Billing Management System

A comprehensive solution for managing customer billing, usage tracking, and stakeholder approvals.

Tech Stack

• Backend: Ruby on Rails
• Database: PostgreSQL
• Frontend: React with Redux

Features

• User Authentication: Secure login using BCrypt
• Role-based Access Control:
  • Finance: Generate and send bills
  • Customer Success & Sales: Approve or reject bills
• Bill Tracking: Comprehensive action history with documentation and reversibility
• Customer Management: Track details, preferences, and API usage
• Usage Monitoring: Record and analyze customer API consumption
• Flexible Billing: Generate bills based on usage and custom limits

Database Schema

Users

Column Name	Data Type	Details
id	integer	primary key, not null
name	string	not null, indexed, unique
email	string
role	string	not null
password_digest	string	not null
session_token	string	not null, indexed, unique

Roles: "Finance", "Customer Success", "Sales"

Customers

Column Name	Data Type	Details
id	integer	primary key, not null
csm_id	integer	foreign key (users), indexed
name	string
billing_address	string
billing_email	string
monthly_api_limit	integer
overage_unit_cost	float
start_date	date
end_date	date
require_csm_approval	boolean

Usage

Column Name	Data Type	Details
id	integer	primary key, not null
customer_id	integer	foreign key (customers), not null
month	integer
year	integer
api_usage	integer

Bills

Column Name	Data Type	Details
id	integer	primary key, not null
customer_id	integer	foreign key (customers), not null
month	integer
year	integer
overage_units	integer
overage_unit_cost	float
overage_amount	float
status	string
created_at	datetime
updated_at	datetime

Bill Actions

Column Name	Data Type	Details
id	integer	primary key, not null
bill_id	integer	foreign key (bills), not null
stakeholder_id	integer	foreign key (users), not null
action	string
comment	string
created_at	datetime	not null
updated_at	datetime	not null

API Endpoints

HTML API

• GET / - Load React web app

JSON API

Users

• GET /api/users/:userId
• POST /api/users

Sessions

• POST /api/session
• DELETE /api/session

Customers

• GET /api/customers
• GET /api/customers/:customerId

Usage

• GET /api/usage (with query parameters)

Bills

• GET /api/bills
• GET /api/bills/:billId
• POST /api/bills
• PATCH /api/bills/:id/approve
• PATCH /api/bills/:id/reject

Frontend Routes

• /welcome - Login and Signup
• /dashboard - Main Dashboard with Overage Bill Index
• /bills/:id - Bill Details
• /customers - Customer List
• /customers/:id - Customer Details with Usage

Additional Notes

• Bill creation or updates automatically generate BillActions for activity logging.
• The overage_unit_cost is stored in both Customer and Bill models for flexibility.
• The system supports custom approval workflows based on customer preferences.

Getting Started

1. Clone the repository
2. Install dependencies:

   bundle install
   npm install
   

3. Set up the database:

   rails db:create
   rails db:migrate
   

4. Start the server:

   rails s
   

5. In a new terminal, start the frontend:

   npm start