@syeedalireza/bid-stream

A high-performance WebSocket/Redis adapter optimized for broadcasting "lowest bid" updates in real-time reverse auctions.

Features

• Redis Pub/Sub: Leverages Redis for scalable, distributed message broadcasting.
• Event Emitter: Simple Node.js EventEmitter interface for handling incoming bids.
• Auction-Specific Channels: Automatically routes bids to specific auction channels.
• TypeScript Support: Fully typed with TypeScript.

Installation

npm install @syeedalireza/bid-stream ioredis

Usage

import { BidStream } from '@syeedalireza/bid-stream';

// Initialize the stream
const stream = new BidStream({
  redisUrl: 'redis://localhost:6379',
  channelPrefix: 'auction:', // Optional, defaults to 'auction:'
});

// Subscribe to a specific auction
await stream.subscribeToAuction('auction-123');

// Listen for all bids
stream.on('bid', (bid) => {
  console.log('Received bid:', bid);
});

// Listen for bids on a specific auction
stream.on('bid:auction-123', (bid) => {
  console.log('Received bid for auction-123:', bid);
});

// Broadcast a new bid
await stream.broadcastBid({
  auctionId: 'auction-123',
  bidId: 'bid-1',
  bidderId: 'user-1',
  amount: 100,
  timestamp: Date.now(),
});

// Cleanup when done
await stream.disconnect();

API

BidStream

Constructor

new BidStream(config: BidStreamConfig)

• config.redisUrl: Redis connection string.
• config.channelPrefix: Prefix for Redis channels (default: 'auction:').

Methods

• subscribeToAuction(auctionId: string): Promise<void>: Subscribes to updates for a specific auction.
• unsubscribeFromAuction(auctionId: string): Promise<void>: Unsubscribes from an auction.
• broadcastBid(bid: BidMessage): Promise<void>: Broadcasts a bid to all subscribers of that auction.
• disconnect(): Promise<void>: Closes Redis connections.

Events

• 'bid': Emitted for any received bid. Payload: BidMessage.
• 'bid:[auctionId]': Emitted for bids specific to auctionId. Payload: BidMessage.
• 'error': Emitted on JSON parsing errors or Redis errors. Payload: Error.