Invoice and Daily Sales Report System

Overview

The Invoice and Daily Sales Report System is a microservice-based application that allows users to create invoices for sales transactions and automatically generates a daily sales summary report. The report is sent via email at 12:00 PM each day. The system utilizes NestJS, MongoDB, RabbitMQ, and Docker to provide a scalable and reliable solution.

Key Features

• Invoice Creation: Create invoices with customer details, items, and amounts.
• Daily Sales Report: Automatically generates a daily sales summary report at noon every day.
• Email Notification: The report is sent via a RabbitMQ queue, where a consumer service processes and sends the report via email.
• Microservice Architecture: Separates responsibilities into two services (invoice-service and email-sender), ensuring better maintainability and scalability.

Prerequisites

• Node.js (version 14.x or later)
• npm (comes with Node.js)
• Docker and Docker Compose
• Nest CLI: Install globally with npm install -g @nestjs/cli

Running the Application

To run the entire application, including installing dependencies and building the services, use Docker Compose with the following command:

docker-compose up --build

This command will:

• Build the Docker images for both invoice-service and email-sender, installing necessary dependencies.
• Start MongoDB and RabbitMQ.
• Launch both services (invoice-service and email-sender).

Services Started:

• MongoDB: Accessible at port 27017 (default).
• RabbitMQ: Management interface accessible at http://localhost:15672 (default user: guest, password: guest).
• Invoice Service: Accessible at http://localhost:3000.
• Email Sender Service: Runs in the background, processing messages from RabbitMQ.

API Endpoints

Invoice Service

• POST /invoices: Create a new invoice

{
  "customer": "John Doe",
  "amount": 150,
  "reference": "INV12345",
  "items": [
    { "sku": "ITEM001", "qt": 2 },
    { "sku": "ITEM002", "qt": 1 }
  ]
}

• GET /invoices/

Retrieve a specific invoice by ID

• GET /invoices: Retrieve a list of all invoices

Testing

Both services include unit and integration tests. To run the tests, navigate to each service directory and run:

# For invoice-service
cd invoice-service
npm run test

# For email-sender
cd email-sender
npm run test