feat: add multiplayer feature flag (#6888)

* updated feature flag to type

* added feature flag dependency for pointer sharing and editor listing features

app/client/src/entities/FeatureFlag.ts

@@ -1,6 +1,7 @@
 type FeatureFlag = {
   COMMENT: boolean;
   JS_EDITOR: boolean;
+  MULTIPLAYER: boolean;
   LINTING: boolean;
   SNIPPET: boolean;
 };

app/client/src/pages/Editor/Canvas.tsx

@@ -1,5 +1,5 @@
 import React, { memo, useCallback } from "react";
-import store from "store";
+import store, { useSelector } from "store";
 import WidgetFactory from "utils/WidgetFactory";
 import { RenderModes } from "constants/WidgetConstants";
 import { ContainerWidgetProps } from "widgets/ContainerWidget";
@@ -17,6 +17,7 @@ import {
   APP_COLLAB_EVENTS,
   NAMESPACE_COLLAB_PAGE_EDIT,
 } from "constants/AppCollabConstants";
+import { isMultiplayerEnabledForUser as isMultiplayerEnabledForUserSelector } from "selectors/appCollabSelectors";
 
 interface CanvasProps {
   dsl: ContainerWidgetProps<WidgetProps>;
@@ -46,12 +47,16 @@ const shareMousePointer = (e: any, pageId: string) => {
 // TODO(abhinav): get the render mode from context
 const Canvas = memo((props: CanvasProps) => {
   const { pageId } = props;
+  const isMultiplayerEnabledForUser = useSelector(
+    isMultiplayerEnabledForUserSelector,
+  );
   const delayedShareMousePointer = useCallback(
     throttle((e) => shareMousePointer(e, pageId), 50, {
       trailing: false,
     }),
     [shareMousePointer, pageId],
   );
+
   try {
     return (
       <>
@@ -62,16 +67,19 @@ const Canvas = memo((props: CanvasProps) => {
           id="art-board"
           onMouseMove={(e) => {
             e.persist();
+            if (!isMultiplayerEnabledForUser) return;
             delayedShareMousePointer(e);
           }}
           width={props.dsl.rightColumn}
         >
           {props.dsl.widgetId &&
             WidgetFactory.createWidget(props.dsl, RenderModes.CANVAS)}
-          <CanvasMultiPointerArena
-            pageEditSocket={pageEditSocket}
-            pageId={pageId}
-          />
+          {isMultiplayerEnabledForUser && (
+            <CanvasMultiPointerArena
+              pageEditSocket={pageEditSocket}
+              pageId={pageId}
+            />
+          )}
         </ArtBoard>
       </>
     );

app/client/src/pages/Editor/EditorHeader.tsx

@@ -57,6 +57,7 @@ import { useLocation } from "react-router";
 import { setIsGitSyncModalOpen } from "actions/gitSyncActions";
 import RealtimeAppEditors from "./RealtimeAppEditors";
 import { EditorSaveIndicator } from "./EditorSaveIndicator";
+import { isMultiplayerEnabledForUser as isMultiplayerEnabledForUserSelector } from "selectors/appCollabSelectors";
 
 const HeaderWrapper = styled(StyledHeader)`
   width: 100%;
@@ -227,6 +228,10 @@ export function EditorHeader(props: EditorHeaderProps) {
     dispatch(setIsGitSyncModalOpen(true));
   }, [dispatch, setIsGitSyncModalOpen]);
 
+  const isMultiplayerEnabledForUser = useSelector(
+    isMultiplayerEnabledForUserSelector,
+  );
+
   return (
     <ThemeProvider theme={props.darkTheme}>
       <HeaderWrapper>
@@ -276,7 +281,9 @@ export function EditorHeader(props: EditorHeaderProps) {
         </HeaderSection>
         <HeaderSection>
           <EditorSaveIndicator />
-          <RealtimeAppEditors applicationId={applicationId} />
+          {isMultiplayerEnabledForUser && (
+            <RealtimeAppEditors applicationId={applicationId} />
+          )}
           <Boxed step={OnboardingStep.FINISH}>
             <FormDialogComponent
               Form={AppInviteUsersForm}

app/client/src/sagas/WebsocketSagas/WebsocketSagas.ts

@@ -1,6 +1,14 @@
 import { io } from "socket.io-client";
 import { eventChannel } from "redux-saga";
-import { fork, take, call, cancel, put, delay } from "redux-saga/effects";
+import {
+  fork,
+  take,
+  call,
+  cancel,
+  put,
+  delay,
+  select,
+} from "redux-saga/effects";
 import {
   ReduxActionTypes,
   ReduxSagaChannels,
@@ -17,6 +25,8 @@ import {
 } from "actions/websocketActions";
 
 import handleSocketEvent from "./handleSocketEvent";
+import { isMultiplayerEnabledForUser } from "selectors/appCollabSelectors";
+import { areCommentsEnabledForUserAndApp } from "selectors/commentsSelectors";
 
 function connect() {
   const socket = io();
@@ -85,6 +95,10 @@ function* handleIO(socket: any) {
 
 function* flow() {
   while (true) {
+    yield take([
+      ReduxActionTypes.FETCH_FEATURE_FLAGS_SUCCESS,
+      ReduxActionTypes.RETRY_WEBSOCKET_CONNECTION, // for manually triggering reconnection
+    ]);
     try {
       /**
        * Incase the socket is disconnected due to network latencies
@@ -93,13 +107,17 @@ function* flow() {
        * We only need to retry incase the socket connection isn't made
        * in the first attempt itself
        */
-      const socket = yield call(connect);
-      const task = yield fork(handleIO, socket);
-      yield put(setIsWebsocketConnected(true));
-      yield take([ReduxActionTypes.LOGOUT_USER_INIT]);
-      yield take();
-      yield cancel(task);
-      socket.disconnect();
+      const commentsEnabled = yield select(areCommentsEnabledForUserAndApp);
+      const multiplayerEnabled = yield select(isMultiplayerEnabledForUser);
+      if (commentsEnabled || multiplayerEnabled) {
+        const socket = yield call(connect);
+        const task = yield fork(handleIO, socket);
+        yield put(setIsWebsocketConnected(true));
+        yield take([ReduxActionTypes.LOGOUT_USER_INIT]);
+        yield take();
+        yield cancel(task);
+        socket.disconnect();
+      }
     } catch (e) {
       // this has to be non blocking
       yield fork(function*() {

app/client/src/selectors/appCollabSelectors.tsx

@@ -2,6 +2,7 @@ import { createSelector } from "reselect";
 import { AppState } from "reducers";
 import { AppCollabReducerState } from "reducers/uiReducers/appCollabReducer";
 import { getCurrentUser } from "./usersSelectors";
+import getFeatureFlags from "../utils/featureFlags";
 
 export const getAppCollabState = (state: AppState) => state.ui.appCollab;
 
@@ -11,3 +12,5 @@ export const getRealtimeAppEditors = createSelector(
   (appCollab: AppCollabReducerState, currentUser) =>
     appCollab.editors.filter((el) => el.email !== currentUser?.email),
 );
+
+export const isMultiplayerEnabledForUser = () => getFeatureFlags().MULTIPLAYER;