MCard JS

A JavaScript implementation of MCard, a data model for persistently storing content with cryptographic hashing and timestamping.

Overview

MCard JS provides a cross-environment implementation that works in both Node.js and browser environments. The library offers functionality for:

• Creating and managing content cards with cryptographic hashing
• Storing structured data with timestamps
• Searching and retrieving cards by various criteria
• Synchronizing data with persistence providers
• Redux middleware for persisting application state

Key Components

Core

• MCard: Core data structure that wraps content with hash, timestamp, and metadata
• CardCollection: Manages multiple MCards, providing search and retrieval capabilities
• GTime: Handles global timestamping with region-aware formatting

Middleware

• mcardPersistenceMiddleware: Redux middleware for persisting actions and state snapshots

Utilities

• SafeBuffer: Cross-environment Buffer implementation for Node.js and browsers
• Content Type Detection: Automated detection and handling of various content types
• Cryptographic Utilities: Hash generation and validation

Cross-Environment Compatibility

MCard JS is designed to work in both Node.js and browser environments through:

• Buffer polyfills for browser compatibility
• Environment detection for optimal feature usage
• TextEncoder/TextDecoder polyfills

Recent Updates

Redux Middleware Improvements

• Enhanced middleware implementation following the Redux pattern (store => next => action)
• Support for both named and default exports for compatibility
• Graceful handling when storage service is unavailable
• Better test coverage (93.75% statements, 100% functions)

Buffer Compatibility Fixes

• Cross-environment support for Buffer/Uint8Array content handling
• Improved content access and conversion
• Robust test suite for both Node.js and browser environments

Getting Started

Installation

npm install @benkoo/mcard

Basic Usage

import { MCard, CardCollection } from '@benkoo/mcard';

// Create a card with content
const card = new MCard('Hello, World!');

// Create a collection and add the card
const collection = new CardCollection();
collection.add(card);

// Retrieve by hash
const retrievedCard = collection.get(card.hash);

// Search by content
const searchResults = collection.search_by_string('Hello');

Redux Integration

import { createStore, applyMiddleware } from 'redux';
import { mcardPersistenceMiddleware } from '@benkoo/mcard';
import McardStorageService from './mcardStorageService';
import rootReducer from './reducers';

const store = createStore(
  rootReducer,
  applyMiddleware(
    mcardPersistenceMiddleware(McardStorageService)
  )
);

Development

Testing

Run the test suite with:

npm test

Building

npm run build

License

MIT