PeekPay

About   |    Stack   |    How to run   |    Specifications

About

PeekPay is a server-side application responsible to create orders, append payments to orders and filter them.

This project was built in order to present as a tech test to Peek, for a Software Engineer hole

Stack

• Kotlin
• Spring Boot
• H2
• JUnit
• Mockk

How to Run

• Requirements

  • Make sure you have Java JDK 17 installed and configured into your machine (you can run java -version to check)
  • You
  • You must have connection internet to download all libraries (but I'm sure you have because you are reading this on GitHub)

To run it, just enter the root folder and run a simple command, as below:

  $ cd peekpay
  
  $ make up

If you wish to execute only the test suite, run:

  $ make test-app

Specifications

This application doesn't provide any web layer, so practically speaking you don't need to run it. The project organization (folders and packages) where built in the intention to split each responsibility, and inside each one we can see a domain-separation package:

├── persistence       ->     Storage layer, responsible to communicate to the database and execute all DB transactions
│   ├── customer      ->     Customer domain's persistence logics 
│   ├── order         ->     Order domain's persistence logics
│   └── payment       ->     Payment domain's persistence logics
├── usecase           ->     Business Logic layer, responsible to orchestrate the logic between domain services
│   ├── customer      ->     Customer domain's business rules
│   ├── order         ->     Order domain's business rules
│   └── payment       ->     Payment domain's business rules
├── core              ->     Layer responsible to run the application
│   └── AppBoot       ->     This is where the main() function should be

Inside the usecase layer, we can find our 4 principal methods in two different places:

• OrderService - Here is where we can find the create_order and get_order methods;
• PeekPayService - Here we can find the apply_payment_to_order, create_order_and_pay and get_orders_for_customer

They were built in 2 different places mainly for 2 reasons:

1. As this app doesn't have a web layer and I wasn't familiar with GraphQL, I preferred to not take a risk trying to implement it and delay this feature;
2. The OrderService component grabs those two methods because they don't depend on any other context. In the meanwhile PeekpayService was created to handle more than one context, and orchestrate the responsibilities between them (e.g. create an order and then create a payment for this order.)