API request signing

1. KYC Data should be sent in the Request Body in JSON format.
2. Convert the Request Body JSON to a JSON String
3. Use the HmacSHA256 algorithm to sign the JSON String, and assign the result to the X-SHA2-Signature request header.

Sign the exact string you send. Serialize the JSON String compactly, with no extra whitespace, and send that same string as the request body. Re-serializing or reformatting the JSON after signing will invalidate the signature.

Examples

1. Request Body to be sent:

Code
{
  "bizEntityKey": "<your_biz_entity_key>",
  "entityCustomerId": "<your_user_id>",
  "kycType": "USER",
  "extra": {},
  "notifyUrl": "<your_notify_url>"
}

2. Converted Request BODY to JSON String:

Code
{
  "bizEntityKey": "<your_biz_entity_key>",
  "entityCustomerId": "<your_user_id>",
  "kycType": "USER",
  "extra": {},
  "notifyUrl": "<your_notify_url>"
}

3. Sign the JSON String (see below examples).

NodeJS Example

Code
const crypto = require("crypto");

const secret = "<your_secret_key>";
const postData = {
  bizEntityKey: "<your_biz_entity_key>", // entity key will be decided and given Binance team
  entityCustomerId: "<your_user_id>",
  kycType: "USER",
  extra: {},
  notifyUrl: "<your_notify_url>",
};
const hash = crypto.createHmac("sha256", secret).update(JSON.stringify(postData)).digest("hex");

Java Example

Code
import org.apache.commons.codec.binary.Hex;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;

public class App {
    public static void main(String[] args) throws Exception {

        String rawString = "{ \"bizEntityKey\": \"<your_biz_entity_key>\", \"entityCustomerId\": \"<your_user_id>\", \"kycType\": \"USER\", \"extra\": { }, \"notifyUrl\": \"<your_notify_url>\" }";
        Mac sha256Hmac = Mac.getInstance("HmacSHA256");
        SecretKeySpec secretKey = new SecretKeySpec("<your_secret_key>".getBytes(), "HmacSHA256");
        sha256Hmac.init(secretKey);
        String eventSignature = new String(Hex.encodeHex(sha256Hmac.doFinal(rawString.getBytes(StandardCharsets.UTF_8))));

        System.err.println(eventSignature);
    }
}

Python Example

Code
import requests
import json
import hmac
import hashlib

body = {
    "bizEntityKey": "<your_biz_entity_key>",
    "entityCustomerId": "<your_user_id>",
    "kycType": "USER",
    "extra": {
    },
    "notifyUrl": "<your_notify_url>"
}

api_secret = '<your_secret_key>' ##please replace with your own

json.dumps(body, separators=(',', ':')) #use this instead to remove extra spaces

signature = hmac.new(api_secret.encode(), json_str.encode(), hashlib.sha256).hexdigest()