162

I am trying to switch an app I am building over to use Redux Toolkit, and have noticed this error coming up as soon as I switched over to configureStore from createStore:

A non-serializable value was detected in the state, in the path: `varietals.red.0`. Value:, Varietal {
  "color": "red",
  "id": "2ada6486-b0b5-520e-b6ac-b91da6f1b901",
  "isCommon": true,
  "isSelected": false,
  "varietal": "bordeaux blend",
}, 
Take a look at the reducer(s) handling this action type: TOGGLE_VARIETAL.
(See https://redux.js.org/faq/organizing-state#can-i-put-functions-promises-or-other-non-serializable-items-in-my-store-state)

After poking around I found the issue seems to be with my custom models. For example the varietals array is created from a varietal model:

class Varietal {
  constructor(id, color, varietal, isSelected, isCommon) {
  this.id = id;
  this.color = color;
  this.varietal = varietal;
  this.isSelected = isSelected;
  this.isCommon = isCommon;
 }
}

and using that I map over an array of strings to create my Varietal array which goes into my state:

// my utility function for creating the array
const createVarietalArray = (arr, color, isCommon) =>
  arr.map(v => new Varietal(uuidv5(v, NAMESPACE), color, v, false, isCommon));';

// my array of strings
import redVarietals from '../constants/varietals/red';

// the final array to be exported and used in my state
export const COMMON_RED = createVarietalArray(redVarietals.common.sort(), 'red', true);

When I switched out the model and replaced the array creating utility with something that returned a plain array of objects like this:

export const createVarietalArray = (arr, color, isCommon) =>
  arr.map(v => ({
    id: uuidv5(v, NAMESPACE),
    color,
    varietal: v,
    isSelected: false,
    isCommon,
  }));

then that got the error to go away for that PARTICULAR reducer, however I have these custom models all through my app and before I start ripping them all out and recoding them simply to be able to use the Redux Toolkit I wanted to ask here if that is REALLY what the issue is before I did that...

Hazy
  • 1,766
  • 2
  • 8
  • 12

13 Answers13

157

This is more likely a problem from redux-persist. redux-toolkit provide few default middleware within it's getDefaultMiddleware

import { getDefaultMiddleware } from '@reduxjs/toolkit';

You can disable each middleware by providing false flag. To remove serializableCheck

const customizedMiddleware = getDefaultMiddleware({
  serializableCheck: false
})

For details check redux-toolkit documentation.

[2021/10/07] edit:

To learn more about why this error happens, and why setting serializableCheck to false fixes it, read Working with Non-Serializable Data | Usage Guide redux toolkit docs.

Additionally, the getDefaultMiddleware export is being deprecated in favor of using a callback form. See Future planning: RTK 2.0? · Issue #958 · reduxjs/redux-toolkit and getDefaultMiddleware deprecated · Issue #1324 · reduxjs/redux-toolkit to learn more about why.

As to what it's being replaced with, see the getDefaultMiddleware | Redux Toolkit documentation to learn more:

import { configureStore } from '@reduxjs/toolkit'

import rootReducer from './reducer'

const store = configureStore({
  reducer: rootReducer,
  middleware: (getDefaultMiddleware) => getDefaultMiddleware(),
})
sgarcia.dev
  • 5,671
  • 14
  • 46
  • 80
Rahad Rahman
  • 1,847
  • 2
  • 13
  • 11
  • 7
    Anyone seeing this and working with redux-persist, do not entirely disable the serializable check unless you know what you're doing. It's better to specifically disable the actions from redux-persist. [See the answer from @AmerllicA](https://stackoverflow.com/a/62610422/5026438) – Chase Ingebritson Jun 05 '21 at 21:54
  • In my case it is probably caused by `redux-saga`: `A non-serializable value was detected in an action, in the path: `type`. Value: ƒ actionCreator() { var args = []; for (var _i = 0; _i < arguments.length; _i++) { args[_i] = arguments[_i]; } if (prepareAction) ` Option above suppressed the error but I don't think it is correct workaround. – Dron007 Jul 05 '21 at 17:28
  • 1
    getDefaultMiddleware is now deprecated, see answer https://stackoverflow.com/a/68509710/10765649 from boluwatife-fakorede – Dako Junior Aug 24 '21 at 05:09
  • Thanks for the heads up @DakoJunior, edited the answer to include links to why it's being deprecated, and how to use the new callback syntax. – sgarcia.dev Oct 07 '21 at 17:12
  • 1
    Is it ok to put instances of AbortController in the redux store? – Tony I. Mar 20 '22 at 01:37
  • 1
    If someone is encountering this issue in the context of redux-persist, this is how you do it: https://redux-toolkit.js.org/usage/usage-guide#use-with-redux-persist – Ashtrix May 21 '22 at 01:14
83

