WebSocket API Overview

​

Purpose

• Monitor order lifecycle events in real-time (creation, fills, cancellations)
• Track order state changes like balance and allowance updates
• Receive instant notifications when order status changes
• Access active orders through RPC methods
• Implement custom WebSocket providers for specialized use cases

​

When to Use WebSocket vs REST

​

Use WebSocket API when:

• You need real-time updates on order status changes
• You want to monitor multiple orders simultaneously
• You’re building interactive UIs that require instant feedback
• You need to react immediately to order fills or cancellations
• You want to reduce polling overhead for order status checks

​

Use REST API when:

• You need to fetch historical data or one-time queries
• You’re performing administrative operations like creating quotes
• You want simpler implementation for basic use cases
• You need stateless interactions without persistent connections

​

Real-time Order Monitoring

import { WebSocketApi } from '@1inch/cross-chain-sdk'

const wsSdk = new WebSocketApi({
  url: 'wss://api.1inch.com/fusion-plus/ws',
  authKey: 'your-auth-key'
})

// Monitor all order events
wsSdk.order.onOrder((data) => {
  console.log('received order event', data)
})

​

Key Capabilities

​

Architecture

• Base API (WebSocketApi) - Core connection management and low-level event handling
• Order namespace (order.*) - Order-specific event subscriptions
• RPC namespace (rpc.*) - Request/response methods for querying data

const ws = new WebSocketApi({ url: 'wss://api.1inch.com/fusion-plus/ws' })

// Base methods
ws.onOpen(() => console.log('Connected'))
ws.onError((error) => console.error('Error:', error))

// Order events
ws.order.onOrderCreated((data) => { /* handle creation */ })
ws.order.onOrderFilled((data) => { /* handle fill */ })

// RPC methods
ws.rpc.getActiveOrders()
ws.rpc.onGetActiveOrders((orders) => console.log(orders))

​

Next Steps