I'm using the following code to get the binance api signature, but it doesn't work!! can any one help!
int timeStamp = DateTime.now().millisecondsSinceEpoch;
String queryParams = 'timestamp=' + timeStamp.toString();
List<int> key = convert.utf8.encode(this.apiSecret);
crypto.Hmac hmac = new crypto.Hmac(crypto.sha256, key);
List<int> messageBytes = convert.utf8.encode(queryParams);
crypto.Digest digest = hmac.convert(messageBytes);
String signature = hex.encode(digest.bytes);
Update 16 Aug 2021
Binance has updated new Signature key format with SHA512 algorithm for more detail you can take a look at Binance api document.
String signature = timestamp.toString() + "\n" + nonce + "\n" + bytes +
"\n";
YOU MUST INCLUDE "\n"
My Code
I have try Signature key that print from this code on Binance payment api, everything work fine. (signature must be uppercase when you send request)
var key = utf8.encode('YOUR_SECRET_KEY'); // get from binance api
var timestamp = DateTime.now().millisecondsSinceEpoch;
var nonce = "asdopewrmweqjidsfnosd"; // Random 32 length String,
var bytes = '''{
"merchantId": "",
"subMerchantId": "",
"merchantTradeNo": "9825382937292117596",
"totalFee": 0.5,
"productDetail": "Greentea ice cream cone",
"currency": "USDT",
"returnUrl": "",
"tradeType": "WEB",
"productType": "Food",
"productName": "Ice Cream"
}''';
String payload = timestamp.toString() + "\n" + nonce + "\n" + bytes +
"\n";
var hmacSha512 = Hmac(sha512, key); // HMAC-SHA512/
var digest = hmacSha512.convert(utf8.encode(payload));
print(timestamp.toString() + "\n");
print("HMAC digest as hex string: ${digest.toString().toUpperCase()}");
You can use my new dart package: https://pub.dev/packages/binance_api_dart/versions/1.0.1 it is a http wrapper for binance api call. It is able to create the signature and return the http response.