Yes. We've always told Redux users they should not put non-serializable values in the store. Redux Toolkit was specifically designed to help provide good defaults when setting up a Redux store, and as part of that, it includes checks to make sure you're not accidentally mutating your data and that you're not including non-serializable values.

Class instances are by definition not fully serializable, so it's correctly flagging those instances as a problem. Please rewrite your logic to not pass those in to the store.

In general, React and Redux apps should be written using only plain JS objects and arrays as data. You don't need "model classes".

markerikson
  • 63,178
  • 10
  • 141
  • 157
  • 8
    Um. I have no idea why you felt the need to drop this comment, on an answer I wrote a year ago. Ultimately it's _your_ codebase, and you can do whatever you want with it. But as a general rule, React ecosystem apps don't use model classes, and Redux _has_ always been very opinionated about not allowing classes in the Redux store state. So, that's the advice we give to people. – markerikson Mar 16 '21 at 20:56
  • 2
    Wouldn't be nice to add a way to control the serialization and thus allowing to store every value type we want and/or need? – MatteoSp Apr 26 '21 at 15:30
  • 2
    You can [customize the behavior of the serialization check middleware](https://redux-toolkit.js.org/api/serializabilityMiddleware) if desired, including overriding the "what values are serializable?" callback or turning it off entirely. However, we **strongly recommend that you do not do that**. Ultimately it's your app and you can do whatever you want, but these guidelines exist for a reason. – markerikson Apr 26 '21 at 15:38
  • Thanks! Already seen this, and thought it wasn't what I need: I expected to find a way to convert my classes to/from string. Am I missing something? – MatteoSp Apr 27 '21 at 06:58
  • Uh... no, we don't do any serialization of values ourselves. Redux state is ultimately "just" a normal JS variable. But, viewing Redux state via the DevTools requires that the state be serialized out to the extension, and cases like persistence require the state to be serialized as well. Additionally, storing class instances implies mutable state updates, which are not allowed in Redux. So, we're trying to block people from making that sort of mistake. I'd strongly suggest that you try to find a different approach to working with your data in Redux. – markerikson Apr 27 '21 at 14:39
  • And given a large (I mean very large) set of typescript classes already in place that we want to use as state and that have many properties of Date type, which approach would you recommend? – MatteoSp Apr 28 '21 at 08:13
  • 1
    In all honesty, in that case you may not want to use Redux :) – markerikson Apr 28 '21 at 14:06
  • 1
    To add to what Mark said regarding how to solve this by overriding Redux's serialization behavior, the Redux Toolkit docs on _Working with Non-Serializable Data_ are a great read that further explains why this issue happens, and how to apply a fix to the specific part of your redux application that is causing it: https://redux-toolkit.js.org/usage/usage-guide#working-with-non-serializable-data – sgarcia.dev Oct 07 '21 at 17:32
  • JavaScript "Set" is still not recognized and shows this warning all the time. I think we can now extend this to include Set and other new data structures apart from arrays. – XPD Jan 14 '22 at 17:43
  • Correct. `Map`, `Set`, `Date`, and classes are all considered "non-serializable values" by default. – markerikson Jan 14 '22 at 19:55
  • @markerikson Thank you, i don't understand until now why i got this error! and because of the explanation you wrote, now i understand very well! so thx. – Roni Jack Vituli Aug 22 '22 at 13:44
67

With the getDefaultMiddleware getting depreciated, this can be resolved by using

   middleware: getDefaultMiddleware =>
    getDefaultMiddleware({
      serializableCheck: false,
    }),
41

