import hmac
import hashlib
import base64
from datetime import datetime

def generate_signature(api_key, device_id, timestamp, api_secret):
    # Create the payload
    payload = f"{api_key}|{device_id}|{timestamp}"

    # Generate HMAC-SHA256
    signature = hmac.new(
        api_secret.encode('utf-8'),
        payload.encode('utf-8'),
        hashlib.sha256
    )

    # Return Base64 encoded signature
    return base64.b64encode(signature.digest()).decode('utf-8')

# Example usage
api_key = 'test_tenant_4Dqms3ygG9FVC'
device_id = 'device-123'
timestamp = datetime.utcnow().strftime('%Y-%m-%dT%H:%M:%SZ')
api_secret = 'your-api-secret'

signature = generate_signature(api_key, device_id, timestamp, api_secret)

using System;
using System.Security.Cryptography;
using System.Text;

public class SignatureGenerator
{
    public static string GenerateSignature(
        string apiKey,
        string deviceId,
        string timestamp,
        string apiSecret)
    {
        // Create the payload
        string payload = $"{apiKey}|{deviceId}|{timestamp}";

        // Generate HMAC-SHA256
        using (var hmac = new HMACSHA256(Encoding.UTF8.GetBytes(apiSecret)))
        {
            byte[] hash = hmac.ComputeHash(Encoding.UTF8.GetBytes(payload));

            // Return Base64 encoded signature
            return Convert.ToBase64String(hash);
        }
    }

    // Example usage
    public static void Main()
    {
        string apiKey = "test_tenant_4Dqms3ygG9FVC";
        string deviceId = "device-123";
        string timestamp = DateTime.UtcNow.ToString("yyyy-MM-dd'T'HH:mm:ss'Z'");
        string apiSecret = "your-api-secret";

        string signature = GenerateSignature(apiKey, deviceId, timestamp, apiSecret);
    }
}