@nolag/chat

Multi-room chat with presence, typing indicators, message replay, and user mapping.

Overview

@nolag/chat is a high-level SDK that turns any application into a fully-featured chat system. It handles room management, user presence, typing indicators, message history replay, and unread tracking, all on top of @nolag/js-sdk. You create a NoLagChat instance, connect, join rooms, and start sending messages within minutes.

Key Features

• Multi-room chat with isolated presence per room
• Typing indicators with automatic timeout
• Message replay to catch up on up to 7 days of history after reconnect
• User mapping to attach names, avatars, and metadata to each actor
• Unread message tracking with per-room badge counts
• Automatic reconnection with state restoration

How It Works

NoLagChat wraps the @nolag/js-sdk client and manages a lobby for global user presence. When you call joinRoom(), it returns a ChatRoom instance that subscribes to two topics: messages for durable chat history and _typing for ephemeral typing signals. A MessageStore inside each room accumulates messages and replayed history, while a PresenceManager tracks who is currently online.

Installation

npm install @nolag/chat @nolag/js-sdk

Quick Start

import { NoLagChat } from '@nolag/chat'

// Create and connect the client
const chat = new NoLagChat('your-access-token', {
  user: { id: 'user-123', name: 'Alice', avatar: '/img/alice.png' },
})

await chat.connect()

// Join a room
const room = await chat.joinRoom('general')

// Send a message
await room.sendMessage('Hello everyone!')

// Listen for messages
room.on('message', (msg) => {
  console.log(`[${msg.sender.name}]: ${msg.text}`)
  console.log('Sent at:', new Date(msg.timestamp))
})

// Listen for typing indicators
room.on('typing', ({ user, isTyping }) => {
  console.log(`${user.name} is ${isTyping ? 'typing...' : 'no longer typing'}`)
})

// Trigger typing events
room.startTyping()
// ... user stops typing
room.stopTyping()

// Get online users in this room
const users = room.getUsers()
console.log('Online:', users.length)

// Leave when done
await chat.leaveRoom('general')
chat.disconnect()

API Reference

NoLagChat

The main class. Manages the WebSocket connection, global user presence, and room lifecycle.

Events: NoLagChat

ChatRoom

Returned by joinRoom(). Scoped to a single room; handles messaging, typing, and per-room presence.

Events: ChatRoom