JotaiX

Migrating from v1 to v2

JotaiX is a custom extension of Jotai, a primitive and flexible state management library for React. Jotai offers a minimalistic API to manage global, derived, or async states in React, solving common issues such as unnecessary re-renders or complex context management. JotaiX builds upon this foundation, providing enhanced utilities and patterns for more efficient and streamlined state management in larger and more complex applications.

jotai-x, built on top of jotai, is providing a powerful store factory which solves these challenges, so you can focus on your app.

yarn add jotai jotai-x

For further details and API documentation, visit jotai-x.udecode.dev.

Why Choose jotai-x?

• Reduces boilerplate: Simplifies state management with concise and powerful utilities.
• Enhanced modular state management: Offers advanced features like atom stores, hydration utilities, and more.
• Improved developer experience: Strong TypeScript support ensures type safety and better developer tooling.
• Seamless integration with Jotai: Builds on top of Jotai's API, making it easy for existing Jotai users to adopt.

Core Features

Creating a Store

JotaiX allows for the creation of structured stores with ease, integrating seamlessly with Jotai's atom concept.

import { createAtomStore } from 'jotai-x';

// Notice how it uses the name of the store in the returned object.
export const { useElementStore, ElementProvider } = createAtomStore({ 
  element: null
}, { 
  name: 'element'
});

The createAtomStore function simplifies the process of creating and managing atom-based states.

Function Signature

createAtomStore<T extends object>(initialState: T, options?: CreateAtomStoreOptions): AtomStoreApi;

• initialState: This is an object representing the initial state of your store. Each key-value pair in this object is used to create an individual atom. This is required even if you want to set the initial value from the provider, otherwise the atom would not be created.
• options: Optional. This parameter allows you to pass additional configuration options for the store creation.

Options

The options object can include several properties to customize the behavior of your store:

• name: A string representing the name of the store, which can be helpful for debugging or when working with multiple stores.
• delay: If you need to introduce a delay in state updates, you can specify it here. Optional.
• effect: A React component that can be used to run effects inside the provider. Optional.
• extend: Extend the store with derived atoms based on the store state. Optional.

Return Value

The createAtomStore function returns an object (AtomStoreApi) containing the following properties and methods for interacting with the store:

• use<Name>Store:
  • A function that returns the following objects: useValue, useSet, useState, where values are hooks for each state defined in the store, and get, set, subscribe, store, where values are direct get/set accessors to modify each state.
  • useValue: Hooks for accessing a state within a component, ensuring re-rendering when the state changes. See useAtomValue.

      const store = useElementStore();
      const element = store.useElementValue();
      // alternative
      const element = useElementStore().useValue('element');

  • useSet: Hooks for setting a state within a component. See useSetAtom.

      const store = useElementStore();
      const element = store.useSetElement();
      // alternative
      const element = useElementStore().useSet('element');

  • useState: Hooks for accessing and setting a state within a component, ensuring re-rendering when the state changes. See useAtom.

      const store = useElementStore();
      const element = store.useElementState();
      // alternative
      const element = useElementStore().useState('element');

  • get: Directly get the state. Not a hook so it could be used in event handlers or other hooks, and the component won't re-render if the state changes. See createStore

      const store = useElementStore();
      useEffect(() => { console.log(store.getElement()) }, []);
      // alternative
      useEffect(() => { console.log(store.get('element')) }, []);

  • set: Directly set the state. Not a hook so it could be used in event handlers or other hooks. See createStore

      const store = useElementStore();
      useEffect(() => { store.setElement('div') }, []);
      // alternative
      useEffect(() => { store.set('element', 'div') }, []);

  • subscribe: Subscribe to the state change. . See createStore
    • NOTE: The subscribed callback will fire whenever the atom state or dependent atom states change. There is no equality check.

      const store = useElementStore();
      useEffect(() => store.subscribeElement((newElement) => console.log(newElement)), []);
      // alternative
      useEffect(() => store.subscribe('element', (newElement) => console.log(newElement)), []);

  • store: The JotaiStore for the current context.

      const store = useElementStore();
      const jotaiStore = store.store;

• <Name>Provider:
  • The API includes dynamically generated provider components for each defined store. This allows scoped state management within your application. More information in the next section.
• <name>Store:
  • atom: Access the atoms used by the store, including derived atoms defined using extend. See atom.

Provider-Based Store Hydration and Synchronization

createAtomStore generates a provider component (<Name>Provider) for a Jotai store. This provider not only supplies the store to its child components but also handles hydrating and syncing the store's state. Here's how it works:

• Hydration: Hydrates atoms with initial values. It's particularly useful for SSR, ensuring that the client-side state aligns with what was rendered on the server. Use initialValues prop.
• Synchronization: Updates atoms with new values as external changes occur, maintaining consistency across the application. Use <state> props: there is one for each state defined in the store.

Scoped Providers and Context Management

JotaiX creates scoped providers, enabling more granular control over different segments of state within your application. createAtomStore sets up a context for each store, which can be scoped using the scope prop. This is particularly beneficial in complex applications where nested providers are needed.

Derived Atoms

There are two ways of creating derived atoms from your JotaiX store.

