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How to retrieve object after post in react redux from api

I created a Todo application in React.js. I have an API to store my todos and their states.
In my application I can drag and drop the todos in the state I want and I can also CRUD the states.
For the state part I use React-Redux.
My problem happens when adding a new state, I would like to get the id that is provided by the API but in my reducer I get this error: A non-serializable value was detected in the state, in the path: stateReducer.
If I don't get the id, I can't delete the state cause I delete by id, I have to reload the page.
To initialize my state list I use a middleware to do the asymmetric part but I don't understand how to do it when I add a new object.
import { createAsyncThunk, createSlice } from "#reduxjs/toolkit";
import Api from "../api/Api.ts";
const api = new Api("http://localhost:3333/api/state/")
const initialState = {
status:'idle',
list:[],
error: null
}
export const StateSlice = createSlice({
name:'status',
initialState,
reducers: {
add: async (state, action) => {
let item
await api.post(action.payload).then(state => item = state) // PROBLEME
state.list.push(item)
},
remove:(state, action) => {
state.list.splice(state.list.indexOf(action.payload),1)
api.del(action.payload)
},
update:(state, action) => {
api.update(action.payload)
},
get: async (state,action) => {
state.list = action.payload
},
},
extraReducers(builder) {
builder
.addCase(fetchPosts.pending, (state, action) => {
state.status = 'loading'
})
.addCase(fetchPosts.fulfilled, (state, action) => {
state.status = 'succeeded'
state.list = state.list.concat(action.payload)
})
.addCase(fetchPosts.rejected, (state, action) => {
state.status = 'failed'
state.error = action.error.message
})
}
})
const getPosts = async () => {
const states = []
let posts = await api.get()
posts.forEach(p => {
states.push({id:p.id,name:p.name})
});
return states
}
export const fetchPosts = createAsyncThunk('state/fetchPosts', async () => {
let response = await getPosts()
return response
})
export const {add, remove, update, get} = StateSlice.actions
export default StateSlice.reducer;
Do I need to create another middleware for this and how call it ? I am new to this technology, can you give me a hint please?

Redux Toolkit createSlice in React

I'm learning Redux-Saga and everything works well with { configureStore, getDefaultMiddleware, createAction, createReducer }. However, I cannot successfully implement createSlice.
My actions seem to be dispatched just fine (though I'm not sure since I have multiple Redux stores and placing console.log inside createSlice doesn't seem to work...). I just cannot get the store values - after dispatched action the relevant state value (initially '') becomes undefined. I did wrap my component inside Provider and all. Can someone enlighten me how does createSlice work? Thanks.
RESOLVED I had a bug somewhere else in my code, that's why the reducers weren't working proberly. BUT what I was asking about and what was causing my problems is this: actions passed to createSlice must be 'pure' functions, meaning: (state, action) -> state, nothing fancy. That's why I had to remove my fetching functions (getData1 and getData2) from this createSlice.
ComponentWrapper returns this
<Provider store={toolkitCreateSliceStore}>
<ReduxToolkitCreateSliceComponent />
</Provider>
Component (Buttons just dispatch actions)
class ReduxToolkitCreateSliceComponent extends React.Component {
render () {
return (
<>
<h2>
{this.props.data1}
{(this.props.data1!=='' && this.props.data2!=='') ? ', ' : ''}
{this.props.data2}
</h2><br/>
<h3>{this.props.message}</h3>
<Button1 />
<Button2 />
<Button3 />
</>
);
}
}
function mapStateToProps(state) {
return {
data1: state.toolkitCreateSliceReducer.data1,
data2: state.toolkitCreateSliceReducer.data2,
message: state.toolkitCreateSliceReducer.message
};
}
export default connect(mapStateToProps)(ReduxToolkitCreateSliceComponent);
Redux Toolkit slice
import { createSlice } from "#reduxjs/toolkit";
import axios from "axios";
const initialSliceState = {
data1: '',
data2: '',
message: ''
};
const slice = createSlice({
name: "slice",
initialState: initialSliceState,
reducers: {
getData1: (state, action) => {
return dispatch => {
dispatch(loading1());
return axios.get('http://localhost:8081/data1')
.then(function (response) {
if (response.status === 200) {
dispatch(setResponse1(response.data));
}
}).catch(error => dispatch(displayError1(error)));
};
},
getData2: (state, action) => {
return dispatch => {
dispatch(loading2());
return axios.get('http://localhost:8081/data2')
.then(function (response) {
if (response.status === 200) {
dispatch(setResponse2(response.data));
}
}).catch(error => dispatch(displayError2(error)));
};
},
setResponse1: (state, action) => {
state.data1 = action.payload;
state.message = 'success';
},
setResponse2: (state, action) => {
state.data2 = action.payload;
state.message = 'success';
},
reset: (state, action) => {
state.data1 = '';
state.data2 = '';
state.message = 'reset';
},
loading1: (state, action) => {
state.message = 'loading';
},
loading2: (state, action) => {
state.message = 'loading';
},
displayError1: (state, action) => {
state.message = action.payload;;
},
displayError2: (state, action) => {
state.message = action.payload;;
}
}
});
export const toolkitCreateSliceReducer = slice.reducer;
const { getData1, getData2, setResponse1, setResponse2, reset, loading1, loading2,
displayError1, displayError2} = slice.actions;
export default slice;
Redux Toolkit store
const middleware = [
...getDefaultMiddleware()
];
const toolkitCreateSliceStore = configureStore({
reducer: {
toolkitCreateSliceReducer
},
middleware
});
export default toolkitCreateSliceStore;

