Clean up "actionCreator" and part of typing-status expiry

src/events/doEventActionSideEffects.js

@@ -4,11 +4,12 @@
 import { AppState } from 'react-native';
 import type { GlobalState, GetState, Dispatch, Message } from '../types';
 import type { EventAction } from '../actionTypes';
-import { EVENT_NEW_MESSAGE } from '../actionConstants';
+import { EVENT_NEW_MESSAGE, EVENT_TYPING_START } from '../actionConstants';
 import { isHomeNarrow, isMessageInNarrow } from '../utils/narrow';
 import { getActiveAccount, getChatScreenParams, getOwnEmail } from '../selectors';
 import { playMessageSound } from '../utils/sound';
 import { NULL_ARRAY } from '../nullObjects';
+import { ensureTypingStatusExpiryLoop } from '../typing/typingActions';
 
 /**
  * React to incoming `MessageEvent`s.
@@ -43,7 +44,7 @@ const messageEvent = (state: GlobalState, message: Message): void => {
 /**
  * React to actions dispatched for Zulip server events.
  *
- * To be dispatched after the event actions are dispatched.
+ * To be dispatched before the event actions are dispatched.
  */
 export default (action: EventAction) => async (dispatch: Dispatch, getState: GetState) => {
   const state = getState();
@@ -52,6 +53,9 @@ export default (action: EventAction) => async (dispatch: Dispatch, getState: Get
       messageEvent(state, action.message);
       break;
     }
+    case EVENT_TYPING_START:
+      dispatch(ensureTypingStatusExpiryLoop());
+      break;
     default:
   }
 };

src/events/eventActions.js

@@ -9,7 +9,6 @@ import { deadQueue } from '../session/sessionActions';
 import eventToAction from './eventToAction';
 import doEventActionSideEffects from './doEventActionSideEffects';
 import { tryGetAuth } from '../selectors';
-import actionCreator from '../actionCreator';
 import { BackoffMachine } from '../utils/async';
 import { ApiError } from '../api/apiErrors';
 
@@ -73,16 +72,15 @@ export const startEventPolling = (queueId: number, eventId: number) => async (
 
       const actions = eventsToActions(getState(), events);
 
-      actionCreator(dispatch, actions, getState());
-      dispatchOrBatch(dispatch, actions);
-
       actions.forEach(action => {
         // These side effects should not be moved to reducers, which
         // are explicitly not the place for side effects (see
         // https://redux.js.org/faq/actions).
         dispatch(doEventActionSideEffects(action));
       });
 
+      dispatchOrBatch(dispatch, actions);
+
       lastEventId = Math.max.apply(null, [lastEventId, ...events.map(x => x.id)]);
     } catch (e) {
       if (e.httpStatus === 401) {

src/typing/typingActions.js

@@ -1,7 +1,41 @@
 /* @flow strict-local */
-import type { Action } from '../types';
+import type { Action, Dispatch, GetState } from '../types';
+
+import { sleep } from '../utils/async';
+import { getTyping } from '../directSelectors';
 
 export const clearTyping = (outdatedNotifications: string[]): Action => ({
   type: 'CLEAR_TYPING',
   outdatedNotifications,
 });
+
+const typingStatusExpiryLoop = () => async (dispatch: Dispatch, getState: GetState) => {
+  // loop to auto dismiss typing notifications after typingNotificationTimeout
+  // eslint-disable-next-line no-constant-condition
+  while (true) {
+    await sleep(15000);
+    const currentTime = new Date().getTime();
+    const typing = getTyping(getState());
+    if (Object.keys(typing).length === 0) {
+      break; // break if no typing notifications
+    }
+    const outdatedNotifications = [];
+    Object.keys(typing).forEach(recipients => {
+      if (currentTime - typing[recipients].time >= 15000) {
+        outdatedNotifications.push(recipients);
+      }
+    });
+    dispatch(clearTyping(outdatedNotifications));
+  }
+};
+
+/** Start the typing-status expiry loop, if there isn't one already. */
+export const ensureTypingStatusExpiryLoop = () => async (
+  dispatch: Dispatch,
+  getState: GetState,
+) => {
+  const state = getState();
+  if (Object.keys(state.typing).length === 0) {
+    dispatch(typingStatusExpiryLoop());
+  }
+};