table.insert(patch.updated, update)
+				end
+			end
 		end
 
 		propertyChanges[instance] = nil

plugin/src/ChangeBatcher/init.lua

@@ -27,11 +27,16 @@ function ChangeBatcher.new(instanceMap, onChangesFlushed)
 		__instanceMap = instanceMap,
 		__onChangesFlushed = onChangesFlushed,
 		__pendingPropertyChanges = {},
+		__syncSourceOnly = false,
 	}, ChangeBatcher)
 
 	return self
 end
 
+function ChangeBatcher:setSyncSourceOnly(enabled)
+	self.__syncSourceOnly = enabled
+end
+
 function ChangeBatcher:stop()
 	self.__renderSteppedConnection:Disconnect()
 	self.__pendingPropertyChanges = {}
@@ -69,7 +74,7 @@ function ChangeBatcher:__flush()
 		return nil
 	end
 
-	local patch = createPatchSet(self.__instanceMap, self.__pendingPropertyChanges)
+	local patch = createPatchSet(self.__instanceMap, self.__pendingPropertyChanges, self.__syncSourceOnly)
 
 	if PatchSet.isEmpty(patch) then
 		return nil

plugin/src/ServeSession.lua

@@ -100,6 +100,7 @@ function ServeSession.new(options)
 		__status = Status.NotStarted,
 		__apiContext = options.apiContext,
 		__twoWaySync = options.twoWaySync,
+		__syncSourceOnly = false,
 		__reconciler = reconciler,
 		__instanceMap = instanceMap,
 		__changeBatcher = changeBatcher,
@@ -196,6 +197,11 @@ function ServeSession:start()
 		:connect()
 		:andThen(function(serverInfo)
 			self:setLoadingText("Loading initial data from server...")
+
+			-- Configure sync mode based on server capabilities
+			self.__syncSourceOnly = serverInfo.syncSourceOnly or false
+			self.__changeBatcher:setSyncSourceOnly(self.__syncSourceOnly)
+
 			return self:__initialSync(serverInfo):andThen(function()
 				self:setLoadingText("Starting sync loop...")
 				self:__setStatus(Status.Connected, serverInfo.projectName)
@@ -526,8 +532,20 @@ function ServeSession:__initialSync(serverInfo)
 					continue
 				end
 
-				local update = encodePatchUpdate(instance, change.id, change.changedProperties)
+				local propertiesToSync = change.changedProperties
-				table.insert(inversePatch.updated, update)
+				if self.__syncSourceOnly then
+					-- Filter to only Source property when server is in source-only mode
+					if propertiesToSync.Source then
+						propertiesToSync = { Source = propertiesToSync.Source }
+					else
+						continue
+					end
+				end
+
+				local update = encodePatchUpdate(instance, change.id, propertiesToSync)
+				if update then
+					table.insert(inversePatch.updated, update)
+				end
 			end
 			-- Add the removed instances back to Rojo
 			-- selene:allow(empty_if, unused_variable, empty_loop)

src/web/api.rs

@@ -95,6 +95,7 @@ impl ApiService {
             place_id: self.serve_session.place_id(),
             game_id: self.serve_session.game_id(),
             root_instance_id,
+            sync_source_only: true,
         })
     }
 

src/web/interface.rs

@@ -165,6 +165,10 @@ pub struct ServerInfoResponse {
     pub game_id: Option<u64>,
     pub place_id: Option<u64>,
     pub root_instance_id: Ref,
+    /// When true, the server only supports syncing script Source property changes.
+    /// Other property changes will be ignored.
+    #[serde(default)]
+    pub sync_source_only: bool,
 }
 
 /// Response body from /api/read/{id}