GitHub Profile Analyzer API

A production-ready Node.js backend service that analyzes GitHub user profiles using the GitHub REST API, generates developer insights, and persists the results in a MySQL database for fast querying and analytics.

Overview

GitHub Profile Analyzer is a RESTful API built with Node.js, Express.js, MySQL, and the GitHub Public API.

The service allows users to:

Synchronize GitHub profiles into a local database
Generate repository-based developer insights
Store profile analytics for future access
Search developers by primary programming language
Retrieve top influencers based on GitHub stars
Generate ecosystem-level analytics
Avoid unnecessary GitHub API calls using change detection

The application follows a layered architecture with clear separation between:

Controllers
Services
Repositories
Middleware
Utilities
Database Layer

Features

Core Features

GitHub Profile Synchronization

Fetches public GitHub profile information and repository metadata.

Example:

POST /api/users/sync/octocat

Collected profile data includes:

GitHub ID
Username
Name
Company
Blog
Location
Public Repository Count
Followers
Following

Insight Generation

The system analyzes repositories and generates:

Insight	Description
Total Stars	Sum of stars across all repositories
Total Forks	Sum of forks across all repositories
Top Language	Most frequently used language
Repository Count	Public repository count
Followers	Social influence metric

Example:

{
  "totalStars": 1540,
  "totalForks": 231,
  "topLanguage": "TypeScript"
}

Smart Sync Optimization

Before processing repositories, the application compares:

stored.updated_at === github.updated_at;

If no changes are detected:

{
  "status": "UNCHANGED",
  "message": "GitHub profile unchanged"
}

This reduces:

GitHub API consumption
Response time
Rate-limit exposure

Local Database Access

Fetch previously synchronized profiles without contacting GitHub.

GET /api/users/local/:username

Analytics Dashboard Endpoint

Provides system-wide analytics.

GET /api/users/analytics

Returns:

Total synced users
Average repositories
Ecosystem impact score
Top influencer

Top Influencers Ranking

GET /api/users/top?limit=10

Ranks users by:

total_stars DESC

Language Based Search

GET /api/users/search?language=TypeScript

Find developers whose primary language matches the requested ecosystem.

Health Monitoring

GET /health

Returns:

Uptime
Memory usage
Node version
Database status
Timestamp

Architecture

Client
  |
  v
Routes
  |
  v
Controllers
  |
  v
Services
  |
  v
Repositories
  |
  v
MySQL Database

Layer Responsibilities

Routes

Responsible for:

URL mapping
Validation middleware
Controller delegation

Files:

src/routes/
├── userRoutes.js
└── healthRoutes.js

Controllers

Handle HTTP requests and responses.

Files:

src/controllers/
├── userController.js
└── healthController.js

Services

Contain business logic.

Files:

src/services/
├── githubService.js
├── insightService.js
├── syncService.js
└── userService.js

Responsibilities:

GitHub communication
Insight generation
Synchronization workflow
Analytics processing

Repository Layer

Handles database operations.

src/repositories/
└── userRepository.js

Middleware

src/middleware/
├── errorMiddleware.js
└── validateRequest.js

Provides:

Global error handling
Request validation

Utilities

src/utils/
├── AppError.js
├── asyncHandler.js
├── githubErrorHandler.js
└── validateUser.js

Project Structure

github-profile-analyzer/
│
├── src/
│   ├── config/
│   │   ├── env.js
│   │   └── githubClient.js
│   │
│   ├── controllers/
│   │   ├── healthController.js
│   │   └── userController.js
│   │
│   ├── db/
│   │   ├── connection.js
│   │   └── connectWithRetry.js
│   │
│   ├── middleware/
│   │   ├── errorMiddleware.js
│   │   └── validateRequest.js
│   │
│   ├── repositories/
│   │   └── userRepository.js
│   │
│   ├── routes/
│   │   ├── healthRoutes.js
│   │   └── userRoutes.js
│   │
│   ├── services/
│   │   ├── githubService.js
│   │   ├── insightService.js
│   │   ├── syncService.js
│   │   └── userService.js
│   │
│   ├── tests/
│   │   └── user.test.js
│   │
│   ├── utils/
│   │   ├── AppError.js
│   │   ├── asyncHandler.js
│   │   ├── githubErrorHandler.js
│   │   └── validateUser.js
│   │
│   └── app.js
│
├── docker-compose.yml
├── dockerfile
├── init.sql
├── package.json
└── README.md

Technology Stack

Backend

Node.js
Express.js

Database

MySQL 8

Validation

Zod

HTTP Client

Axios
Axios Retry

Security

Helmet
Express Rate Limit

Logging

Morgan

Testing

Jest
Supertest

Containerization

Docker
Docker Compose

Security Features

Helmet

Adds security headers:

app.use(helmet());

Rate Limiting

max: 100 requests
window: 15 minutes

Protects API from abuse.

Input Validation

Implemented using Zod.

Example:

usernameSchema;

Validates:

Length
Format
Consecutive hyphens
Illegal characters

Request Size Limits

10kb

Protection against payload abuse.

Environment Validation

All environment variables are validated at startup.

Application fails fast if required variables are missing.

