eventhub/modules/payment

Payment Module

The Payment module provides reusable APIs and UI integration for creating payment requests and completing PayPal checkout flows. EventHub uses it from the public web application to sell premium organization plans and receive payment completion/failure events.

Module structure

• src/Payment.Domain.Shared: Constants, localization, permissions, and shared contracts.
• src/Payment.Domain: Payment request domain model and domain services.
• src/Payment.Application.Contracts: Application service contracts and DTOs.
• src/Payment.Application: Payment request application services and PayPal integration logic.
• src/Payment.HttpApi: Public HTTP API endpoints.
• src/Payment.Web: MVC/Razor Pages UI integration for checkout pages.
• src/Payment.Admin.*: Admin application services, HTTP APIs, HTTP API clients, and Blazor admin UI.
• src/Payment.EntityFrameworkCore: EF Core mapping for payment entities.

Installation

This module is already included in the EventHub solution and is initialized by the root solution tasks.

When opening the solution in ABP Studio, run or allow the Initialize Solution task from the Default run profile. It starts PostgreSQL/Redis, runs abp install-libs, and executes EventHub.DbMigrator, which applies the EventHub migrations that include this module's tables.

For manual setup from the repository root:

./scripts/initialize-solution.ps1

Or run the individual steps:

./etc/docker/up.ps1
abp install-libs
dotnet run --project src/EventHub.DbMigrator/EventHub.DbMigrator.csproj

The payment module does not have a separate standalone database in this solution; its EF Core mappings are part of the main EventHub database context.

ABP documentation

• Modularity
• Application services
• HTTP APIs
• MVC / Razor Pages UI
• Blazor UI
• Distributed event bus

Usage

1. Create a Payment Request via using IPaymentRequestAppService

2. Build an URL to redirect to checkout page via using IPaymentUrlBuilder

   public class MyPageModel : AbpPageModel
   {
       protected IPaymentRequestAppService PaymentRequestAppService { get; }
       protected IPaymentUrlBuilder PaymentUrlBuilder { get; }
   
       public MyPageModel(
           IPaymentRequestAppService paymentRequestAppService,
           IPaymentUrlBuilder paymentUrlBuilder)
       {
           PaymentRequestAppService = paymentRequestAppService;
           PaymentUrlBuilder = paymentUrlBuilder;
       }
   
       public async Task OnPostAsync()
       {
           var paymentRequest = await PaymentRequestAppService.CreateAsync(new PaymentRequestCreationDto
           {
               Amount = 9.90m,
               CustomerId = CurrentUser.Id.ToString(),
               ProductId = "UniqueProductId",
               ProductName = "Awesome Product"
           });
   
           var checkoutUrl = PaymentUrlBuilder.BuildCheckoutUrl(paymentRequest.Id).AbsoluteUri;
   
           Response.Redirect(checkoutUrl);
       }
   }
   

---

Distributed Events

• Payment.Completed (PaymentRequestCompletedEto): Published when a payment is completed. Completion can be triggered via webhook or callback. Source doesn't affect to the event. Event will be triggered once.
  • PaymentRequestId: Represents PaymentRequest entity Id.
  • ExtraProperties: Represents ExtraProperties of PaymentRequest entity. You can use this properties to find your related objects to that payment.
• Payment.Failed(PaymentRequestFailedEto): Published when a payment is failed.
  • PaymentRequestId: Represents PaymentRequest entity Id.
  • FailReason: Reason of failure from payment provider (PayPal)
  • ExtraProperties: Represents ExtraProperties of PaymentRequest entity.

Webhook Handling

You have to make some configuration for webhooks on PayPal Dashboard.

If you test it locally, you can use ngrok to open your localhost to world

0. Deploy eventhub or open your ip:port to public. Your HttpApi.Host must be accessible from all over the world.

1. Go to Application List. Find your app and go details. (You can use my account below)

PayPal Account Credentials

info@enisnecipoglu.com 1q2w3E**

Use following temp number for two factor authentication verification: https://receive-smss.com/sms/48722717428/

(Yes the star (*) is doubled. min password length requirement was 8)

2. At the bottom of page you'll see the Webhooks section

3. Click to Add Webhook button and use following values:

   • Webhook URL: https://yourhttpapihosturl.com/api/payment/requests/webhook (replace hostname with your API public url)
   • Event types: Checkout order approved, Checkout order completed