Your "reducers" are very wrong.
A reducer must never have any side effects like AJAX calls.
You've written some Redux "thunk" functions where your reducers should be:
getData1: (state, action) => {
return dispatch => {
dispatch(loading1());
return axios.get('http://localhost:8081/data1')
.then(function (response) {
if (response.status === 200) {
dispatch(setResponse1(response.data));
}
}).catch(error => dispatch(displayError1(error)));
};
},
This is a thunk, not a reducer.
A reducer would be something like:
getData(state, action) {
return action.payload;
}
I'd specifically recommend reading through our brand-new "Redux Essentials" core docs tutorial, which teaches beginners "how to use Redux, the right way", using our latest recommended tools and practices like Redux Toolkit. It specifically covers how reducers should work, how to write reducers with createSlice, and how to write and use thunks alongside createSlice:
https://redux.js.org/tutorials/essentials/part-1-overview-concepts

If you're interested in creating async actions, let me recommend you an npm package that I created and use. It is saga-toolkit that allows async functions to get resolved by sagas.
slice.js
import { createSlice } from '#reduxjs/toolkit'
import { createSagaAction } from 'saga-toolkit'
const name = 'example'
const initialState = {
result: null,
loading: false,
error: null,
}
export const fetchThings = createSagaAction(`${name}/fetchThings`)
const slice = createSlice({
name,
initialState,
extraReducers: {
[fetchThings.pending]: () => ({
loading: true,
}),
[fetchThings.fulfilled]: ({ payload }) => ({
result: payload,
loading: false,
}),
[fetchThings.rejected]: ({ error }) => ({
error,
loading: false,
}),
},
})
export default slice.reducer
sagas.js
import { call } from 'redux-saga/effects'
import { takeLatestAsync } from 'saga-toolkit'
import API from 'hyper-super-api'
import * as actions from './slice'
function* fetchThings() {
const result = yield call(() => API.get('/things'))
return result
}
export default [
takeLatestAsync(actions.fetchThings.type, fetchThings),
]

Data sent from service-file is not updated in Reducer State

I am like in a strange problem. The problem is that I am trying to make an API hit (in service file) which in turn provides some data (it is working), this data is to be updated in my reducer1.js and then returned. Now, my issue is though the value is coming in reducer file, but is not returned, so in turn, state is not changed, and in turn my end component is not rerendered.
Now, when my service file is successfully hitting and then returning data to my reducer1.js, why in the world the updated-state is not returned by "GET_List" action type? Can someone see any problem?
index.js (service file)
const global = {
getActressList: async function(){
const response = await fetch("http://localhost:2000/api/actressList");
const data = await response.json();
return data;
}
}
export default global;
reducer1.js
import global from '../../services/index';
const initialState = {
data: [
{
id: 1,
name: "Aishwarya Rai",
src: "/assets/img/aishwarya.png"
}
]
};
function reducer1(state = initialState, action) {
switch (action.type) {
case "GET_LIST": {
const data = global.getActressList();
data.then((res)=> {
return {
...state,
data: res
}
})
}
default:
return state;
}
}
export default reducer1;
Result:

