ตัวอย่าง

ตัวอย่างการดึงยอดคงเหลือในภาษา PHP:

<?php
define('API_URL', 'https://api.example.com');
define('SECRET', 'secretkeysecretkeysecretkeysecretkeysecretkeysecretkey');
define('MERCHANT_ID', 'THXXXXXXXX');
define('TOKEN', 'tokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentoken');


$req = [
    "merchant_id" => MERCHANT_ID,
    "token" => TOKEN,
    "time" => time()
];

$post_data = json_encode($req);
$signature = hash_hmac("sha256", $post_data, SECRET);
$curl = curl_init(API_URL . "/balance");
$headers = [
  'Content-Type: application/json',
  'X-Signature: ' . $signature
];
curl_setopt($curl, CURLOPT_HTTPHEADER, $headers);
curl_setopt($curl, CURLOPT_POST, 1);
curl_setopt($curl, CURLOPT_POSTFIELDS, $post_data);
$response = curl_exec($curl);
curl_close($curl);
echo $response;

ตัวอย่างในภาษา Node.js

const axios = require('axios');
const crypto = require('crypto');

const API_URL = 'https://api.example.com';
const SECRET = 'secretkeysecretkeysecretkeysecretkeysecretkeysecretkey';
const MERCHANT_ID = 'THXXXXXXXX';
const TOKEN = 'tokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentokentoken';

const req = {
  merchant_id: MERCHANT_ID,
  token: TOKEN,
  time: Math.floor(Date.now() / 1000)
};

const postData = JSON.stringify(req);
const signature = crypto.createHmac('sha256', SECRET)
                    .update(postData)
                    .digest('hex');

const headers = {
  'Content-Type': 'application/json',
  'X-Signature': signature
};

axios.post(API_URL + '/balance', postData, { headers })
  .then(response => {
    console.log(response.data);
  })
  .catch(error => {
    console.error(error);
  });

ตัวอย่างในภาษา Java

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.nio.charset.StandardCharsets;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;


import java.util.HashMap;
import java.util.Map;

public class ApiClient {

    private static final String API_URL = "https://api.example.com/balance";
    private static final String SECRET = "xxxxxx";
    private static final String MERCHANT_ID = "TH00000000";
    private static final String TOKEN = "yyyyyyyyy";

    public static void main(String[] args) {
        try {
            // เตรียมข้อมูล request


            String postData = String.format(
                            "{\"merchant_id\":\"%s\",\"token\":\"%s\",\"time\":%d}",
                            MERCHANT_ID, TOKEN, System.currentTimeMillis() / 1000
                        );

            // สร้าง HMAC SHA-256 Signature
            String signature = generateSignature(postData, SECRET);

            // สร้าง HTTP request
            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(API_URL))
                    .header("Content-Type", "application/json")
                    .header("X-Signature", signature)
                    .POST(HttpRequest.BodyPublishers.ofString(postData))
                    .build();

            // ส่ง HTTP request
            HttpClient client = HttpClient.newHttpClient();
            HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());

            // จัดการ response
            System.out.println(response.body());

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // ฟังก์ชันสร้าง HMAC SHA-256 Signature
    private static String generateSignature(String data, String secret) throws Exception {
        Mac sha256Hmac = Mac.getInstance("HmacSHA256");
        SecretKeySpec secretKey = new SecretKeySpec(secret.getBytes(StandardCharsets.UTF_8), "HmacSHA256");
        sha256Hmac.init(secretKey);
        byte[] hash = sha256Hmac.doFinal(data.getBytes(StandardCharsets.UTF_8));
        return bytesToHex(hash);
    }

    // ฟังก์ชันช่วยแปลง byte array เป็น hex string
    private static String bytesToHex(byte[] bytes) {
        StringBuilder hexString = new StringBuilder(2 * bytes.length);
        for (byte b : bytes) {
            String hex = Integer.toHexString(0xff & b);
            if (hex.length() == 1) hexString.append('0');
            hexString.append(hex);
        }
        return hexString.toString();
    }
}

หากคุณใช้ Postman ในการทดสอบ API สามารถเพิ่มโค้ดนี้ใน Pre-Request Script ได้

var secret_key = 'YOUR_SECRET_KEY_HERE';
var signBytes = CryptoJS.HmacSHA256(pm.request.body.raw, secret_key);
var signHex = CryptoJS.enc.Hex.stringify(signBytes);
pm.request.headers.add({
    key: "X-Signature",
    value: signHex
});

ตัวอย่างในภาษา C#

using System;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using Newtonsoft.Json;
using System.Security.Cryptography;

public class ApiRequestExample
{
    private const string API_URL = "https://api.example.com/balance";
    private const string SECRET = "secretkeysecretkeysecretkeysecretkeysecretkeysecretkey";
    private const string MERCHANT_ID = "THXXXXXXXX";
    private const string TOKEN = "tokentokentokentokentoken...";

    public static async Task Main(string[] args)
    {
        var req = new {
            merchant_id = MERCHANT_ID,
            token = TOKEN,
            time = DateTimeOffset.UtcNow.ToUnixTimeSeconds()
        };

        var postData = JsonConvert.SerializeObject(req);
        var signature = GenerateHmacSha256(postData, SECRET);

        using (var client = new HttpClient())
        {
            var request = new HttpRequestMessage(HttpMethod.Post, API_URL);
            request.Content = new StringContent(postData, Encoding.UTF8, "application/json");
            request.Headers.Add("X-Signature", signature);

            var response = await client.SendAsync(request);
            var result = await response.Content.ReadAsStringAsync();
            Console.WriteLine(result);
        }
    }

    public static string GenerateHmacSha256(string message, string secret)
    {
        byte[] keyBytes = Encoding.UTF8.GetBytes(secret);
        byte[] dataBytes = Encoding.UTF8.GetBytes(message);

        using (var hmac = new HMACSHA256(keyBytes))
        {
            byte[] hashBytes = hmac.ComputeHash(dataBytes);
            return BitConverter.ToString(hashBytes).Replace("-", "").ToLower();
        }
    }
}