OPay Refund Payment API

                        
                            import com.google.gson.Gson;
                            import org.apache.commons.codec.binary.Hex;
                            import javax.crypto.Mac;
                            import javax.crypto.spec.SecretKeySpec;
                            import java.io.BufferedReader;
                            import java.io.InputStreamReader;
                            import java.io.OutputStream;
                            import java.net.HttpURLConnection;
                            import java.net.URL;
                            import java.nio.charset.StandardCharsets;
                            import java.util.TreeMap;
                            import java.util.UUID;

                            public class PaymentRefund {

                                private static final String privateKey = "OPAYPRV*******0187828";

                                private static final String endpoint = "https://sandboxapi.opaycheckout.com";

                                private static final String merchantId = "256621051120756";

                                public static void main(String[] args) throws Exception {
                                    String addr = endpoint + "/api/v1/international/payment/refund/create";
                                    Gson gson = new Gson();
                                    TreeMap order = new TreeMap<>();
                                    TreeMap amount = new TreeMap<>();
                                    amount.put("currency","EGP");
                                    amount.put("total",new Integer(200));
                                    order.put("amount",amount);
                                    order.put("callbackUrl","https://your-call-back-url.com");
                                    order.put("country","EG");
                                    order.put("originalReference", "fb5ed330-edc1-4c2b-99e2-6b865cdf88f2");
                                    order.put("reference", UUID.randomUUID().toString());

                                    String requestBody = gson.toJson(order);
                                    System.out.println("--request:");
                                    System.out.println(requestBody);
                                    String oPaySignature = hmacSHA512(requestBody, privateKey);
                                    System.out.println("--signature:");
                                    System.out.println(oPaySignature);

                                    URL url = new URL(addr);
                                    HttpURLConnection con = (HttpURLConnection)url.openConnection();
                                    con.setRequestMethod("POST");
                                    con.setRequestProperty("Content-Type", "application/json; utf-8");
                                    con.setRequestProperty("Authorization", "Bearer "+oPaySignature);
                                    con.setRequestProperty("MerchantId", merchantId);
                                    con.setDoOutput(true);
                                    OutputStream os = con.getOutputStream();
                                    byte[] input = requestBody.getBytes(StandardCharsets.UTF_8);
                                    os.write(input, 0, input.length);
                                    BufferedReader br = new BufferedReader(new InputStreamReader(con.getInputStream(), StandardCharsets.UTF_8));
                                    StringBuilder response = new StringBuilder();
                                    String responseLine = null;
                                    while ((responseLine = br.readLine()) != null) {
                                        response.append(responseLine.trim());
                                    }

                                    System.out.println("--response:");
                                    System.out.println(response.toString());
                                    //close your stream and connection
                                }

                                public static String hmacSHA512(final String data, final String secureKey) throws Exception{
                                    byte[] bytesKey = secureKey.getBytes();
                                    final SecretKeySpec secretKey = new SecretKeySpec(bytesKey, "HmacSHA512");
                                    Mac mac = Mac.getInstance("HmacSHA512");
                                    mac.init(secretKey);
                                    final byte[] macData = mac.doFinal(data.getBytes());
                                    byte[] hex = new Hex().encode(macData);
                                    return new String(hex, StandardCharsets.UTF_8);
                                }
                            }

                        
                    

                        
                            using System;
                            using System.IO;
                            using System.Linq;
                            using System.Net;
                            using System.Text;
                            using Newtonsoft.Json;
                            namespace OPayRequest
                            {
                                public class Program
                                {
                                    static void Main(string[] args)
                                    {
                                        PostJson("https://sandboxapi.opaycheckout.com/api/v1/international/transaction/refund  ", new opay_request
                                        {
                                            reference    = '12312321324',
                                            originalReference    = '1001000',
                                            orderNo  = '10343543543532432',
                                        });
                                    }

                                    private static void PostJson(string uri, opay_request postParameters)
                                    {
                                        string postData = JsonConvert.SerializeObject(postParameters);
                                        byte[] bytes = Encoding.UTF8.GetBytes(postData);
                                        var httpWebRequest = (HttpWebRequest) WebRequest.Create(uri);
                                        httpWebRequest.Method = "POST";
                                        httpWebRequest.ContentLength = bytes.Length;
                                        httpWebRequest.ContentType = "text/json";
                                        using (Stream requestStream = httpWebRequest.GetRequestStream())
                                        {
                                            requestStream.Write(bytes, 0, bytes.Count());
                                        }
                                        var httpWebResponse = (HttpWebResponse) httpWebRequest.GetResponse();
                                        if (httpWebResponse.StatusCode != HttpStatusCode.OK)
                                        {
                                            string message = String.Format("GET failed. Received HTTP {0}", httpWebResponse.StatusCode);
                                            throw new ApplicationException(message);
                                        }
                                    }
                                }

                                public class opay_request
                                {
                                    public string reference { get; set; }
                                    public string orderNo { get; set; }
                                }
                            }