You are returning from a promise not from a reducer function:
function reducer1(state = initialState, action) {
switch (action.type) {
case "GET_LIST": {
const data = global.getActressList();
data.then((res) => {
// here you are returning from a promise not from a reducer function
return {
...state,
data: res,
};
});
}
default:
return state;
}
}
The code in reducer should be sync like this:
function reducer1(state = initialState, action) {
switch (action.type) {
case "GET_LIST": {
return {
...state,
data: action.payload,
};
}
default:
return state;
}
}
And your data fetching should be moved to component effect like this:
function YourComponent() {
const dispatch = useDispatch();
const data = useSelector(state => state.data)
useEffect(() => {
const data = global.getActressList();
data.then((res) => {
dispatch({type: 'GET_LIST', payload: res});
});
}, [])
...
}
EDIT
If you use class components the fetching logic should be placed in componentDidMount lifecycle hook like this:
class YourComponent extends Component {
state = { data: [] };
componentDidMount() {
const data = global.getActressList();
data.then((res) => {
dispatchYourAction({type: 'GET_LIST', payload: res});
});
}
...
}

When an action is dispatched, state of another reducer is removed. Why?

I use Redux in my project for first time. I have multiple reducers and and actions. When the first action is dispatched, state is changed. It looks okey. After dispatching second action, state is changed again but the previous changes are removed. I mean, when 'FETCH_COMPANY_INFORMATIONS' is dispatched companyName is changed and companyDesc set to initial value. Then 'FETCH_INITIAL_MEMBER' is dispatched and companyName is removed but companyDesc is still there and member payloads are also changed. What is my mistake? Thanks.
I tried many ways to solve this but still continue. I check this on Redux DevTools.
memberReducer
const initialState = {
username: '',
companyId: '',
isAdmin: '',
photo: '',
};
export default (state = initialState, action) => {
switch (action.type) {
case FETCH_INITIAL_MEMBER:
return {
...state,
username: action.payload.username,
companyId: action.payload.companyId,
isAdmin: action.payload.isAdmin,
};
default:
return state;
}
};
companyReducer
const initialState = {
companyName: 'companyName',
companyDesc: 'companyDesc',
};
export default (state = initialState, action) => {
switch (action.type) {
case FETCH_COMPANY_INFORMATIONS:
return {
...state,
companyName: action.payload.companyName,
};
default:
return state;
}
};
memberAction
const fetchInıtıalMember = async muuid => {
axios
.get(`/api/member/${muuid}`)
.then(response => {
const username = response.data.mname;
const isAdmin = response.data.misAdmin;
const companyId = response.data.cid;
store.dispatch({
type: FETCH_INITIAL_MEMBER,
payload: {
username,
isAdmin,
companyId,
},
});
})
.catch(error => {});
};
companyAction
const fetchCompanyInformations = () => {
store.dispatch({
type: FETCH_COMPANY_INFORMATIONS,
payload: { companyName: 'dispacthedCompanyName' },
});
};
Edit:
The code above is correct. My mistake is about importing the constants. This Redux implementation works well. I was storing all action type constant in a types.js file. I import this type constants in the another files wrongly. After changing it my problem is solved.

