Subscription Tracker

⚠️ Disclaimer: This is my first module, built for a school assignment and clean code practice. It may not be fully polished.

A JavaScript module for managing and analyzing personal subscriptions. Convert between billing frequencies, identify unused services, analyze cost efficiency and make calculated decisions about which subscriptions to keep or cancel.

Core Features

• ✅ Manage subscription data with validation
• ✅ Convert costs between weekly/monthly/yearly frequencies
• ✅ Track active/inactive status and usage hours
• ✅ Calculate individual and total costs by category
• ✅ Analyze usage efficiency (cost per hour)
• ✅ Identify completely unused subscriptions
• ✅ Identify underutilized subscriptions

Purpose

Subscription Tracker helps individuals take control of their subscription expenses by providing clear insights into spending patterns. This module is designed for both end-users managing personal subscriptions and developers who need subscription management functionality in their applications. The module addresses common problems:

• Converting between different billing frequencies for fair cost comparison
• Identifying unused subscriptions costing you money
• Finding overpriced services relative to your usage
• Calculating total spending across categories
• Making calculated analysis of which subscriptions to keep or cancel

Table of Contents

• Core Features
• Purpose
• Quick Start
• Installation
• Essential API
  • Subscription
  • SubscriptionCollection
  • CostCalculator
  • UsageAnalyzer
• Complete Example
• Requirements
• License
• Versioning
• Author

Quick Start

import { Subscription, SubscriptionCollection, CostCalculator, UsageAnalyzer } from 'subscription-tracker'

// Create and manage subscriptions
const netflix = new Subscription("Netflix", 139, "monthly", "streaming")
const collection = new SubscriptionCollection()
collection.addSubscription(netflix)

// Calculate costs
const calculator = new CostCalculator()
const yearlyCost = calculator.calculateYearlyCost(netflix)
console.log(`Netflix yearly cost: ${yearlyCost} kr`)

// Track and analyze usage
netflix.addUsageHours(25)
const analyzer = new UsageAnalyzer()
const costPerHour = analyzer.analyzeCostPerHour(netflix, calculator)
console.log(`Cost per hour: ${costPerHour.toFixed(2)} kr`)

Installation

# Clone from GitHub
git clone https://github.com/HannaRV/subscription-tracker

Essential API

⚠️ Note: Each class has important usage considerations. See complete API documentation for detailed behavior notes and limitations.

Subscription → Complete Subscription API

const subscription = new Subscription(name, price, frequency, category)
subscription.activate()
subscription.deactivate()
subscription.addUsageHours(hours)

SubscriptionCollection → Complete SubscriptionCollection API

const collection = new SubscriptionCollection()
collection.addSubscription(subscription)
collection.getActiveSubscriptions()
collection.searchSubscriptionsByName(name)

CostCalculator → Complete CostCalculator API

const calculator = new CostCalculator()
calculator.calculateMonthlyCost(subscription)
calculator.calculateTotalMonthlyCost(subscriptions)
calculator.calculateCostByCategory(subscriptions)

UsageAnalyzer → Complete UsageAnalyzer API

const analyzer = new UsageAnalyzer()
analyzer.analyzeCostPerHour(subscription, calculator)
analyzer.findUnderutilizedSubscriptions(subscriptions, calculator, maxCostPerHour)
analyzer.findUnusedSubscriptions(subscriptions)

Complete Example

// Setup subscriptions
const netflix = new Subscription("Netflix", 139, "monthly", "streaming")
const spotify = new Subscription("Spotify", 1200, "yearly", "music")

const collection = new SubscriptionCollection()
collection.addSubscription(netflix)
collection.addSubscription(spotify)

// Add usage data
netflix.addUsageHours(25)
spotify.addUsageHours(50)

// Calculate and analyze
const calculator = new CostCalculator()
const analyzer = new UsageAnalyzer()

const totalMonthlyCost = calculator.calculateTotalMonthlyCost(collection.getAllSubscriptions())
const categoryBreakdown = calculator.calculateCostByCategory(collection.getAllSubscriptions())
const unusedSubs = analyzer.findUnusedSubscriptions(collection.getAllSubscriptions())
console.log(`Completely unused subscriptions: ${unusedSubs.length}`)
const inefficientSubs = analyzer.findUnderutilizedSubscriptions(
    collection.getAllSubscriptions(),
    calculator,
    20 // Max 20 kr/hour
)

console.log(`Total monthly cost: ${totalMonthlyCost} kr`)
console.log('By category:', categoryBreakdown)
console.log(`Inefficient subscriptions: ${inefficientSubs.length}`)

Requirements

• Language: JavaScript (ES2020+)
• Runtime: Node.js >=20.6.0
• Module system: ES6 modules

License

MIT

Versioning

This project uses Semantic Versioning:

• MAJOR version for incompatible API changes
• MINOR version for new functionality
• PATCH version for bug fixes

Current version: 1.0.0

Author

Hanna Rubio Vretby [email protected]