{
  "id": -1,
  "method": "private/broker/broker-access-token-created",
  "code": "0",
  "detail_code": "0",
  "result": {
    "broker_reference_id": "cdc-authorization-1234567890123",
    "broker_access_token": "78164676-f5f0-43d0-8e7a-e0a3244bd4d9"
  }
}

curl -l [callback] -H 'content-type: application/json' -d '{"id": -1,"method": "private/broker/broker-access-token-created","code": "0","detail_code": "0","result": {"broker_reference_id": "[brokerReferenceId]","broker_access_token": "[accessToken]"    }}'

const crypto = require("crypto-js");

const signRequest = (request_body, api_key, secret) => {
  const { id, method, params, nonce } = request_body;

  function isObject(obj) { return obj !== undefined && obj !== null && obj.constructor == Object; }
  function isArray(obj) { return obj !== undefined && obj !== null && obj.constructor == Array; }
  function arrayToString(obj) { return obj.reduce((a,b) => { return a + (isObject(b) ? objectToString(b) : (isArray(b) ? arrayToString(b) : b)); }, ""); }
  function objectToString(obj) { return (obj == null ? "" : Object.keys(obj).sort().reduce((a, b) => { return a + b + (isArray(obj[b]) ? arrayToString(obj[b]) : (isObject(obj[b]) ? objectToString(obj[b]) : obj[b])); }, "")); }

  const paramsString = objectToString(params);

  console.log(paramsString);

  const sigPayload = method + id + api_key + paramsString + nonce;
  request_body.sig = crypto.HmacSHA256(sigPayload, secret).toString(crypto.enc.Hex);
};

const apiKey = "token"; /* User API Key */
const apiSecret = "secretKey"; /* User API Secret */

let request = {
  id: 11,
  method: "private/get-order-detail",
  api_key: API_KEY,
  params: {
    order_id: 53287421324
  },
  nonce: 1587846358253,
};

const requestBody = JSON.stringify(signRequest(request, apiKey, apiSecret)));

import hmac
import hashlib
import time

API_KEY = "API_KEY"
SECRET_KEY = "SECRET_KEY"

req = {
    "id": 14,
    "method": "private/create-order-list",
    "api_key": API_KEY,
    "params": {
        "contingency_type": "LIST",
        "order_list": [
            {
                "instrument_name": "ONE_USDT",
                "side": "BUY",
                "type": "LIMIT",
                "price": "0.24",
                "quantity": "1.0"
            },
            {
                "instrument_name": "ONE_USDT",
                "side": "BUY",
                "type": "STOP_LIMIT",
                "price": "0.27",
                "quantity": "1.0",
                "trigger_price": "0.26"
            }
        ]
    },
    "nonce": int(time.time() * 1000)
}

# First ensure the params are alphabetically sorted by key
param_str = ""

MAX_LEVEL = 3


def params_to_str(obj, level):
    if level >= MAX_LEVEL:
        return str(obj)

    return_str = ""
    for key in sorted(obj):
        return_str += key
        if obj[key] is None:
            return_str += 'null'
        elif isinstance(obj[key], list):
            for subObj in obj[key]:
                return_str += params_to_str(subObj, ++level)
        else:
            return_str += str(obj[key])
    return return_str


if "params" in req:
    param_str = params_to_str(req['params'], 0)

payload_str = req['method'] + str(req['id']) + req['api_key'] + param_str + str(req['nonce'])

req['sig'] = hmac.new(
    bytes(str(SECRET_KEY), 'utf-8'),
    msg=bytes(payload_str, 'utf-8'),
    digestmod=hashlib.sha256
).hexdigest()

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using System.Net.WebSockets;

private const string API_KEY = "YOUR_API_KEY";
private const string API_SECRET = "YOUR_API_SECRET";

private static string GetSign (Dictionary Request)
{
    Dictionary Params = Request.Params;

    // Ensure the params are alphabetically sorted by key
    string ParamString = string.Join("", Params.Keys.OrderBy(key => key).Select(key => key + Params[key]));

    string SigPayload = Request.method + Request.id + API_KEY + ParamString + Request.nonce;

    var hash = new HMACSHA256(API_SECRET);
    var ComputedHash = hash.ComputeHash(SigPayload);
    return ToHex(ComputedHash, false);
}

import com.fasterxml.jackson.annotation.JsonProperty;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.util.Map;

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class ApiRequestJson {
  private Long id;
  private String method;
  private Map<String, Object> params;
  private String sig;

