Paystack In Asp.Net MVC

Introduction

Happy new year folks. I hope you all enjoyed your holidays.  Let me enlighten you with some new year codes 😊.

Remember my post on how to implement a payment gateway on Paystack with Node js? today, you would see it in action in Asp.Net.

I am not going to build a customer subscription app like I did in the previous one, rather I would provide explicit codes that can be used to implement payment on any mobile apps, web apps, and any platform indeed. It is a simple code and can be easily integrated into your projects.

To know more about Paystack infrastructure, visit the developer's section on their website. They have already written some libraries on vast programming languages like Python, Java, Node js and so on...

If you have problems working with the code or implementing it on your project, drop your comments and you might receive an email from me or if your company is looking forward to incorporating a payment solution, you can contact me.

Diving to the code

Step 1: Building the payment class and model classes 

using System;

using System.Collections.Generic;

using System.Net;

using System.Net.Http;

using System.Net.Http.Headers;

using System.Threading.Tasks;

using Newtonsoft.Json;

namespace MyApp.Classes

{

    //Note: Don't change the property names to avoid errors 

    public class TransactionResult

    {

        public bool status { get; set; }

        public string message { get; set; }

        public Data data { get; set; }

    }

    //Note: Don't change the property names to avoid errors 

    public class Data

    {

        [JsonProperty("authorization_url")]

        public string authorization_url { get; set; }

        [JsonProperty("access_code")]

        public string access_code { get; set; }

        [JsonProperty("reference")]

        public string reference { get; set; }

    }

    public class Payment

    {

        private readonly string _payStackSecretKey;

        /// <summary>

        /// The secret key is needed for authentication and verification purposes. 

        /// Note: It is best to store the secret key in the web.config file.

        /// </summary>

        /// <param name="secretKey"></param>

        public Payment(string secretKey)

        {

            _payStackSecretKey= secretKey;

            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12; //Don't for get to add this. 

        }

        /// <summary>

        /// Initialize a transaction. Check out documentation on https://developers.paystack.co/docs/initialize-a-transaction

        /// </summary>

        /// <param name="amountInKobo">For eg, 5000000 is 5000 that is "5000*100"</param>

        /// <param name="email">The customer email</param>

        /// <param name="metadata">Additional data can be included. </param>

        /// <param name="resource">The optional api endpoint which is already specified</param>

        /// <returns></returns>

        public async Task<TransactionResult> InitializeTransaction(int amountInKobo, string email, string metadata = "",

            string resource = "https://api.paystack.co/transaction/initialize")

        {

            var client = new HttpClient {BaseAddress = new Uri(resource)};

            client.DefaultRequestHeaders.Add("Authorization", _payStackSecretKey);

            // Add an Accept header for JSON format.

            client.DefaultRequestHeaders.Accept.Add(

               new MediaTypeWithQualityHeaderValue("application/json"));

            var body = new Dictionary<string, string>

            {

                {"amount", amountInKobo.ToString()},

                {"email", email},

                {"metadata", metadata}

            };

            var content = new FormUrlEncodedContent(body);

            var response = await client.PostAsync(resource, content);

            if (response.IsSuccessStatusCode)

            {

                TransactionResult responseData = await response.Content.ReadAsAsync<TransactionResult>();

                return responseData;

            }

            return null;

        }

        /// <summary>

        /// Verify a transaction

        /// </summary>

        /// <param name="reference">The reference code returned from the transaction initialization result </param>

        /// <param name="resource">The optional api endpoint which is already specified</param>

        /// <returns></returns>

        public async Task<string> VerifyTransaction(string reference,string resource = "https://api.paystack.co/transaction/verify")

        {

            var client = new HttpClient {BaseAddress = new Uri(resource)};

            // Add an Accept header for JSON format.

            client.DefaultRequestHeaders.Accept.Add(

                new MediaTypeWithQualityHeaderValue("application/json"));

            client.DefaultRequestHeaders.Add("Authorization", _payStackSecretKey);

            var response = await client.GetAsync(reference + "/");

            if (response.IsSuccessStatusCode)

            {

                string responseData = await response.Content.ReadAsStringAsync();

                return responseData;

            }

            return null;

        }

    }

}

Step 2: Using the class in Asp.net MVC

        //[Authorize]
        public async Task<ActionResult> Pay()
        {
     
            var payment = new PaystackPayment("Bearer secret key goes here");
            var transaction = await payment.InitializeTransaction(500000, "johndoe@gmail.com");
            if (transaction.status)
            {
                //redirect to authorization url
                return RedirectPermanent(transaction.data.authorization_url);
               //return Json(transaction, JsonRequestBehavior.AllowGet);
            }
            return Content("An error occcured");
        }

Conclusion

I hope you have fun coding this. Play with it, tweak it, add it to your project as you like. If you have any issues, let me know right away. Buggy and troublesome codes shouldn't be written in 2017 "I think that should be part of my new year resolution" 😊