Car Lease Application

Prerequisites

• Bash capable shell
• JDK 11 installed and configured in $JAVA_HOME
• Maven
• Docker installed and running
• Docker Compose installed
• Curl command installed

Build

In the root of this project, execute

mvn clean package

Env

Copy ./.env.example into ./.env

You can change the password if you wish, but not necessary.

Run

In the root of this project, execute

sudo docker-compose down && sudo docker-compose up --build

You may not need to use sudo, depending on how your docker / user permissions are configured

Please wait for the docker compose to complete starting, there may be some netflix errors as the services attempt to contact the discovery server, I did not use health checks for this demo

Initialize

In the root of this project, execute the database init scripts:

• ./scripts/init_cars.sh
• ./scripts/init_customers.sh

This will post records to the customer and car databases, through the API Gateway.

If there are errors, once again, it takes some time (not more than a minute or two) for the services to be completely available.

Test

Navigate to any of the Swagger pages

• http://localhost:8080/customer/swagger-ui/
• http://localhost:8080/car/swagger-ui/
• http://localhost:8080/lease/swagger-ui/

You can then execute calls against the APIs from there.

For the Lease Rate Calculation, you can enter the following:

• make = BMW
• model = XM
• body =

    {
      "mileage":45000,
      "duration":60,
      "interestRate": 0.045
    }

You will notice that the netPrice value of 63000 is configured on the vehicle in the database.

Accomplished

• You can maintain (read, add, change, and delete) basic customer attributes (API Only)
• You can maintain basic car attributes (API only)
• Calculation of the Lease Rate
• service-2-service communication happens in the LeaseServiceImpl Bean, where it looks up the car service API and fetches the value from there.

Missing

I did not manage to get the OAuth working. I'm sure if I had another few hours I would have got it!

I would have used a keycloak server, and the spring boot security mechanisms, with the authentication happening on the edge of the API Gateway.

I also did not create a UI.

I did not unit test every single piece of code, I focused on the calculation itself and testing some of the API endpoints

Hardly any javadocs, sorry!

Bonus Objectives

• It is containerized
• There is a swagger (I could have made this better with time)
• The data is persistent in a MySQL database (also, I chose MySQL, but in retrospect I should have used Mongo)

How I do this in real life?

Currently, I do this on AWS, using the Cloud Development Kit on Cloud Formation. I avoid using long running wherever possible, preferring serverless solutions.

I would have liked to demo that, but one of the requirements was Spring Boot, and I have zero experience using it with AWS, but I'd love to learn!