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👻 Primitive and flexible state management for React
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---title: Devtoolsdescription: This doc describes Devtools for Jotai.nav: 5.03keywords: devtools,debug,snapshot---
### Install
Install `jotai-devtools` to your project to get started.
```shnpm i jotai-devtools @emotion/react```
### Notes
- `<DevTools/>` is optimized to be tree-shakable for production builds, and **only works in a non-production environment**- Hooks are dev-only, and are designed to work in a non-production environment- Feedback welcome, please file issues or ask questions on the [Jotai DevTools GitHub Repo](https://github.com/jotaijs/jotai-devtools/discussions)### Quick links
- [UI Devtools](#ui-devtools)- Hooks - [useAtomsDebugValue](#useatomsdebugvalue) - [useAtomDevtools](#useatomdevtools) - [useAtomsDevtools](#useatomsdevtools) - [useAtomsSnapshot](#useatomssnapshot) - [useGotoAtomsSnapshot](#usegotoatomssnapshot)### UI DevTools
Enhance your development experience with the UI based Jotai DevTool.
#### Babel plugin setup - (_Optional but highly recommended_)
Use Jotai babel plugins for optimal debugging experience. Find the complete guide on the [babel](../tools/babel) page and/or [swc](../tools/swc) page.
Example:
```ts{ "presets": [ // The preset includes two plugins: // - jotai/babel/plugin-react-refresh to enable hot reaload for atoms // - jotai/babel/plugin-debug-label to automatically adds debug labels to atoms 'jotai/babel/preset' ]}```
Example for Vite + React project:
```ts// vite.config.ts
export default defineConfig({ plugins: [ react({ babel: { presets: ['jotai/babel/preset'], }, }), ],})```
### Next JS setup
_You may skip this section if you're not using [Next.js](https://nextjs.org)._
Enable `transpilePackages` for the UI CSS and components to be transpiled correctly.
```ts// next.config.tsconst nextConfig = { // Learn more here - https://nextjs.org/docs/advanced-features/compiler#module-transpilation // Required for UI css to be transpiled correctly 👇 transpilePackages: ['jotai-devtools'],}module.exports = nextConfig```
### Available props
```tstype DevToolsProps = { // defaults to false isInitialOpen?: boolean // pass a custom store store?: Store // Defaults to light theme?: 'dark' | 'light' // Set the position of the trigger button // Defaults to `bottom-left` position?: 'top-right' | 'top-left' | 'bottom-right' | 'bottom-left' // Custom nonce to allowlist jotai-devtools specific inline styles via CSP nonce?: string options?: { // Private atoms are used internally in atom creators like `atomWithStorage` // or `atomWithLocation`, etc. to manage the internal state. // Defaults to `false` shouldShowPrivateAtoms?: boolean // Expands the JSON tree view on initial render on Atom Viewer tab, Timeline tab, etc. // Defaults to `false` shouldExpandJsonTreeViewInitially?: boolean // The interval (in milliseconds) between each step of the time travel playback. // Defaults to `750ms` timeTravelPlaybackInterval?: number // The maximum number of snapshots to keep in the history. // The higher the number the more memory it will consume. // Defaults to `Infinity`. Recommended: `~30` snapshotHistoryLimit?: number }}```
### Usage
#### Provider-less
```tsximport { DevTools } from 'jotai-devtools'
const App = () => { return ( <> <DevTools /> {/* your app */} </> )}```
#### With Provider
```tsximport { createStore } from 'jotai'import { DevTools } from 'jotai-devtools'
const customStore = createStore()
const App = () => { return ( <Provider store={customStore}> <DevTools store={customStore} /> {/* your app */} </Provider> )}```
### Preview
<CodeSandbox id="k5p12d" />## useAtomsDebugValue
`useAtomsDebugValue` is a React hook that will show all atom values in React Devtools.
```tsfunction useAtomsDebugValue(options?: { store?: Store enabled?: boolean}): void```
Internally, it uses `useDebugValue` which is only effective in DEV mode.It will catch all atoms that are accessible from the place the hook is located.
### Example
```jsximport { useAtomsDebugValue } from 'jotai-devtools'
const textAtom = atom('hello')textAtom.debugLabel = 'textAtom'
const lenAtom = atom((get) => get(textAtom).length)lenAtom.debugLabel = 'lenAtom'
const TextBox = () => { const [text, setText] = useAtom(textAtom) const [len] = useAtom(lenAtom) return ( <span> <input value={text} onChange={(e) => setText(e.target.value)} />({len}) </span> )}
const DebugAtoms = () => { useAtomsDebugValue() return null}
const App = () => ( <Provider> <DebugAtoms /> <TextBox /> </Provider>)```
<CodeSandbox id="vvp12f" />## useAtomDevtools
`useAtomDevtools` is a React hook that manages ReduxDevTools extension for a particular atom.