  @JsonProperty("api_key")
  private String apiKey;

  private Long nonce;
}

//------------

import java.math.BigDecimal;
import java.nio.charset.StandardCharsets;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.codec.binary.Hex;

public class SigningUtil {

  private static final String HMAC_SHA256 = "HmacSHA256";
  private static final int MAX_LEVEL = 3;

  public static boolean verifySignature(ApiRequestJson apiRequestJson, String secret) {
    try {
      return genSignature(apiRequestJson, secret).equalsIgnoreCase(apiRequestJson.getSig());
    } catch (Exception e) {
      return false;
    }
  }

  @SuppressWarnings("unchecked")
  public static String getParamString(final Object paramObject) {
    StringBuilder sb = new StringBuilder();
    appendParamString(sb, paramObject, 0);
    return sb.toString();
  }


  @SuppressWarnings("unchecked")
  private static void appendParamString(final StringBuilder paramsStringBuilder, final Object paramObject, final int level) {
    if (level >= MAX_LEVEL) {
      paramsStringBuilder.append(paramObject.toString());
      return;
    }

    if (paramObject instanceof Map) {
      TreeMap<String, Object> params = new TreeMap<>((Map) paramObject);
      for (Map.Entry<String, Object> entry : params.entrySet()) {
        if (entry.getValue() instanceof Double) {
          paramsStringBuilder
              .append(entry.getKey())
              .append((new BigDecimal(entry.getValue().toString()))
                  .stripTrailingZeros()
                  .toPlainString());
        } else if (entry.getValue() instanceof List || entry.getValue() instanceof Map) {
          paramsStringBuilder
              .append(entry.getKey());
          appendParamString(paramsStringBuilder, entry.getValue(), level + 1);
        } else {
          paramsStringBuilder
              .append(entry.getKey())
              .append(entry.getValue());
        }
      }
    } else if (paramObject instanceof List) {
      List list = (List) paramObject;
      for (Object o : list) {
        appendParamString(paramsStringBuilder, o, level + 1);
      }
    } else {
      paramsStringBuilder.append(paramObject.toString());
    }
  }

  public static String genSignature(ApiRequestJson apiRequestJson, String secret)
      throws NoSuchAlgorithmException, InvalidKeyException {
    final byte[] byteKey = secret.getBytes(StandardCharsets.UTF_8);
    Mac mac = Mac.getInstance(HMAC_SHA256);
    SecretKeySpec keySpec = new SecretKeySpec(byteKey, HMAC_SHA256);
    mac.init(keySpec);

    String paramsString = "";

    if (apiRequestJson.getParams() != null) {
      paramsString += getParamString(apiRequestJson.getParams());
    }

    String sigPayload =
        apiRequestJson.getMethod()
            + apiRequestJson.getId()
            + apiRequestJson.getApiKey()
            + paramsString
            + (apiRequestJson.getNonce() == null ? "" : apiRequestJson.getNonce());

    byte[] macData = mac.doFinal(sigPayload.getBytes(StandardCharsets.UTF_8));

    return Hex.encodeHexString(macData);
  }

  public static ApiRequestJson sign(ApiRequestJson apiRequestJson, String secret)
      throws InvalidKeyException, NoSuchAlgorithmException {
    apiRequestJson.setSig(genSignature(apiRequestJson, secret));

    return apiRequestJson;
  }

  public static void main(String[] argv) throws InvalidKeyException, NoSuchAlgorithmException {
    ApiRequestJson apiRequestJson = ApiRequestJson.builder()
            .id(11L)
            .apiKey("token")
            .method("public/auth")
            .nonce(1589594102779L)
            .build();

    System.out.println(genSignature(apiRequestJson, "secretKey"));

    System.out.println(sign(apiRequestJson, "secretKey"));

  }
}

{
  "id":"1",
  "method": "private/broker/create-fast-api-key",
  "params": {
    "broker_access_token":"dddd1234-cafe-deee-9399-123443210000",
    "broker_id":"00111234-cafe-deee-9399-123443210000",
    "broker_reference_id":"69991111-cafe-deee-9399-123443210000",
    "whitelist_ips":"8.8.8.8"
  },
  "nonce": 1680012321987
}

{
 "id": "11",
 "method": "private/broker/create-fast-api-key",
 "code": 0,
 "result": {
    "ts": 1683013329206,
    "api_key": "eUF7eDrkkM2jwfsnDqNATW",
    "secret_key": "Xcow878VrkH6dSSkiKQyMh",
    "enabled_trading": true,
    "enabled_withdrawal": false
  }
}

{
  "id": 1587523073344,
  "method": "public/heartbeat",
  "code": 0
}

{
  "id": 1587523073344,
  "method": "public/respond-heartbeat"
}