“行动必须是普通的对象。 使用自定义中间件进行异步操作。“with react / redux

Question

I've encountered this error and spent the last few hours trying to figure it out. I've looked at all the questions that appear to be duplicates - but they don't solve the issue.

In my react/redux app, when I made an ajax request in one of my actions, it throws this error out: Uncaught Error: Actions must be plain objects. Use custom middleware for async actions. Uncaught Error: Actions must be plain objects. Use custom middleware for async actions.

My store creation looks like this:

 import { composeWithDevTools } from 'redux-devtools-extension'; import reducers from './reducers'; import thunkMiddleware from 'redux-thunk'; import { applyMiddleware, createStore } from 'redux'; export default createStore(reducers, composeWithDevTools( applyMiddleware(thunkMiddleware) )); 

The relevant reducer looks like this:

 import * as actions from './../../actions/tools/vehicle-lookup'; const defaultState = { vrm: void 0, isLoading: false, response: void 0, error: void 0, }; export default function (state = defaultState, action) { switch (action.type) { case actions.VEHICLE_LOOKUP: return { ...state, isLoading: true, vrm: action.vrm }; case actions.VEHICLE_LOOKUP_SUCCESS: return { ...state, isLoading: false, payload: action.payload, error: void 0 }; case actions.VEHICLE_LOOKUP_FAILURE: return { ...state, isLoading: false, error: action.error, response: void 0 }; default: return state; } } 

The relevant action looks like this:

 import axios from 'axios'; export const VEHICLE_LOOKUP = 'VEHICLE_LOOKUP'; export const VEHICLE_LOOKUP_SUCCESS = 'VEHICLE_LOOKUP_SUCCESS'; export const VEHICLE_LOOKUP_FAILURE = 'VEHICLE_LOOKUP_FAILURE'; export function fetchVehicleLookup(vrm: string, jwt: string) { return function (dispatch) { dispatch(requestVehicleLookup()); axios.create({ timeout: 4000, }) .post('/*api url*', { action: '*method*', body: { vrm }, }) .then(response => response.data) .then(json => dispatch(receiveVehicleData(json))) .catch(error => dispatch(receiveVehicleDataFailure(error))); }; } function requestVehicleLookup() { return { type: VEHICLE_LOOKUP }; } function receiveVehicleData(payload: object) { return { type: VEHICLE_LOOKUP_SUCCESS, payload }; } function receiveVehicleDataFailure(error: object) { return { type: VEHICLE_LOOKUP_FAILURE, error }; } 

My package versions are:

"axios": "^0.16.0",
"react": "^15.4.2",
"react-addons-css-transition-group": "^15.5.0",
"react-addons-transition-group": "^15.5.0",
"react-dom": "^15.4.2",
"react-hot-loader": "^3.0.0-beta.6",
"react-redux": "^5.0.3",
"react-router": "^4.0.0",
"react-router-dom": "^4.0.0",
"redux": "^3.6.0",
"redux-devtools-extension": "^2.13.0",
"redux-promise": "^0.5.3",
"redux-promise-middleware": "^4.2.0",
"redux-thunk": "^2.2.0",

Answer 1

First thought was that your fetchVehicleLookup action was moaning because you are returning the axios instead of just dispatching within.

export function fetchVehicleLookup(vrm: string, jwt: string) {
    return function (dispatch) {
        dispatch(requestVehicleLookup());

        axios.create({
            timeout: 4000,
        })
            .post('/*api url*', {
                action: '*method*',
                body: { vrm },
            })
            .then(response => response.data)
            .then(json => dispatch(receiveVehicleData(json)))
            .catch(error => dispatch(receiveVehicleDataFailure(error)));
    };
}

Simply remove the return statement that is in your action, as it's returning whatever object axios represents, which I imagine is going to be some form of Promise .

Second thought could be something around your store setup because it sounds like thunk isn't actually working.

Answer 2

I managed to figure it out - after a very long chat with @Glitch100 (thanks!). I needed to return the dispatch of requestVehicleLookup just after the axios promise was created. Like so:

 export function fetchVehicleLookup(vrm: string, jwt: string) { return function (dispatch) { axios.create({ timeout: 4000, }) .post('/*api url*', { action: '*method*', body: { vrm }, }) .then(response => response.data) .then(json => dispatch(receiveVehicleData(json))) .catch(error => dispatch(receiveVehicleDataFailure(error))); return dispatch(requestVehicleLookup()); }; }