I faced this issue on React Native when I wanted to implement redux-persist alongside @reduxjs/toolkit, and I got this error:

enter image description here

Then I fixed it by following code:

import {
  combineReducers,
  configureStore,
  getDefaultMiddleware,
} from '@reduxjs/toolkit';
import {
  persistStore,
  persistReducer,
  FLUSH,
  REHYDRATE,
  PAUSE,
  PERSIST,
  PURGE,
  REGISTER,
} from 'redux-persist';
import storage from 'utils/storage'; // in fact it is AsyncStorage
import counter from 'reduxStore/reducers';

const persistConfig = {
  key: 'root',
  storage,
};

const reducer = combineReducers({
  counter,
});

const persistedReducer = persistReducer(persistConfig, reducer);

const store = configureStore({
  reducer: persistedReducer,
  middleware: getDefaultMiddleware({
    serializableCheck: {
      ignoredActions: [FLUSH, REHYDRATE, PAUSE, PERSIST, PURGE, REGISTER],
    },
  }),
});

export const persistor = persistStore(store);

export default store;

Actually, these lines help me, without them I got above error:

middleware: getDefaultMiddleware({
  serializableCheck: {
    ignoredActions: [FLUSH, REHYDRATE, PAUSE, PERSIST, PURGE, REGISTER],
  },
}),
zero_cool
  • 3,960
  • 5
  • 39
  • 54
AmerllicA
  • 29,059
  • 15
  • 130
  • 154
  • 10
    This is consistent with the RTK docs: https://redux-toolkit.js.org/usage/usage-guide#use-with-redux-persist – Bondolin Mar 02 '21 at 02:23
  • 2
    I did the same thing but i get the same error. – Dijiflex Jul 10 '21 at 11:13
  • 4
    @Dijiflex, I hope and pray your issue will be settled. – AmerllicA Jul 10 '21 at 11:53
  • @Dijiflex same for me even after I re-start my local server, but somehow the warnings disappeared after several trials of restart. – Changdae Park Nov 12 '22 at 16:41
  • Awesome, thanks @AmerllicA!! Sounds better than skipping all the actions with `serializableCheck: false` – Alan Bueno Dec 30 '22 at 15:22
  • This should definitely be the accepted answer for this issue. `serializableCheck: false` is just a bandaid. Instead, passing only the specific actions used by `redux-persist` is consistent with the redux toolkit docs and the correct (and specific) fix to the warning. – fullStackChris Jan 10 '23 at 08:48
  • The FLUSH, REHYDRATE, PAUSE, PERSIST, PURGE, and REGISTER action types are all related to the redux-persist library, which is used to persist your Redux state between sessions. These actions are used internally by redux-persist and do not need to be serializable, which is why they are included in the ignoredActions array. – Fotios Tsakiris Mar 25 '23 at 08:40
25

This example shows excluding the serializable state check middleware enter link description here

 const store = configureStore({
  reducer: rootReducer,
  middleware: (getDefaultMiddleware) =>
    getDefaultMiddleware({
      serializableCheck: false,
    }),
})
Omar
  • 251
  • 3
  • 2
10

Check the RTK docs on how to set it up with Redux Persist.

https://redux-toolkit.js.org/usage/usage-guide#use-with-redux-persist

Basically it's just this line:

middleware: getDefaultMiddleware =>
    getDefaultMiddleware({
      serializableCheck: {
        ignoredActions: [FLUSH, REHYDRATE, PAUSE, PERSIST, PURGE, REGISTER],
      },
    })

Which is in the configureStore call.

Also, you need this:

import {
  persistStore,
  persistReducer,
  FLUSH,
  REHYDRATE,
  PAUSE,
  PERSIST,
  PURGE,
  REGISTER,
} from 'redux-persist'
Mark Lopez
  • 770
  • 1
  • 6
  • 10
  • And combining it with this another solution is even better https://github.com/vercel/next.js/discussions/15687#discussioncomment-45319 – shimo Dec 31 '22 at 17:11
5

I added 'middleWare' parameter with 'serializableCheck: false,' problem solved. (it is not a problem actually)

source: link

 import { configureStore } from '@reduxjs/toolkit'
    import rootReducer from './reducer'
    import { myCustomApiService } from './api'
    
    const store = configureStore({
      reducer: rootReducer,
      middleware: (getDefaultMiddleware) =>
        getDefaultMiddleware({
          serializableCheck: false,
        }),
    })
Burak Ozcelik
  • 101
  • 1
  • 6
3

