无法通过ByBit统一v3 API订阅反向合约WebSocket数据

问题回顾 #

• 已通过/derivatives/v3/public/instruments-info接口确认BTCUSD为InversePerpetual（反向永续合约），状态正常可交易，合约详情如下：

{
  "symbol": "BTCUSD",
  "contractType": "InversePerpetual",
  "status": "Trading",
  "baseCoin": "BTC",
  "quoteCoin": "USD",
  "launchTime": "0",
  "deliveryTime": "0",
  "deliveryFeeRate": "",
  "priceScale": "2",
  "leverageFilter": {
    "minLeverage": "1",
    "maxLeverage": "100",
    "leverageStep": "0.01"
  },
  "priceFilter": {
    "minPrice": "0.50",
    "maxPrice": "999999.00",
    "tickSize": "0.50"
  },
  "lotSizeFilter": {
    "maxTradingQty": "1000000",
    "minTradingQty": "1",
    "qtyStep": "1"
  }
}

• 使用USDT本位合约WebSocket端点wss://stream.bybit.com/contract/usdt/public/v3订阅主题orderbook.25.BTCUSD时，收到报错：

{"success":false,"ret_msg":"error:handler not found,topic:orderbook.25.BTCUSD","conn_id":"027f109e-a7fb-4af0-8b69-78bbb293e34b","req_id":"","op":"subscribe"}

• 订阅USDT本位合约主题orderbook.25.BTCUSDT可正常成功，但尝试usd/public/v3、unified/public/v3端点未生效。

原因分析 #

ByBit衍生品V3 API将合约分为USDT本位和**USD本位（反向）**两类，对应不同的WebSocket端点，且订阅请求需严格遵循格式要求：

• USDT本位合约对应端点：wss://stream.bybit.com/contract/usdt/public/v3
• USD本位反向合约对应端点：wss://stream.bybit.com/contract/usd/public/v3

你尝试usd/public/v3端点未成功，大概率是订阅消息格式有误，而非端点本身错误。

正确操作步骤 #

1. 连接USD本位WebSocket公开端点：

wss://stream.bybit.com/contract/usd/public/v3

2. 发送符合格式的订阅请求（需保证args为数组格式）：

{"op": "subscribe", "args": ["orderbook.25.BTCUSD"]}

验证说明 #

发送上述请求后，若订阅成功，会收到如下格式的确认消息：

{"success":true,"ret_msg":"","conn_id":"xxx","req_id":"","op":"subscribe"}

随后即可接收BTCUSD反向永续合约的25档订单簿实时数据。

内容的提问来源于stack exchange，提问作者Xiang Zhang