🚀 AI Code Reviewer SaaS Platform

An AI-powered SaaS platform that automates Pull Request (PR) reviews using static code analysis + LLM-based insights, built with a production-grade architecture.

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💡 Features

• ✅ Static Code Analysis (AST + Complexity)
• 🤖 AI Code Review (LLM suggestions)
• 🔄 GitHub PR Integration (auto comments)
• 📊 Dashboard for PR analytics
• 🔐 JWT Authentication & API Keys
• 📈 Usage Limits (Free / Pro tiers)
• ⚡ Async Processing with Celery

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🧱 Tech Stack

Backend

• FastAPI
• Celery + Redis
• MongoDB

Frontend

• Next.js
• Tailwind CSS

AI & Analysis

• OpenAI API
• Radon (Cyclomatic Complexity)
• Python AST

DevOps

• Docker & Docker Compose
• Ngrok (Webhook testing)

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📁 Project Structure

backend/
├── analysis_engine/
├── auth/
├── celery_apps/
├── config/
├── db_services/
├── github_service/
├── schemas/
└── main.py

frontend/
docker-compose.yml

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⚙️ Setup Instructions

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🔹 1. Clone Repository

git clone https://github.com/YOUR_USERNAME/ai-code-reviewer.git
cd ai-code-reviewer

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🔹 2. Backend Setup

Create Virtual Environment

cd backend
python -m venv .venv
source .venv/bin/activate   # Linux/Mac
.venv\Scripts\activate      # Windows

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Install Dependencies

pip install -r requirements.txt

If no requirements file:

pip install fastapi uvicorn pymongo python-dotenv celery redis passlib[bcrypt] python-jose requests PyGithub radon openai

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🔹 3. Environment Variables

Create .env inside backend/:

OPENAI_API_KEY=your_openai_key
GITHUB_TOKEN=your_github_token
SECRET_KEY=your_secret_key

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🔹 4. Run Services (Docker)

From project root:

docker compose up -d

This starts:

• MongoDB
• Redis

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🔹 5. Run Backend

cd backend
uvicorn main:app --reload

Access API:

http://127.0.0.1:8000/docs

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🔹 6. Run Celery Worker

Open new terminal:

cd backend
celery -A celery_apps.celery_app worker --loglevel=info

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🔹 7. Frontend Setup

cd frontend
npm install
npm run dev

Access frontend:

http://localhost:3000

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🌐 GitHub Webhook Setup (Ngrok)

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🔹 1. Start Ngrok

ngrok http 8000

Copy URL like:

https://abcd1234.ngrok-free.app

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🔹 2. Add Webhook in GitHub

Go to:

Repo → Settings → Webhooks → Add Webhook

Set:

Payload URL:
https://YOUR_NGROK_URL/webhook/github

Content type:
application/json

Events:
Pull Request (opened)

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🔹 3. Secret (Optional)

Match this in backend:

GITHUB_SECRET = "webhook_secret"

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🔄 System Flow

GitHub PR Created
        ↓
Webhook Triggered
        ↓
FastAPI Receives Event
        ↓
Celery Task Queued (Redis)
        ↓
Fetch PR Files
        ↓
Static Analysis (AST + Radon)
        ↓
AI Review (LLM)
        ↓
Store Results (MongoDB)
        ↓
Post Comment to GitHub PR
        ↓
Display in Dashboard

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🧠 Flow Diagram (Architecture)

          ┌───────────────┐
          │   GitHub PR   │
          └──────┬────────┘
                 │ Webhook
                 ▼
        ┌──────────────────┐
        │   FastAPI API    │
        └──────┬───────────┘
               │
               ▼
        ┌───────────────┐
        │   Celery      │
        │   Worker      │
        └──────┬────────┘
               │
   ┌───────────┼────────────┐
   ▼           ▼            ▼
Static     AI Review     GitHub API
Analysis   (LLM)         (Comments)
   │           │            │
   └──────┬────┴────────────┘
          ▼
     MongoDB
          ▼
     Dashboard (Next.js)

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🧪 Testing

API Testing

• Swagger UI → /docs

Auth Testing

• Signup → Login → Use JWT

Webhook Testing

• Use Ngrok
• Create PR → see logs + comments

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🧩 Key Endpoints

Endpoint	Description
POST /auth/signup	Register user
POST /auth/login	Login
POST /auth/register-repo	Add repo
GET /dashboard/my-prs	User PRs
GET /dashboard/analytics	Usage stats
POST /webhook/github	GitHub webhook

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🚀 Future Improvements

• Multi-tenant support
• CI/CD pipeline
• Kubernetes deployment
• Advanced ML risk scoring
• Team collaboration features

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👨‍💻 Author

Bishal Bhandari

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⭐ If you like this project

Give it a star ⭐ and share feedback!