Action.type undefined redux - redux

Question

No matter what I do, I can't get rid of the mistake. I have often rewritten the actions but the error remains. I also wrote thunk at the top of the createstore. It would be great if you could support me a little bit.
My action, nothing special here only a fetch call to get my players
import fetch from "cross-fetch"
export const SET_PLAYERS = "setplayers"
export const setPlayers = players => {
return{
type: "setplayers",
players
}
}
export const fetchPlayers = () => (dispatch, getState) => {
return fetch("http://localhost:4444/api/players")
.then(response => response.json())
.then(players => {
dispatch(setPlayers(players))
}).catch(err => {
console.log("Could not fetch assortments" , err)
})
}
Component, at this point in time only a dummy to invoke the action:
import React from "react"
import PropTypes from "prop-types"
import { fetchPlayers } from "./action"
import { connect } from "react-redux"
import EnhancedTable from "../components/list/List"
import getPlayers from "./reducer"
class PlayerTable extends React.Component {
constructor(props) {
super(props)
this.state = {
}
}
componentDidMount(){
this.props.fetchPlayers()
}
render() {
console.log("#######", this.props.players)
return (
<EnhancedTable />
)
}
}
PlayerTable.propTypes = {
classes: PropTypes.object.isRequired,
}
const mapStateToProps = state => ({
players: getPlayers(state)
})
export default connect(mapStateToProps, { fetchPlayers })(PlayerTable)
Reducer
import { SET_PLAYERS } from "./action"
const setPlayers = (state={}, action) => {
console.log("ACTION", action)
switch (action.type) {
case SET_PLAYERS:
return {...state, players: action.players}
default:
return state
}
}
export default setPlayers
export const getPlayers = state => ([])
CombinedReducers
import { combineReducers } from "redux"
import { reducer as formReducer } from "redux-form"
import showProgressbar from "../components/progressbar/reducer"
import showSnackBar from "../components/snackbar/reducer"
import setPlayers from "../player/reducer"
export default combineReducers({
form: formReducer,
showProgressbar,
showSnackBar,
setPlayers
})
CreateStore
import App from "./App"
import React from "react"
import rootReducer from "./reducers"
import thunk from "redux-thunk"
import { render } from "react-dom"
import { createStore, applyMiddleware, compose } from "redux"
import { Provider } from "react-redux"
import { createLogger } from "redux-logger"
const store = createStore(
rootReducer,
compose(applyMiddleware(thunk),
window.__REDUX_DEVTOOLS_EXTENSION__ && window.__REDUX_DEVTOOLS_EXTENSION__()
))
render(
<Provider store={store}>
<App />
</Provider>,
/* eslint-disable*/
document.getElementById("root")
/* eslint-enable */
)

Answer 1

You've defined mapStateToProps properly, but don't you need to do the same with mapDispatchToProps for the second argument to connect()?
const mapStateToProps = state => ({
players: getPlayers(state)
})
const mapDispatchToProps = dispatch => ({
fetchPlayers() {
dispatch(fetchPlayers())
}
})
export default connect(mapStateToProps, mapDispatchToProps)(PlayerTable)