Feat: new queueReleaseThrottle optional param for createNetworkMiddle…

…ware

README.md

@@ -269,7 +269,8 @@ createNetworkMiddleware(config: MiddlewareConfig): ReduxMiddleware
 
 type MiddlewareConfig = {
   regexActionType?: RegExp = /FETCH.*REQUEST/,
-  actionTypes?: Array<string> = []
+  actionTypes?: Array<string> = [],
+  queueReleaseThrottle?: number = 50,
 }
 ```
 
@@ -281,6 +282,8 @@ By default it's configured to intercept actions for fetching data following the
 
 `actionTypes`: array with additional action types to intercept that don't fulfil the RegExp criteria. For instance, it's useful for actions that carry along refreshing data, such as `REFRESH_LIST`.
 
+`queueReleaseThrottle`: waiting time in ms between dispatches when flushing the offline queue. Useful to reduce the server pressure when coming back online. Defaults to 50ms.
+
 ##### Thunks Config
 For `redux-thunk` library, the async flow is wrapped inside functions that will be lazily evaluated when dispatched, so our store is able to dispatch functions as well. Therefore, the configuration differs:
 
@@ -316,7 +319,9 @@ import { createNetworkMiddleware } from 'react-native-offline';
 import createSagaMiddleware from 'redux-saga';
 
 const sagaMiddleware = createSagaMiddleware();
-const networkMiddleware = createNetworkMiddleware();
+const networkMiddleware = createNetworkMiddleware({
+  queueReleaseThrottle: 200,
+});
 
 const store = createStore(
   rootReducer,

example/components/ConnectionToggler.js

@@ -6,7 +6,7 @@ function ConnectionToggler() {
   return (
     <DummyNetworkContext.Consumer>
       {({ toggleConnection }) => (
-        <View style={{ marginBottom: 30 }}>
+        <View style={{ marginBottom: 20 }}>
           <Button
             onPress={toggleConnection}
             title="Toggle Internet connection"

example/components/OfflineQueue.js

@@ -2,10 +2,10 @@ import React from 'react';
 import { View, StyleSheet, Text, ScrollView } from 'react-native';
 import { connect } from 'react-redux';
 
-function OfflineQueue({ queue }) {
+function OfflineQueue({ queue, title }) {
   return (
     <View style={{ height: 90, marginVertical: 8 }}>
-      <Text style={styles.title}>Offline Queue (FIFO)</Text>
+      <Text style={styles.title}>{title}</Text>
       <ScrollView
         style={{ flex: 1 }}
         contentContainerStyle={styles.queue}

example/package.json

@@ -15,7 +15,7 @@
     "expo": "^32.0.0",
     "react": "16.5.0",
     "react-native": "https://github.com/expo/react-native/archive/sdk-32.0.0.tar.gz",
-    "react-native-offline": "^4.2.0",
+    "react-native-offline": "4.3.0",
     "react-navigation": "^3.0.9",
     "redux": "^4.0.1",
     "redux-saga": "0.16.2"

example/redux/createStore.js

@@ -7,10 +7,14 @@ import createSagaMiddleware from 'redux-saga';
 import counter from './reducer';
 import rootSaga from './sagas';
 
-export default function createReduxStore({ withSaga = false } = {}) {
+export default function createReduxStore({
+  withSaga = false,
+  queueReleaseThrottle = 1000,
+} = {}) {
   const networkMiddleware = createNetworkMiddleware({
     regexActionType: /^OTHER/,
     actionTypes: ['ADD_ONE', 'SUB_ONE'],
+    queueReleaseThrottle,
   });
 
   const sagaMiddleware = createSagaMiddleware();

example/screens/ReduxScreen.js

@@ -1,5 +1,5 @@
 import React from 'react';
-import { Platform, View, StyleSheet, Image } from 'react-native';
+import { Platform, View, StyleSheet, Image, Text } from "react-native";
 import { ReduxNetworkProvider } from 'react-native-offline';
 import { Provider } from 'react-redux';
 
@@ -11,7 +11,7 @@ import Counter from '../components/Counter';
 import OfflineQueue from '../components/OfflineQueue';
 import ActionButtons from '../components/ActionButtons';
 
-const store = createStore();
+const store = createStore({ queueReleaseThrottle: 1000 });
 
 export default class ReduxScreen extends React.Component {
   static navigationOptions = {
@@ -42,7 +42,7 @@ export default class ReduxScreen extends React.Component {
                 <View style={styles.secondSection}>
                   <ActionButtons />
                   <View style={styles.offlineQueue}>
-                    <OfflineQueue />
+                    <OfflineQueue title="Offline Queue (FIFO), throttle = 1s" />
                   </View>
                 </View>
               </View>

example/screens/SagasScreen.js

@@ -7,7 +7,7 @@ import ActionButtons from '../components/ActionButtons';
 import OfflineQueue from '../components/OfflineQueue';
 import createStore from '../redux/createStore';
 
-const store = createStore({ withSaga: true });
