WebSocket Endpoints

The Nord API provides WebSocket connections for real-time data streaming.

Base URLs

Environment	URL
Mainnet	`wss://zo-mainnet.n1.xyz`
Devnet	`wss://zo-devnet.n1.xyz`

Candle Data Stream

Stream real-time candlestick (OHLCV) data for charting.

Endpoint


wss://{host}/ws/candle@{symbol}:{resolution}

Parameters:

Name	Type	Description
`symbol`	string	Trading pair (e.g., “BTCUSD”, “ETHUSD”)
`resolution`	string	Timeframe: “1”, “5”, “15”, “60”, “240”, “1D”

Message Format


{
  "res": "1",
  "mid": 0,
  "t": 1705312800,
  "o": 97500.0,
  "h": 97550.0,
  "l": 97480.0,
  "c": 97520.0,
  "v": 125.5
}

Fields:

Field	Type	Description
`res`	string	Resolution/timeframe
`mid`	number	Market ID
`t`	number	Candle timestamp (Unix seconds)
`o`	number	Open price
`h`	number	High price
`l`	number	Low price
`c`	number	Close price
`v`	number	Volume (optional)

Example: JavaScript


const ws = new WebSocket("wss://zo-mainnet.n1.xyz/ws/candle@BTCUSD:1");
 
ws.onopen = () => {
  console.log("Connected to BTCUSD 1m candles");
};
 
ws.onmessage = (event) => {
  const candle = JSON.parse(event.data);
  console.log(`${new Date(candle.t * 1000).toLocaleTimeString()} | O: ${candle.o} H: ${candle.h} L: ${candle.l} C: ${candle.c}`);
};
 
ws.onclose = () => {
  console.log("Connection closed");
};

Example: Python


import asyncio
import websockets
import json
 
async def stream_candles():
    uri = "wss://zo-mainnet.n1.xyz/ws/candle@BTCUSD:1"
    
    async with websockets.connect(uri) as ws:
        print("Connected to BTCUSD 1m candles")
        
        async for message in ws:
            candle = json.loads(message)
            print(f"O: {candle['o']:.1f} H: {candle['h']:.1f} L: {candle['l']:.1f} C: {candle['c']:.1f}")
 
asyncio.run(stream_candles())

Connection Best Practices

Reconnection: Implement automatic reconnection with exponential backoff
Heartbeat: The server may send periodic pings; respond with pongs to keep the connection alive
Single connection per stream: Each WebSocket connection handles one symbol/resolution pair
Resource cleanup: Close connections when switching symbols or when the component unmounts

Example: Reconnecting Client


import asyncio
import websockets
import json
 
async def resilient_stream(symbol: str, resolution: str):
    uri = f"wss://zo-mainnet.n1.xyz/ws/candle@{symbol}:{resolution}"
    retry_delay = 1
    
    while True:
        try:
            async with websockets.connect(uri) as ws:
                print(f"Connected to {symbol} {resolution} stream")
                retry_delay = 1  # Reset on successful connection
                
                async for message in ws:
                    candle = json.loads(message)
                    yield candle
                    
        except websockets.ConnectionClosed:
            print(f"Connection closed, reconnecting in {retry_delay}s...")
            await asyncio.sleep(retry_delay)
            retry_delay = min(retry_delay * 2, 30)  # Max 30s delay
 
async def main():
    async for candle in resilient_stream("BTCUSD", "1"):
        print(f"Price: ${candle['c']:,.1f}")
 
asyncio.run(main())