Receipt Processor

This project is a receipt processor that includes the endpoints POST /receipts/process and GET /receipt/{id}/points. Additionally, tests have been added to facilitate easier testing of different scenarios.

My inclination was to try and incorporate DDD principles in the code since this was something quite important to several repos I have worked in and I have found it quite helpful.

NOTE: This project builds upon a template I previously developed (see danyeric123/backend-service). While the template provided a foundation, most of the code is newly written specifically for this project.

Features
Project Structure
Getting Started
Background

Features

Dockerized Setup: Easily set up and run the application using Docker and Docker Compose.
PostgreSQL Integration: Pre-configured to connect to a PostgreSQL database.
Structured Logging: Uses logrus for structured logging.
Environment Variables: Uses environment variables for configuration.
Dependency Injection: Makes the code more testable and modular.
GORM Integration: Uses GORM for ORM, making it easier to work with the database.

Project Structure

receipt-processor/
├── cmd/
│   └── main.go
├── db/
│   ├── config.go
│   ├── models.go
│   ├── receipt.go
│   └── receipt_test.go
├── domain/
│   ├── receipt.go
│   └── receipt_test.go
├── handlers/
│   └── receipt.go
├── Dockerfile
├── docker-compose.yaml
├── go.mod
├── go.sum
├── Makefile
└── README.md

Getting Started

To use this template repo, follow these steps:

Clone the Repository: Clone this repository to your local machine.username and REPO_NAME is the new name of the repository.

Set Up Environment Variables: Create a .env file in the root directory with the following variables:

POSTGRES_USER=your_postgres_user
POSTGRES_PASSWORD=your_postgres_password
POSTGRES_DB=your_postgres_db
POSTGRES_HOST=db

Build and Run: Use the provided Makefile commands to build and run the application.

Prerequisites

Docker
Docker Compose

Running the Application

NOTE: You will need to have an .env file for POSTGRES_DB POSTGRES_USER, POSTGRES_PASSWORD, POSTGRES_HOST (see below)

Build the Docker images:
```
make build
```
Run the application:
```
make run
```
Access the application at http://localhost:8080.

Cleaning Up

To stop and remove the Docker containers, run:

make clean

Commands

make help - Show this help message
make check_env - Check if .env file exists
make check_network - Check if Docker network exists and create it if not
make build - Build Docker containers
make run - Run Docker containers, rebuild if needed
make clean - Stop and remove Docker containers
make fmt - Format code
make lint - Lint code
make test - Run tests
make test_package - Run tests in a specific package

Environment Variables

Set the following environment variables in your .env file or in your environment:

POSTGRES_USER: The PostgreSQL user
POSTGRES_PASSWORD: The PostgreSQL password
POSTGRES_DB: The PostgreSQL database name
POSTGRES_HOST: The PostgreSQL host (usually db when using Docker Compose)

Background

Choice of Language

I work with Golang for several projects and given FetchRewards uses it, I saw it as a great opportunity to practice my skills in setting up a repository from scratch.

Explanation of Chosen Packages

logrus: logrus is used for structured logging. It provides log levels, hooks, and formatters, making it a powerful and flexible logging library compared to the standard log package.
mux: mux is a powerful URL router and dispatcher for matching incoming requests to their respective handler. Though the standard library's http package would suffice, mux appears to be the standard.
- As I wrote it, I thought to use fiber or chi but I felt like there was too much custom features that might not be ideal within the Golang world, which values a more Unix philosophy
gorm: gorm is an ORM library for Go. It simplifies database interactions and allows you to think in terms of Domain-Driven Design (DDD).

Specific Choices

Some specific choices have comments on assumptions or how things might be done differently with more time.

# README