Pulsy , a simple react state management library

Here's a README for your Pulsy package:

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Pulsy

Pulsy is a lightweight, flexible state management library for React that supports persistence, middleware, memoization, and enhanced dev tools integration. This package enables you to easily create and manage state across your React application with advanced features like persistence to local storage and middleware to control state updates.

Features

• State Management: Manage global state across your application.
• Persistence: Automatically save and load states to/from localStorage.
• Middleware: Add custom logic to manipulate state updates.
• Dev Tools Integration: Built-in support for logging, time-travel debugging, and performance monitoring.
• Memoization: Optimize re-rendering by memoizing state values.

Installation

First, install the package using npm or yarn:

npm install pulsy

or

yarn add pulsy

Basic Usage

Pulsy allows you to create stores, use them in your components, and optionally configure persistence and middleware.

1. Initialize Pulsy

Before using Pulsy, configure the store with initializePulsy. You can define multiple stores at once and configure persistence or memoization.

import { initializePulsy } from 'pulsy';

// Initializing Pulsy with default values
initializePulsy({
  user: { name: 'John Doe', age: 30 },
  theme: 'light',
}, {
  enableDevTools: true,
  persist: true,
});

2. Create and Use a Store

After initialization, you can use the usePulsy hook in any React component to access and update the store.

import usePulsy from 'pulsy';

function UserProfile() {
  const [user, setUser] = usePulsy('user');

  const updateUser = () => {
    setUser(prev => ({ ...prev, age: prev.age + 1 }));
  };

  return (
    <div>
      <h1>{user.name}</h1>
      <p>Age: {user.age}</p>
      <button onClick={updateUser}>Increase Age</button>
    </div>
  );
}

export default UserProfile;

In this example:

• usePulsy('user') retrieves the current user store value and provides a setter function to update it.
• The updateUser function increments the user's age, demonstrating how to update the state.

3. Persist State

By enabling persistence, Pulsy automatically saves the store to localStorage. It also retrieves the value from localStorage when the component mounts.

To persist a specific store during its creation, use the persist option:

initializePulsy({
  user: { name: 'John Doe', age: 30 },
  theme: 'light',
}, {
  persist: true, // Enable persistence globally
});

Pulsy will save the store state in localStorage under the key pulsy_{storeName}.

4. Middleware

You can add middleware to modify the store's value before it is set. For example, to log changes or restrict certain values:

import { addMiddleware } from 'pulsy';

// Middleware that ensures age cannot be set below 0
addMiddleware('user', (newValue, prevValue) => {
  return { ...newValue, age: Math.max(newValue.age, 0) };
});

In this example:

• The middleware checks if the new age is below 0 and ensures it cannot be negative.

5. Namespaced Stores

You can create namespaced stores for better organization, especially when dealing with complex state structures:

import { createNamespacedStore } from 'pulsy';

const useUserStore = createNamespacedStore('user');

function UserSettings() {
  const [userSettings, setUserSettings] = useUserStore('settings');
  return <div>{JSON.stringify(userSettings)}</div>;
}

6. DevTools

Pulsy integrates with your app's development tools. By enabling enableDevTools, Pulsy logs every store creation, update, and error to help with debugging:

initializePulsy({
  user: { name: 'Jane Doe', age: 28 },
}, { enableDevTools: true });

API

initializePulsy(storeConfigs, config?)

Initializes Pulsy with a set of stores and optional global configurations.

• storeConfigs: An object defining the stores and their initial values.
• config: Optional. A PulsyConfig object to customize global settings.

type PulsyConfig = {
  enableDevTools?: boolean; // Enable dev tools logging
  onStoreCreate?: (name: string, initialValue: any) => void; // Callback on store creation
  onStoreUpdate?: (name: string, newValue: any) => void; // Callback on store update
  persist?: boolean; // Enable persistence
  defaultMemoize?: boolean; // Enable memoization
};

usePulsy(name)

The main hook to retrieve and update a store.

usePulsy<T>(name: string): [T, (newValue: T | (prevValue: T) => T) => Promise<void>];

• name: The name of the store.
• Returns a tuple: [storeValue, setStoreValue].

createStore(name, initialValue, options?)

Creates a new store manually.

• name: The name of the store.
• initialValue: The initial value of the store.
• options: Optional configuration for persistence, middleware, or memoization.

setStoreValue(name, value)

Sets the value of a store.

• name: The store name.
• value: The new value for the store.

addMiddleware(name, middleware)

Adds middleware to an existing store.

• name: The store name.
• middleware: A function to modify the store value during updates.

clearPersistedStores()

Clears all persisted store values from localStorage.

clearPersistedStores();

Advanced Features

Memoization

You can enable memoization on a store to avoid unnecessary renders when the value doesn't change.

initializePulsy({
  user: { name: 'Jane Doe', age: 28 },
}, { defaultMemoize: true });

Time-Travel

Pulsy supports time-travel debugging, allowing you to step back and forth through store updates. This can be configured with devTools.

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License

This package is released under the MIT License.

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This README covers basic installation, usage, and advanced features of Pulsy. You can add more advanced examples or custom configurations as your package evolves!