প্রমাণীকরণ API

import crypto from "crypto";

// 1. Generate Signature
function generateSignature(
  apiSecret: string,
  body: object,
  timestamp: number,
  nonce?: string
) {
  const payload = JSON.stringify(body) + timestamp + (nonce || "");
  return crypto.createHmac("sha256", apiSecret).update(payload).digest("hex");
}

// Client Usage Example
const apiKey = "client123";
const apiSecret = "mysecretkey";
const body = { /* Query Params or Body */ }; 
const timestamp = Date.now();
const nonce = crypto.randomBytes(8).toString("hex");

const signature = generateSignature(apiSecret, body, timestamp, nonce);

console.log({ apiKey, timestamp, nonce, signature });

// 2. Verify Signature
function verifySignature(
  apiSecret: string,
  body: object,
  timestamp: number,
  nonce: string,
  signature: string
) {
  const expected = generateSignature(apiSecret, body, timestamp, nonce);
  return expected === signature;
}

// Verification Result
const isValid = verifySignature(apiSecret, body, timestamp, nonce, signature);
console.log("Is Valid:", isValid);