+const store = createStore({ withSaga: true, queueReleaseThrottle: 250 });
 
 export default class SettingsScreen extends React.Component {
   static navigationOptions = {
@@ -42,7 +42,7 @@ export default class SettingsScreen extends React.Component {
           <View style={styles.secondSection}>
             <ActionButtons />
             <View style={styles.offlineQueue}>
-              <OfflineQueue />
+              <OfflineQueue title="Offline Queue (FIFO), throttle = 250ms" />
             </View>
           </View>
         </View>

example/yarn.lock

@@ -5592,10 +5592,10 @@ react-native-maps@expo/react-native-maps#v0.22.1-exp.0:
   version "0.22.1"
   resolved "https://codeload.github.com/expo/react-native-maps/tar.gz/e6f98ff7272e5d0a7fe974a41f28593af2d77bb2"
 
-react-native-offline@^4.2.0:
-  version "4.2.0"
-  resolved "https://registry.yarnpkg.com/react-native-offline/-/react-native-offline-4.2.0.tgz#baf2337a8126b93e1b9241c6b328bbe1c26a19c0"
-  integrity sha512-gFEs5oDEcSeUybnGQ/MlOI3Q9K8rH+cXcMWbyAoLDYnY8K6MCRXwOwfhFuTfKaRrcfMsywjTLcYetfNMMVN1ng==
+react-native-offline@4.3.0:
+  version "4.3.0"
+  resolved "https://registry.yarnpkg.com/react-native-offline/-/react-native-offline-4.3.0.tgz#6877e4a4b961e230e0a198bce2d0611ca8af9d89"
+  integrity sha512-hM+rNGHKpmagseFuhnok/c7uCrMqs70fHRzaqGBCKnTsio6ff3/wb7jomsuRjsR1Iy+DwBws+VUovcfpQAtuBQ==
   dependencies:
     lodash "^4.17.11"
     react-redux "^6.0.0"

package.json

@@ -1,6 +1,6 @@
 {
   "name": "react-native-offline",
-  "version": "4.2.0",
+  "version": "4.3.0",
   "description": "Handy toolbelt to deal with offline mode in React Native applications. Cross-platform, provides a smooth redux integration.",
   "main": "./src/index.js",
   "author": "Raul Gomez Acuña <[email protected]> (https://github.com/rgommezz)",
@@ -71,7 +71,7 @@
   "dependencies": {
     "lodash": "^4.17.11",
     "react-redux": "^6.0.0",
-    "redux":"4.x",
+    "redux": "4.x",
     "redux-saga": "^0.16.2"
   },
   "jest": {

src/components/ReduxNetworkProvider.js

@@ -13,7 +13,6 @@ import {
 type Props = {
   dispatch: FluxAction => FluxAction,
   isConnected: boolean,
-  actionQueue: Array<FluxAction>,
   pingTimeout?: number,
   pingServerUrl?: string,
   shouldPing?: boolean,
@@ -36,17 +35,10 @@ class ReduxNetworkProvider extends React.Component<Props> {
   };
 
   handleConnectivityChange = (isConnected: boolean) => {
-    const { isConnected: wasConnected, actionQueue, dispatch } = this.props;
-
+    const { isConnected: wasConnected, dispatch } = this.props;
     if (isConnected !== wasConnected) {
       dispatch(connectionChange(isConnected));
     }
-    // dispatching queued actions in order of arrival (if we have any)
-    if (!wasConnected && isConnected && actionQueue.length > 0) {
-      actionQueue.forEach((action: *) => {
-        dispatch(action);
-      });
-    }
   };
 
   render() {
@@ -65,7 +57,6 @@ class ReduxNetworkProvider extends React.Component<Props> {
 function mapStateToProps(state: { network: NetworkState }) {
   return {
     isConnected: state.network.isConnected,
-    actionQueue: state.network.actionQueue,
   };
 }
 

src/redux/createNetworkMiddleware.js

@@ -6,8 +6,9 @@ import {
   removeActionFromQueue,
   dismissActionsFromQueue,
 } from './actionCreators';
-import getSimilarActionInQueue from '../utils/getSimilarActionInQueue';
 import type { NetworkState } from '../types';
+import networkActionTypes from './actionTypes';
+import wait from '../utils/wait';
 
 type MiddlewareAPI<S> = {
   dispatch: (action: any) => void,
@@ -21,59 +22,114 @@ type State = {
 type Arguments = {|
   regexActionType: RegExp,
   actionTypes: Array<string>,
+  queueReleaseThrottle: number,
 |};
 
+function validateParams(regexActionType, actionTypes) {
+  if ({}.toString.call(regexActionType) !== '[object RegExp]')
+    throw new Error('You should pass a regex as regexActionType param');
+
+  if ({}.toString.call(actionTypes) !== '[object Array]')
+    throw new Error('You should pass an array as actionTypes param');
+}
+
+function findActionToBeDismissed(action, actionQueue) {
+  return find(actionQueue, (a: *) => {
+    const actionsToDismiss = get(a, 'meta.dismiss', []);
+    return actionsToDismiss.includes(action.type);
+  });
+}
+
+function isObjectAndShouldBeIntercepted(action, regexActionType, actionTypes) {
+  return (
+    typeof action === 'object' &&
+    (regexActionType.test(action.type) || actionTypes.includes(action.type))
+  );
+}
+
+function isThunkAndShouldBeIntercepted(action) {
+  return typeof action === 'function' && action.interceptInOffline === true;
+}
+
+function checkIfActionShouldBeIntercepted(
