47
votes

I am using redux with connect and redux-thunk middleware and containers.

Currently when an user perform an action, example one click on a button, I need to dispatch that action (sync) which will dispatch other few actions (asynch).

I am aware dispatching actions from within the reducer is an anti pattern.

I would like to know what is a suitable place for this code.

Currently I am not sure if it should stay in:

  • The action creator.
  • In the container using store.subscribe.
8
I believe this describes the exact pattern you're looking for. Just read that page, the part you're most interested in is probably where they describe the fetchPosts function.Saad
@saadq thanks for your link, it looks like in the action creator... correct?Radex
Bear in mind that dispatch is a SYNCHRONOUS operation :)Ematipico

8 Answers

46
votes

The recommended way as per the documentation is in the action creator, like so:

function actionCreator(payload) {
    return dispatch => {
        dispatch(action1(payload))
        dispatch(action2(payload))
    }
}

Then you would probably want to attach the action creators as prop and pass it down to the container using mapDispatchToProps like in the example mentioned here. So it would look something like so:

const mapDispatchToProps = dispatch => ({
   action1: some_payload => dispatch(action1(some_payload))
   action2: some_payload => dispatch(action2(some_payload))
})

// your component
export default connect(mapStateToProps, mapDispatchToProps)(YourApp)

20
votes

As other pointed out The action creator is the right place for dispatching multiple actions.

Below an example of how action1 could dispatch other actions in your action creator.

const action1 = id => {
  return dispatch => {
    dispatch(action2(id))
    dispatch(action3(id))
  }
}
14
votes

The action creator is the correct location for dispatching multiple actions. Although code like the following would work:

function actionCreator(payload) {
    return dispatch => {
        dispatch(action1(payload))
        dispatch(action2(payload))
    }
}

I would highly recommend redux-thunk based action creators to always return a resolved Promise, so that such action creators can be part of another async call. So, the simplest update to the above would be:

function actionCreator(payload) {
    return dispatch => {
        dispatch(action1(payload));
        dispatch(action2(payload));
        return Promise.resolve();
    }
}

It would then be possible to dispatch to the above with: actionCreator(payload).then(doAnotherAction(anotherPayload)) or the following, if we need to maintain order of calls: actionCreator(payload).then(() => doAnotherAction(anotherPayload))

If you wish to 'future-proof' your action creator, so that it could handle calling both async and sync action creators, you could write it as:

function actionCreator(payload) {
    return dispatch =>
        Promise.resolve(dispatch(action1(payload))).then(
        () => dispatch(action2(payload)));
}

And, if you like ES6 arrow notation the above can be defined as:

const actionCreator = payload => dispatch =>
        Promise.resolve(dispatch(action1(payload))).then(
        () => dispatch(action2(payload)));
3
votes

While solution by @GibboK did not work for me:

const mapDispatchToProps = (dispatch) => ({
  action2: id => dispatch(Actions.action2(id)),
  action3: id => dispatch(Actions.action3(id)),
  action1: (dateId, attrId) => {
    return dispatch => {
      dispatch(Actions.action2(dateId));
      dispatch(Actions.action3(attrId));
    }
  }
});

I eventually went with redux-batched-actions. Worked like charm:

const mapDispatchToProps = (dispatch) => ({
  action2: id => dispatch(Actions.action2(id)),
  action3: id => dispatch(Actions.action3(id)),
  action1: (dateId, attrId) =>
    dispatch(batchActions([
      Actions.action2(dateId),
      Actions.action3(attrId)
    ]))
});
2
votes

If you have a Promise Middleware, you can use this syntax so you're able to use .then() on your dispatch(topLevelAction()):

export const topLevelAction = () => dispatch => {
    return Promise.all([dispatch(action1()), dispatch(action2()), dispatch(action3())])
}
0
votes

For guys in 2020... The actions are Supposed to be made in the action Creater. For those who would like to dispatch an action and fetch/post some data from the API can use this Idea.

lets assume we have an actions.js file and we want to dispatch a loading action before fetch data.

function requestPosts() {
    return {
      type: "loading"
    }
  }

This is the fetching action function

function fetchPosts() {
 return dispatch => {
    // dispatch the loading
    dispatch(requestPosts());
    // fetch data from api
  return fetch("https://www.yoururl.com/api")
   .then(response => response.json())
   .then(json => dispatch({
       type: "fetching successful",
       payload: json
    }));
  }
}
0
votes
"had similar issue. had to create a function 
that accepts object with  the actions you want to 
dispatch to the store and individual params for 
respective action"

dispatchMultiple({params: {
    params1: "<arg for first action>" ,
    params2: "<arg for second action>",
                        },

})
const dispatchMultiple = (obj) => {
    dispatch(obj.actions.action1(obj.params.params1));
    dispatch(obj.actions.action2(obj.params.params2));
  }; 
-2
votes

The easiest way is to use a specialized middleware redux-soldier:

import { createStore, applyMiddleware } from 'redux'
import { reduxSoldierMiddleware } from 'redux-soldier'

const store = createStore(rootReducer, applyMiddleware(reduxSoldierMiddleware))
store.dispatch([
  {type: 'INCREMENT'}, // traditional action
  addTodo('Start using redux-soldier'), // action creator
  fetchUser(), // thunk action
])

redux-soldier is also a full replacement for redux-thunk

For more info check the documentation redux-soldier.