Derived Atoms Using extend

Atoms defined using the extend option are made available in the same places as other values in the store.

const { useUserStore } = createAtomStore({
  username: 'Alice',
}, {
  name: 'user',
  extend: (atoms) => ({
    intro: atom((get) => `My name is ${get(atoms.username)}`),
  }),
});

const userStore = useUserStore();
const intro = userStore.useIntroValue();

Externally Defined Derived Atoms

Derived atoms can also be defined externally by accessing the store's atoms through the <name>Store API. Externally defined atoms can be accessed through the store using special hooks: useAtomValue, useSetAtom, useAtomState, getAtom, setAtom, subscribeAtom.

const { userStore, useUserStore } = createAtomStore({
  username: 'Alice',
}, { name: 'user' });

const introAtom = atom((get) => `My name is ${get(userStore.atom.username)}`);

const userStore = useUserStore();
const intro = userStore.useAtomValue(introAtom);

Example Usage

1. Create a store

import { createAtomStore } from 'jotai-x';

export type AppStore = {
  name: string;
  onUpdateName: (name: string) => void;
};

const initialState: Nullable<AppStore> = {
  name: null,
  onUpdateName: null,
};

export const { useAppStore, AppProvider } = createAtomStore(
  initialState as AppStore,
  { name: 'app' }
);

2. Use the store in a component

// ...

const App = () => {
  return (
    <AppProvider 
      initialValues={{
        onUpdateName: (name: string) => console.log(name)
      }}
      // Either here or in initialValues
      name="John Doe"
    >
      <Component />
    </AppProvider>
  );
};

const Component = () => {
  const appStore = useAppStore();
  const [name, setName] = store.useNameState();
  const onUpdateName = store.useOnUpdateNameValue();

  useEffect(() => store.subscribe.name((newName) => {
    console.log(`Name updated to: ${newName}`);
    // An alternative to `appStore.useNameState()`, won't rerender when the state changes
    assert.ok(newName === appStore.getName());
    if (newName.includes('#')) {
      // Equivalent to `appStore.useSetName()`'s return
      appStore.setName('invalid');
      onUpdateName('invalid');
    }
  }), [appStore])
  
  return (
    <div>
      <input value={name} onChange={(e) => setName(e.target.value)} />
      <button onClick={() => onUpdateName(name)}>Update</button>
    </div>
  );
};

Scoped Providers

const App = () => {
  return (
    // Parent scope
    <AppProvider 
      scope="parent"
      initialValues={{
        onUpdateName: (name: string) => console.log("Parent:", name)
      }}
      name="Parent User"
    >
      <div>
        <h1>Parent Component</h1>
        <Component />
        {/* Child scope */}
        <AppProvider 
          scope="child"
          initialValues={{
            onUpdateName: (name: string) => console.log("Child:", name)
          }}
          name="Child User"
        >
          <div>
            <h2>Child Component</h2>
            <Component />
          </div>
        </AppProvider>
      </div>
    </AppProvider>
  );
};

// Accessing state from the specified scope.
const Component = () => {
  // Here, we get the state from the parent scope
  const parentAppStore = useAppStore('parent');
  const [name, setName] = parentScope.useNameState();
  // Here, we get the state from the closest scope (default)
  const appStore = useAppStore();
  const onUpdateName = appStore.useOnUpdateNameValue();

  return (
    <div>
      <input value={name || ''} onChange={(e) => setName(e.target.value)} />
      <button onClick={() => onUpdateName(name)}>Update Name</button>
    </div>
  );
};

Migrate from v1 to v2

1. Return of use<Name>Store: get is renamed to use<Key>Value, set is renamed to useSet<Key>, use is renamed to useState.

- const name = useAppStore().get.name();
- const setName = useAppStore().set.name();
- const [name, setName] = useAppStore().use.name();

+ const appStore = useAppStore();
+ const name = appStore.useNameValue();
+ const setName = appStore.useSetName();
+ const [name, setName] = appStore.useNameState();

+ // alternative
+ const name = appStore.useValue('name');
+ const setName = appStore.useSet('name');
+ const [name, setName] = appStore.useState('name');

2. Rename .atom() APIs:

- const atomValue = useAppStore().get.atom(atomConfig);
- const setAtomValue = useAppStore().set.atom(atomConfig);
- const [atomValue, setAtomValue] = useAppStore().use.atom(atomConfig);

+ const appStore = useAppStore();
+ const atomValue = appStore.useAtomValue(atomConfig);
+ const setAtomValue = appStore.useSetAtom(atomConfig);
+ const [atomValue, setAtomValue] = appStore.useAtomState(atomConfig);

NOTE: Try to avoid using the key "atom" as the store state key because

1. useValue('atom') and useSet('atom') and useState('atom') are not supported. They are only valid if the key "atom" is presented in the store.

2. On the other hand, useAtomValue(), useSetAtom(), and useAtomState() cannot access the state if the key "atom" is presented in the store.

3. Return of use<Name>Store: store is no longer a function. Now it is a direct property.

- const store = useAppStore().store();

+ const appStore = useAppStore();
+ const jotaiStore = appStore.store;

4. Return of use<Name>Store: option is no longer a valid parameter of useValue and useSet. To control the behavior, directly pass the options to createAtomStore or use<Name>Store.

- const scope1Name = useAppStore().useValue.name(scope1Options);
- const scope2Name = useAppStore().useValue.name(scope2Options);

+ const scope1AppStore = useAppStore(scope1Options);
+ const scope1Name = scope1AppStore.useNameValue();
+ const scope2AppStore = useAppStore(scope2Options);
+ const scope2Name = scope2AppStore.useNameValue();

Contributing

Ideas and discussions

Discussions is the best place for bringing opinions and contributions. Letting us know if we're going in the right or wrong direction is great feedback and will be much appreciated!

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Contributors

🌟 Stars and 📥 Pull requests are welcome! Don't hesitate to share your feedback here. Read our contributing guide to get started.

License

MIT