react-state-forge

A lightweight and modular state management library for React applications, designed to handle various state scenarios such as basic, asynchronous, loadable, and controllable states. With support for nested states and seamless integration with React Suspense, this library ensures efficient state management by minimizing unnecessary rerenders.

This library covers a broad range of state needs, from simple value storage to asynchronous data management and polling-based controls:

Loadable State: Suitable for on-demand data fetching (e.g., API requests).
Controllable Loadable State: Ideal for managing polling, WebSocket connections, or Server-Sent Events (SSE), giving you the ability to pause, resume, or reset the loading process.

Whether you need simple state handling, asynchronous logic, or precise control over complex loading flows, this library provides the flexibility to fit your needs.

Installation

using npm:

npm install --save react-state-forge

or yarn:

yarn add react-state-forge

or pnpm:

pnpm add react-state-forge

API

createState / createNestedState
createAsyncState / createAsyncNestedState
createRequestableState / createRequestableNestedState
createPollableState / createPollableNestedState

	State	AsyncState	LoadableState	ControllableLoadableState
getValue	✅	✅	✅	✅
setValue	✅	✅	✅	✅
onValueChange	✅	✅	✅	✅
useValue / Controller	✅	✅	✅	✅
useMappedValue / MappedController	✅	✅	✅	✅
useMergedValue / MergedController	✅	✅	✅	✅
use / SuspenseController	❌	✅	✅	✅
useAll / SuspenseAllController	❌	✅	✅	✅
getPromise	❌	✅	✅	✅
onSlowLoading	❌	✅	✅	✅
awaitOnly / SuspenseOnlyController / SuspenseOnlyAllController	❌	✅	✅	✅
.error	❌	✅	✅	✅
.isLoaded	❌	✅	✅	✅
.load	❌	❌	✅	✅
withoutLoading	❌	❌	✅	✅
.loading.pause	❌	❌	❌	✅
.loading.resume	❌	❌	❌	✅
.loading.reset	❌	❌	❌	✅

createStateStorage
createPaginatedStorage / Pagination
Suspense
wrapErrorBoundary
bachedUpdates
SKELETON_STATE

createState

createState<T>(): State<T | undefined>;

createState<T>(initialValue: T): State<T>;

createState<T>(getInitialValue: () => T): State<T>;

Creates a basic state with an initial value.

import createState from 'react-state-forge/createState';
import useValue from 'react-state-forge/useValue';
import setValue from 'react-state-forge/setValue';

const togglerState = createState(false);

const Togglers = () => (
  <div>
    <button
      onClick={() => {
        setValue(togglerState, true);
      }}
    >
      turn on
    </button>
    <button
      onClick={() => {
        setValue(togglerState, false);
      }}
    >
      turn off
    </button>
    <button
      onClick={() => {
        setValue(togglerState, (prevValue) => !prevValue);
      }}
    >
      switch
    </button>
  </div>
);

const Light = () => {
  const value = useValue(togglerState);

  return <div>light {value ? 'on' : 'off'}</div>;
};

const Component = () => (
  <div>
    <div>
      <Light />
    </div>
    <div>
      <Togglers />
    </div>
  </div>
);

createNestedState

createNestedState<T>(): NestedState<T | undefined>;

createNestedState<T>(initialValue: T): NestedState<T>;

createNestedState<T>(getInitialValue: () => T): NestedState<T>;

Creates a nested state, where individual parts behave independently, triggering updates only when specific parts change. It allows for more efficient reactivity in complex data structures by minimizing unnecessary rerenders.

import createNestedState from 'react-state-forge/createNestedState';
import useValue from 'react-state-forge/useValue';
import setValue from 'react-state-forge/setValue';

const userState = createNestedState({
  profile: { name: 'Alice', age: 25 },
});

const Name = () => {
  const nameState = userState.scope().profile.name.end$;

  const name = useValue(nameState);

  return (
    <input
      value={name}
      onChange={(e) => {
        setValue(nameState, e.target.value);
      }}
    />
  );
};

const Age = () => {
  const ageState = userState.scope().profile.age.end$;

  const age = useValue(ageState);

  return (
    <input
      value={age}
      type='number'
      onChange={(e) => {
        setValue(ageState, +e.target.value);
      }}
    />
  );
};

const Component = () => (
  <div>
    <div>
      <Name />
    </div>
    <div>
      <Age />
    </div>
  </div>
);

createAsyncState

Creates a state with varying levels of capabilities based on the provided options:

AsyncState
```
createAsyncState<T, E = any>(
  options?: AsyncStateOptions<T>
): AsyncState<T, E>;

type AsyncStateOptions<T> = {
  value?: T | (() => T);
  isLoaded?(value: T, prevValue: T | undefined, attempt: number): boolean;
};
```
represents a state that supports asynchronous operations. It extends a regular state by introducing the following additional internal states:
- .error: A state that holds the latest error, if one occurred during loading.
- .isLoaded: A state that indicates whether the state has successfully loaded.

LoadableState

createAsyncState<T, E = any>(
  options: LoadableStateOptions<T, E>
): LoadableState<T, E>;

type LoadableStateOptions<T, E = any> = AsyncStateOptions<T> & {
  load(this: AsyncState<T, E>): void | (() => void);
  loadingTimeout?: number;
  reloadIfStale?: number;
  reloadOnFocus?: number;
};

Extends AsyncState with additional loading functionality, allowing the state to be loaded or reloaded.

ControllableLoadableState

Extends LoadableState with additional control over the loading process, including pause, resume, and reset.

createAsyncState<T, E = any>(
  options: ControllableLoadableStateOptions<T, E>
): ControllableLoadableState<T, E>;

type ControllableLoadableStateOptions<T, E = any> = LoadableStateOptions<
  T,
  E
> & {
  pause(): void;
  resume(): void;
  reset(): void;
};