I think the following is the best option if you know exactly what it is that is non-serializable but that you need in the reducer anyway:

const store = configureStore({
    reducer: { reducer },
    middleware: getDefaultMiddleware => getDefaultMiddleware({
        serializableCheck: {
            ignoredActions: ['TYPE'],
            ignoredActionPaths: ['property'],
            ignoredPaths: ['reducer.property']
        }
    })
});

For errors thrown in the action, either ignoredActions or ignoredActionPaths is enough. For errors thrown in the state, use ignoredPaths. Check the error message to see the names that you need to provide.

Just like @ReFruity , my issue appeared because I was keeping the AbortController there.

EDIT: Just an aside as, in order for the AbortController to work, I stored in the reducer just the signal and the abort method and I had to do this for it to work:

let abortMethod = abortController.abort.bind(abortController);

Otherwise I was getting an error about illegal invocation.

GuiRitter
  • 697
  • 1
  • 11
  • 20
2

One of the core usage principles for Redux is that you should not put non-serializable values in state or actions.

However, like most rules, there are exceptions. However, if you do need to turnoff those warnings, you can customize the middleware by configuring it to ignore specific action types, or fields in actions and state:

configureStore({
  //...
  middleware: (getDefaultMiddleware) =>
    getDefaultMiddleware({
      serializableCheck: {
        ignoredActions: ['your/action/type'],  
      },
    }),
})

your/action/type should be replaced with actual action type which you will see in your warning message.

Reference: https://redux-toolkit.js.org/usage/usage-guide#working-with-non-serializable-data

Tapas Vashi
  • 231
  • 2
  • 5
0

I had the same problem and I solved it this way

you can just add a middleWare and pass it to configureStore

import { rootReducer } from "./root-reducer";
import { configureStore } from "@reduxjs/toolkit";
import logger from "redux-logger";
const middleWares = [logger];

export const store = configureStore({
  reducer: rootReducer,
  middleware: middleWares,
});
0
    getDefaultMiddleware({
      serializableCheck: {
        ignoredActions: [FLUSH, REHYDRATE, PAUSE, PERSIST, PURGE, REGISTER],
      },
    }),

import these flush purge etc from redux-persist and add the middleware to configure store! The issue would be solved!

Ahmet Emre Kilinc
  • 5,489
  • 12
  • 30
  • 42
Sahad
  • 1
0

If you are using axios in your createAsyncThunk method just return response,

createAsyncThunk(
  "post/getPost",
  async ({ id }) => {
    return axios
      .get(`https://jsonplaceholder.typicode.com/posts/${id}`)
      .then((res) => res);
  }
);
Mishen Thakshana
  • 1,050
  • 1
  • 14
  • 38
0

As you know core use for Redux is that you should not put non-serializable values in state or actions.

But here we have an exceptions that there may be occasions when you have to deal with actions that need to accept non-serializable data but we need to make sure that these non-serializable payloads shouldn't ever make it into your application state through a reducer.

The serializability middleware will automatically warn anytime it detects non-serializable values in your actions or state. If you do need to turnoff those warnings, you can customize the middleware by configuring it to ignore specific action types, or fields in actions and state:

Note: It is recommended that to leave this middleware active to help avoid accidentally making mistakes.

configureStore({
  //...
  middleware: (getDefaultMiddleware) =>
    getDefaultMiddleware({
      serializableCheck: {
        // Ignore these action types
        ignoredActions: ['your/action/type'],
        // Ignore these field paths in all actions
        ignoredActionPaths: ['meta.arg', 'payload.timestamp'],
        // Ignore these paths in the state
        ignoredPaths: ['items.dates'],
      },
    }),
})

More Detailed Explanation:

  1. https://redux-toolkit.js.org/usage/usage-guide#working-with-non-serializable-data
  2. https://redux.js.org/faq/actions#why-should-type-be-a-string-or-at-least-serializable-why-should-my-action-types-be-constants
geekfarmer
  • 99
  • 2
  • 7