Usagey Express Example

This is an example application demonstrating how to integrate Usagey with an Express.js server.

What is Usagey?

Usagey is a complete toolkit for implementing usage-based pricing in your applications. It provides:

• Real-time usage tracking
• Flexible pricing models (per-unit, tiered, hybrid)
• Automated billing
• Analytics and reporting

Features Demonstrated

This example application demonstrates:

1. Server-Side Usage Tracking: How to track usage events from your backend
2. RESTful API Integration: Example API endpoints for tracking and retrieving usage data
3. Pricing Model Implementation: How to calculate costs for different pricing strategies
4. Usage Visualization: Displaying usage data with charts and tables

Getting Started

Prerequisites

• Node.js 14.x or newer
• npm or yarn

Installation

1. Clone this repository

git clone https://github.com/8thwanda/usagey-express-example.git
cd usagey-express-example

2. Install dependencies

npm install
# or
yarn

3. Set up your environment variables

cp .env.example .env

4. Edit .env to add your Usagey API key or set USE_MOCK_DATA=true for demo purposes

5. Start the server

npm start
# or
npm run dev # for development with auto-reload

6. Open http://localhost:3000 in your browser

Project Structure

.
├── lib/                # Library code, including Usagey client setup
│   ├── usagey-client.js # Usagey client wrapper
│   └── pricing-models.js # Pricing model definitions
├── public/             # Static assets
├── routes/             # Express routes
│   ├── api.js          # API routes for usagey operations
│   └── web.js          # Web routes for serving pages
├── views/              # EJS templates
│   ├── partials/       # Reusable template parts
│   ├── index.ejs       # Home page
│   ├── usage-tracking.ejs # Usage tracking demo
│   ├── usage-dashboard.ejs # Dashboard demo
│   └── pricing-demo.ejs # Pricing models demo
├── .env.example        # Example environment variables
├── server.js           # Express server setup
└── README.md           # This file

API Endpoints

Track Usage Event

POST /api/track

Request Body:

{
  "event_type": "api_call",
  "quantity": 1,
  "metadata": {
    "endpoint": "/users",
    "method": "GET"
  }
}

Get Usage Statistics

GET /api/stats

Get Usage Events

GET /api/events?event_type=api_call&limit=10

Parameters:

• event_type: Filter by event type
• start_date: Filter by start date (ISO format)
• end_date: Filter by end date (ISO format)
• limit: Number of events to return (default: 50, max: 1000)

Calculate Cost Based on Pricing Model

POST /api/calculate

Request Body:

{
  "model_id": "tiered",
  "usage": 5000
}

Code Examples

Initialize the Usagey Client

// lib/usagey-client.js
const { UsageyClient } = require('usagey');

function getUsageyClient() {
  const apiKey = process.env.USAGEY_API_KEY;
  
  return new UsageyClient(apiKey, {
    baseUrl: process.env.USAGEY_API_URL || 'https://api.usagey.com',
  });
}

Track a Usage Event

// Example route handler
const { trackEvent } = require('../lib/usagey-client');

router.post('/track', async (req, res) => {
  try {
    const { event_type, quantity = 1, metadata = {} } = req.body;
    
    const result = await trackEvent(event_type, quantity, metadata);
    
    res.status(200).json(result);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

Get Usage Statistics

// Example route handler
const { getUsageStats } = require('../lib/usagey-client');

router.get('/stats', async (req, res) => {
  try {
    const stats = await getUsageStats();
    res.status(200).json(stats);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

Resources

• Usagey NPM Package
• Usagey Documentation
• Express.js Documentation

License

MIT