Why am i getting "Error: Actions must be plain objects. Use custom middleware for async actions." error? - redux

Question

I am continuously getting " Actions must be plain objects. Use custom middleware for async actions." error and I am totally stuck here. What am I doing wrong here please help me figure out and help me get out of this error.
This is my index.js file where I have integrated redux store to the app.
import "babel-polyfill";
import React from 'react';
import ReactDOM from 'react-dom';
import { BrowserRouter as Router } from 'react-router-dom';
import { Provider } from 'react-redux'
import { composeWithDevTools } from 'redux-devtools-extension';
import { createStore, applyMiddleware, combineReducers, compose} from 'redux'
import createSagaMiddleware from 'redux-saga'
import rootSaga from './sagas'
import { postsReducer } from './reducers/posts'
import Routes from './routes';
import './styles/style.css'
const rootReducer = combineReducers({ postsReducer })
const sagaMiddleware = createSagaMiddleware()
const store = createStore(rootReducer, composeWithDevTools(applyMiddleware(sagaMiddleware)))
sagaMiddleware.run(rootSaga)
ReactDOM.render((
<Provider store={store}>
<Router><Routes /></Router>
</Provider>
), document.getElementById('root'))
this is my saga.js
import { take, put, call, fork, select, takeEvery, all, takeLatest } from 'redux-saga/effects'
import PostApi from './api/postApi';
import { gotPosts } from './actions/celebrity';
import { POSTS } from '../types'
export function* getAllPosts () {
const posts = yield call(PostApi.getPosts, {})
console.log('postssss', posts)
yield put(gotPosts(posts.data))
}
export function* watchGetPosts () {
yield takeLatest(POSTS, getAllPosts)
}
export default function* root() {
yield all([ fork(watchGetPosts) ])
}
this is my action.js
import { POSTS } from '../../types';
export const gotPosts = (data) => {
return {
type: POSTS,
data,
}
}
export const getPosts = () => dispatch => {
dispatch(gotPosts);
}
this is component page where i dispatched action.
import React, { Component } from 'react';
import { Card, Row, Col } from 'antd';
import { Link } from 'react-router-dom';
import { connect } from 'react-redux'
import { getPosts } from '../actions/celebrity';
const { Meta } = Card;
class MainPage extends Component {
componentDidMount () {
console.log(this.props)
this.props.getPosts();
}
render() {
return <Row type="flex" className="main" justify="center" align="between">
......
</Row>
}
}
const mapStateToProps = state => {
return {
posts: state.postsReducer
}
}
const mapDispatchToProps = dispatch => ({
getPosts: () => {
dispatch(getPosts());
},
});
export default connect(mapStateToProps, mapDispatchToProps)(MainPage);
postsReducer
export const postsReducer = (state = [], action) => {
console.log(action)
switch(action.type){
case POSTS:
return action.data;
default:
return state;
}
}

Answer 1

You can't dispatch function w/o middleware support.
Problem originates from mapDispatchToProps:
{
getPosts: () => { dispatch(getPosts()); }
}
tracing down to your actions.js, getPosts() returns dispatch => dispatch(gotPosts), which is actually a function not an action(plan javascript object), redux dispatch by default doesn't recognize functions, unless you use middleware to enhance it, redux thunk for example.
Since you already have redux saga for async flow, simply dispatch an action from mapDispatchToProps should be fine, also consider create separate actions to differentiate POSTS_REQUEST, POSTS_RECEIVE, POSTS_FAILURE if possible.
import {POST} from '....../actionTypes'
...
{
getPosts: () => { dispatch({ type: POST }); }
}