Accessing a part of reducer state from one reducer within another reducer

I do not know how to access a boolean isLoading flag from reducerForm.js reducer in reducerRegister.js. I have used combineReducers() and I use isLoading to disable a button during form submit.
It's initial state is false, after clicking submit, it changes to true. After the form submission is successful, isLoading is reset to false again. Below is the relevant code for this issue:
actionRegister.js
let _registerUserFailure = (payload) => {
return {
type: types.SAVE_USER_FAILURE,
payload
};
};
let _registerUserSuccess = (payload) => {
return {
type: types.SAVE_USER_SUCCESS,
payload,
is_Active: 0,
isLoading:true
};
};
let _hideNotification = (payload) => {
return {
type: types.HIDE_NOTIFICATION,
payload: ''
};
};
// asynchronous helpers
export function registerUser({ // use redux-thunk for asynchronous dispatch
timezone,
password,
passwordConfirmation,
email,
name
}) {
return dispatch => {
axios.all([axios.post('/auth/signup', {
timezone,
password,
passwordConfirmation,
email,
name,
is_Active: 0
})
// axios.post('/send', {email})
])
.then(axios.spread(res => {
dispatch(_registerUserSuccess(res.data.message));
dispatch(formReset());
setTimeout(() => {
dispatch(_hideNotification(res.data.message));
}, 10000);
}))
.catch(res => {
// BE validation and passport error message
dispatch(_registerUserFailure(res.data.message));
setTimeout(() => {
dispatch(_hideNotification(res.data.message));
}, 10000);
});
};
}
actionForm.js
export function formUpdate(name, value) {
return {
type: types.FORM_UPDATE_VALUE,
name, //shorthand from name:name introduced in ES2016
value
};
}
export function formReset() {
return {
type: types.FORM_RESET
};
}
reducerRegister.js
const INITIAL_STATE = {
error:{},
is_Active:false,
isLoading:false
};
const reducerSignup = (state = INITIAL_STATE , action) => {
switch(action.type) {
case types.SAVE_USER_SUCCESS:
return { ...state, is_Active:false, isLoading: true, error: { register: action.payload }};
case types.SAVE_USER_FAILURE:
return { ...state, error: { register: action.payload }};
case types.HIDE_NOTIFICATION:
return { ...state , error:{} };
}
return state;
};
export default reducerSignup;
reducerForm.js
const INITIAL_STATE = {
values: {}
};
const reducerUpdate = (state = INITIAL_STATE, action) => {
switch (action.type) {
case types.FORM_UPDATE_VALUE:
return Object.assign({}, state, {
values: Object.assign({}, state.values, {
[action.name]: action.value,
})
});
case types.FORM_RESET:
return INITIAL_STATE;
// here I need isLoading value from reducerRegister.js
}
return state;
};
export default reducerUpdate;
reducerCombined.js
import { combineReducers } from 'redux';
import reducerRegister from './reducerRegister';
import reducerLogin from './reducerLogin';
import reducerForm from './reducerForm';
const rootReducer = combineReducers({
signup:reducerRegister,
signin: reducerLogin,
form: reducerForm
});
export default rootReducer;
This is where I use isLoading:
let isLoading = this.props.isLoading;
<FormGroup>
<Col smOffset={4} sm={8}>
<Button type="submit" disabled={isLoading}
onClick={!isLoading ? isLoading : null}
>
{ isLoading ? 'Creating...' : 'Create New Account'}
</Button>
</Col>
</FormGroup>
Mapping state to props within the same component
function mapStateToProps(state) {
return {
errorMessage: state.signup.error,
isLoading: state.signup.isLoading,
values: state.form.values
};
}

This is covered in the Redux FAQ at https://redux.js.org/faq/reducers#how-do-i-share-state-between-two-reducers-do-i-have-to-use-combinereducers:
Many users later want to try to share data between two reducers, but find that combineReducers does not allow them to do so. There are several approaches that can be used:
If a reducer needs to know data from another slice of state, the state tree shape may need to be reorganized so that a single reducer is handling more of the data.
You may need to write some custom functions for handling some of these actions. This may require replacing combineReducers with your own top-level reducer function. You can also use a utility such as reduce-reducers to run combineReducers to handle most actions, but also run a more specialized reducer for specific actions that cross state slices.
Async action creators such as redux-thunk have access to the entire state through getState(). An action creator can retrieve additional data from the state and put it in an action, so that each reducer has enough information to update its own state slice.

A reducer cannot access another reducer's state, but if you're using redux-thunk you can do so from within an action creator. As an example, you can define an action creator like this:
export const someAction = () =>
(dispatch, getState) => {
const someVal = getState().someReducer.someVal;
dispatch({ type: types.SOME_ACTION, valFromOtherReducer: someVal });
};

React Redux works on unidirectional data flow.
Action ---> Reducer /store ---> Reducer
Reducer works on small subset of store, you can not access store inside reducer which is not part of Reducer. you can either need to fire new action from the component based on reducer state return.