Database Schema

Table: github_users

CREATE TABLE github_users (
    github_id BIGINT PRIMARY KEY,
    login VARCHAR(255) UNIQUE,
    name VARCHAR(255),
    company VARCHAR(255),
    blog VARCHAR(500),
    location VARCHAR(255),

    public_repos INT,
    followers INT,
    following INT,

    total_stars INT,
    total_forks INT,
    top_language VARCHAR(100),

    created_at DATETIME,
    updated_at DATETIME,
    synced_at TIMESTAMP
);

Indexes

idx_login
idx_language
idx_stars
idx_synced_at

Optimized for:

User lookups
Language search
Rankings
Recent synchronization queries

API Documentation

Postman Collection

The project includes a comprehensive Postman collection covering:

Health checks
Profile synchronization
Validation testing
Analytics endpoints
Search functionality
Error handling scenarios

Import Collection

Open Postman
Click Import
Select:

postman/GitHub-Profile-Analyzer.postman_collection.json

Environment Variables

{
  "base_url": "http://localhost:5000"
}

For deployed environments:

{
    "base_url": "https://github-profile-analyzer-production.up.railway.app"
}

Health Check

Request

GET /health

Response

{
  "success": true,
  "database": "connected"
}

Sync GitHub Profile

Request

POST /api/users/sync/octocat

Response

{
  "success": true,
  "status": "UPDATED"
}

Fetch All Profiles

Request

GET /api/users

Fetch Single Stored Profile

Request

GET /api/users/local/octocat

Analytics Summary

Request

GET /api/users/analytics

Top Influencers

Request

GET /api/users/top?limit=5

Search By Language

Request

GET /api/users/search?language=TypeScript

Environment Variables

Create a .env file:

PORT=5000

DB_HOST=localhost
DB_USER=root
DB_PASSWORD=root
DB_NAME=githubdb

GITHUB_TOKEN=your_github_token

Local Development Setup

Clone Repository

git clone <repository-url>
cd github-profile-analyzer

Install Dependencies

npm install

Configure Environment

cp .env.example .env

Update values.

Start MySQL

mysql -u root -p

Create database:

CREATE DATABASE githubdb;

Run schema:

mysql -u root -p githubdb < init.sql

Start Application

Development:

npm run dev

Production:

npm start

Docker Deployment

Run Entire Stack

docker compose up --build

Services:

Service	Port
API	5000
MySQL	3306

Stop Containers

docker compose down

Testing

Frameworks:

Jest
Supertest

Run:

npm test

Validation Test Coverage

The project has been successfully tested against:

Profile Synchronization

✓ Standard user synchronization

✓ High-volume organization accounts

✓ Enterprise repositories

✓ Repeat sync cache detection

Input Validation

✓ Invalid username

✓ Consecutive hyphens

✓ Length violations

✓ Illegal characters

✓ Empty language query

✓ Invalid limits

Database Access

✓ Fetch all users

✓ Fetch local user

✓ Missing user handling

Analytics

✓ Analytics summary

✓ Top influencers

✓ Custom limit values

✓ Language ecosystem filtering

Health Monitoring

✓ Health endpoint

✓ Database connectivity

✓ Runtime metadata

Error Handling

Centralized error architecture.

Examples:

GitHub User Not Found

{
  "success": false,
  "message": "GitHub user not found"
}

Validation Error

{
  "success": false,
  "message": "Invalid GitHub username format"
}

GitHub Rate Limit

{
  "success": false,
  "message": "GitHub API rate limit exceeded"
}

Performance Optimizations

Database Indexing

Optimized search and ranking queries.

Connection Pooling

connectionLimit: 10;

Retry Strategy

GitHub API requests automatically retry transient failures.

Change Detection

Avoids unnecessary synchronization operations.

Future Improvements

Potential enhancements:

Redis caching layer
GitHub GraphQL API integration
Historical profile tracking
Scheduled background synchronization
Pagination support
OpenAPI / Swagger documentation
Authentication & RBAC
Prometheus metrics
CI/CD pipeline
GitHub Actions deployment

Assignment Requirements Mapping

Requirement	Status
Node.js	Completed
Express.js	Completed
MySQL	Completed
GitHub API Integration	Completed
Store Insights	Completed
Persist Data	Completed
Fetch All Profiles API	Completed
Fetch Single Profile API	Completed
Docker Support	Completed
Validation Layer	Completed
Error Handling	Completed
Automated Testing	Completed
Production Hardening	Completed

Author

Yash Chincholi

Backend Developer

Node.js • Express.js • MySQL • REST APIs

Built as part of the GitHub Profile Analyzer Backend Engineering Assignment.

Name		Name	Last commit message	Last commit date
certs		certs
postman		postman
src		src
.dockerignore		.dockerignore
.gitignore		.gitignore
docker-compose.yml		docker-compose.yml
dockerfile		dockerfile
init.sql		init.sql
package-lock.json		package-lock.json
package.json		package.json
readme.md		readme.md

Latest commit

History

Folders and files

Repository files navigation

GitHub Profile Analyzer API

Overview

Features

Core Features

GitHub Profile Synchronization

Insight Generation

Smart Sync Optimization

Local Database Access

Analytics Dashboard Endpoint

Top Influencers Ranking

Language Based Search

Health Monitoring

Architecture

Layer Responsibilities

Routes

Controllers

Services

Repository Layer

Middleware

Utilities

Project Structure

Technology Stack

Backend

Database

Validation

HTTP Client

Security

Logging

Testing

Containerization

Security Features

Helmet

Rate Limiting

Input Validation

Request Size Limits

Environment Validation

Database Schema

Table: github_users

Indexes

API Documentation

Postman Collection

Import Collection

Environment Variables

Health Check

Request

Response

Sync GitHub Profile

Request

Response

Fetch All Profiles

Request

Fetch Single Stored Profile

Request

Analytics Summary

Request

Top Influencers

Request

Search By Language

Request

Environment Variables

Local Development Setup

Clone Repository

Install Dependencies

Configure Environment

Start MySQL

Start Application

Docker Deployment

Run Entire Stack

Stop Containers

Testing

Validation Test Coverage

Profile Synchronization

Input Validation

Database Access

Analytics

Health Monitoring