+  action,
+  regexActionType,
+  actionTypes,
+) {
+  return (
+    isObjectAndShouldBeIntercepted(action, regexActionType, actionTypes) ||
+    isThunkAndShouldBeIntercepted(action)
+  );
+}
+
+function didComeBackOnline(action, wasConnected) {
+  return (
+    action.type === networkActionTypes.CONNECTION_CHANGE &&
+    !wasConnected &&
+    action.payload === true
+  );
+}
+
+export const createReleaseQueue = (getState, next, delay) => async queue => {
+  // eslint-disable-next-line
+  for (const action of queue) {
+    const { isConnected } = getState().network;
+    if (isConnected) {
+      next(removeActionFromQueue(action));
+      next(action);
+      // eslint-disable-next-line
+      await wait(delay);
+    } else {
+      break;
+    }
+  }
+};
+
 function createNetworkMiddleware({
   regexActionType = /FETCH.*REQUEST/,
   actionTypes = [],
+  queueReleaseThrottle = 50,
 }: Arguments = {}) {
   return ({ getState }: MiddlewareAPI<State>) => (
     next: (action: any) => void,
   ) => (action: any) => {
-    if ({}.toString.call(regexActionType) !== '[object RegExp]')
-      throw new Error('You should pass a regex as regexActionType param');
+    const { isConnected, actionQueue } = getState().network;
+    const releaseQueue = createReleaseQueue(
+      getState,
+      next,
+      queueReleaseThrottle,
+    );
+    validateParams(regexActionType, actionTypes);
 
-    if ({}.toString.call(actionTypes) !== '[object Array]')
-      throw new Error('You should pass an array as actionTypes param');
+    const shouldInterceptAction = checkIfActionShouldBeIntercepted(
+      action,
+      regexActionType,
+      actionTypes,
+    );
 
-    const { isConnected, actionQueue } = getState().network;
+    if (shouldInterceptAction && isConnected === false) {
+      // Offline, preventing the original action from being dispatched.
+      // Dispatching an internal action instead.
+      return next(fetchOfflineMode(action));
+    }
 
-    const isObjectAndMatchCondition =
-      typeof action === 'object' &&
-      (regexActionType.test(action.type) || actionTypes.includes(action.type));
-
-    const isFunctionAndMatchCondition =
-      typeof action === 'function' && action.interceptInOffline === true;
-
-    if (isObjectAndMatchCondition || isFunctionAndMatchCondition) {
-      if (isConnected === false) {
-        // Offline, preventing the original action from being dispatched.
-        // Dispatching an internal action instead.
-        return next(fetchOfflineMode(action));
-      }
-      const actionQueued =
-        actionQueue.length > 0
-          ? getSimilarActionInQueue(action, actionQueue)
-          : null;
-      if (actionQueued) {
-        // Back online and the action that was queued is about to be dispatched.
-        // Removing action from queue, prior to handing over to next middleware or final dispatch
-        next(removeActionFromQueue(action));
-
-        return next(action);
-      }
+    const isBackOnline = didComeBackOnline(action, isConnected);
+    if (isBackOnline) {
+      // Dispatching queued actions in order of arrival (if we have any)
+      next(action);
+      return releaseQueue(actionQueue);
     }
 
-    // We don't want to dispatch actions all the time, but rather when there is a dismissal case
-    const isAnyActionToBeDismissed = find(actionQueue, (a: *) => {
-      const actionsToDismiss = get(a, 'meta.dismiss', []);
-      return actionsToDismiss.includes(action.type);
-    });
+    // Checking if we have a dismissal case
+    const isAnyActionToBeDismissed = findActionToBeDismissed(
+      action,
+      actionQueue,
+    );
     if (isAnyActionToBeDismissed && !isConnected) {
       next(dismissActionsFromQueue(action.type));
-      return next(action);
     }
 
+    // Proxy the original action to the next middleware on the chain or final dispatch
     return next(action);
   };
 }

src/redux/sagas.js

@@ -208,16 +208,10 @@ export function* checkInternetAccessSaga({
 export function* handleConnectivityChange(
   hasInternetAccess: boolean,
 ): Generator<*, *, *> {
-  const { actionQueue, isConnected } = yield select(networkSelector);
+  const { isConnected } = yield select(networkSelector);
   if (isConnected !== hasInternetAccess) {
     yield put(connectionChange(hasInternetAccess));
   }
-  if (hasInternetAccess && actionQueue.length > 0) {
-    // eslint-disable-next-line
-    for (const action of actionQueue) {
-      yield put(action);
-    }
-  }
 }
 
 /**

src/utils/wait.js

@@ -0,0 +1,2 @@
+const wait = t => new Promise(resolve => setTimeout(resolve, t));
+export default wait;