```tsfunction useAtomDevtools<Value>( anAtom: WritableAtom<Value, Value>, options?: { store?: Store name?: string enabled?: boolean },): void```
The `useAtomDevtools` hook accepts a generic type parameter (mirroring the type stored in the atom). Additionally, the hook accepts two invocation parameters, `anAtom` and `name`.`anAtom` is the atom that will be attached to the devtools instance. `name` is an optional parameter that defines the debug label for the devtools instance. If `name` is undefined, `atom.debugLabel` will be used instead.
### Example
```tsimport { useAtomDevtools } from 'jotai-devtools'
// The interface for the type stored in the atom.export interface Task { label: string complete: boolean}
// The atom to debug.export const tasksAtom = atom<Task[]>([])
// If the useAtomDevtools name parameter is undefined, this value will be used instead.tasksAtom.debugLabel = 'Tasks'
export const useTasksDevtools = () => { // The hook can be called simply by passing an atom for debugging. useAtomDevtools(tasksAtom) // Specify a custom type parameter useAtomDevtools<Task[]>(tasksAtom) // You can attach two devtools instances to the same atom and differentiate them with custom names. useAtomDevtools(tasksAtom, 'Tasks (Instance 1)') useAtomDevtools(tasksAtom, 'Tasks (Instance 2)')}```
## useAtomsDevtools
⚠️ Note: This hook is experimental (feedbacks are welcome) and only works in a `process.env.NODE_ENV !== 'production'` environment.
`useAtomsDevtools` is a catch-all version of `useAtomDevtools` where it shows all atoms in the store instead of showing a specific one.
```tsfunction useAtomsDevtools( name: string, options?: { store?: Store enabled?: boolean },): void```
It takes a `name` parameter that is needed for naming the Redux devtools instance and a `store` parameter.
As a limitation for this API, we need to put `useAtomsDevtools` in a component where the consumed atoms should be in a lower place of the React tree than that component (`AtomsDevtools` in the below example).`AtomsDevtools` component can be considered as a best practice for our apps.
### Example
```jsxconst countAtom = atom(0);const doubleCountAtom = atom((get) => get(countAtom) * 2);
function Counter() { const [count, setCount] = useAtom(countAtom); const [doubleCount] = useAtom(doubleCountAtom); ...}
const AtomsDevtools = ({ children }) => { useAtomsDevtools('demo') return children}
export default function App() { return ( <AtomsDevtools> <Counter /> </AtomsDevtools> ) }```
<CodeSandbox id="3xobn" />## useAtomsSnapshot
⚠️ Note: This hook only works in a `process.env.NODE_ENV !== 'production'` environment. And it returns a static empty value in production.
`useAtomsSnapshot` takes a snapshot of the currently mounted atoms and their state.
```tsfunction useAtomsSnapshot(options?: { store?: Store }): AtomsSnapshot```
It accepts a `store` parameter and will return an `AtomsSnapshot`, which is basically a `Map<AnyAtom, unknown>`. You can use the `Map` API to iterate over atoms and their state.This hook is primarily meant for debugging and devtools use cases.
Be careful using this hook because it will cause the component to re-render for all state changes.
### Example
```jsximport { Provider } from 'jotai'import { useAtomsSnapshot } from 'jotai-devtools'
const RegisteredAtoms = () => { const atoms = useAtomsSnapshot() return ( <div> <p>Atom count: {atoms.size}</p> <div> {Array.from(atoms).map(([atom, atomValue]) => ( <p key={`${atom}`}>{`${atom.debugLabel}: ${atomValue}`}</p> ))} </div> </div> )}
const App = () => ( <Provider> <RegisteredAtoms /> </Provider>)```
## useGotoAtomsSnapshot
⚠️ Note: This hook only works in a `process.env.NODE_ENV !== 'production'` environment. And it works like an empty function in the production environment.
`useGotoAtomsSnapshot` will update the current Jotai state to match the passed snapshot.
```tsfunction useGotoAtomsSnapshot(options?: { store?: Store}): (values: Iterable<readonly [AnyAtom, unknown]>) => void```
This hook returns a callback, which takes a `snapshot` from the `useAtomsSnapshot` hook and will update the Jotai state. It accepts a `store` parameter.This hook is primarily meant for debugging and devtools use cases.
### Example
```jsximport { Provider } from 'jotai'import { useAtomsSnapshot, useGotoAtomsSnapshot } from 'jotai-devtools'
const petAtom = atom('cat')const colorAtom = atom('blue')
const UpdateSnapshot = () => { const snapshot = useAtomsSnapshot() const goToSnapshot = useGotoAtomsSnapshot() return ( <button onClick={() => { const newSnapshot = new Map(snapshot) newSnapshot.set(petAtom, 'dog') newSnapshot.set(colorAtom, 'green') goToSnapshot(newSnapshot) }} > Go to snapshot </button> )}```