steve-noel/USMobileTH

The usmobile take home assignment

USMobile Take Home

This is a Spring Boot microservice that provides RESTful APIs to manage billing cycles, user profiles, and daily usage data.

Table of Contents

• Thought Process
• Technologies
• Setup Instructions
• Running With Docker
• Testing
• Documentation
• Improvements

Thought Process

I will use Spring Boot 3.x and Java 22 to create a Restful microservice. I will use a free MongoDb Atlas database (the database credentials are inside the application.yaml file) to store the data. To insert initial data in the database I will use the Mongock database migration library. This allows me to write database migrations inside the codebase. For simplicity, I will use the Lombok library to make working with the java objects easier. Lombok also makes logging easier as well. I will use the testContainer library to add an embedded Mongo database to the integration tests.

Two of the required endpoints(create/update) deal with the user collection, I will create a user controller that contains both of these endpoints. The create endpoint should be a POST since it is creating a new user and the update endpoints should be a PUT since it is updating an existing user.

One of the endpoints fetches a users cycle history, I will create a cycle controller that defines this endpoint. This endpoint should be a GET request as it is fetching data from the service.

One of the endpoints fetches a users daily usage for the current cycle, I will create a dailyUsage controller that defines this endpoint. This endpoint should be a GET request as it is fetching data from the service.

Technologies

• Java 22
• Spring Boot 3.x
• MongoDB
• Maven
• JUnit 5
• Lombok
• Mongock
• TestContainers

Setup Instructions

Prerequisites

• Java 22
• Maven 3.6 or higher

Installation

1. Clone the repository:

   git clone https://github.com/steve-noel/USMobileTH.git
   cd USMobileTH

2. Build the project:

   mvn clean install

3. Run the Spring Boot Application

   mvn spring-boot:run

Running With Docker

Make sure you have docker installed your computer.

1. To build the Docker image, navigate to the root directory containing the Dockerfile and run:

   docker build -t us-mobile-th  .

2. To run the Docker container, use the following command:

   docker run -p 8080:8080 us-mobile-th

Testing

Running the tests require you to have docker installed.

To run the unit & integration tests run

mvn test

Documentation

API documentation is available through Swagger. Once the application is running, navigate to http://localhost:8080/api/v1/swagger-ui/index.html to view the API documentation and test endpoints interactively.

Improvements

• Create a unique constraint in the user collection on email so two users cant have the same email.
• Add more validation to the API endpoints(ex. usedInMb should be a positive integer).
• Add pagination to endpoints that return a list of results.
• Add indexes to the daily_usage/cycle collections on (userId and mdn) to speed up queries.
• Add createDate & updatedDate to all collections for auditing purposes.
• Add JWT authentication to each endpoint in the API.
• Return better error messages from the API.