Where to dispatch multiple actions in redux?

问题:

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.

回答1:

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)

---

回答2:

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))
  }
}

回答3:

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)));

回答4:

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)
    ]))
});

回答5:

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())])
}

回答6:

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.