🎮 FastAPI Flutter API Integration

A simple frontend-backend project that exposes a FastAPI REST API back-end and a Flutter frontend to showcase API integration, Pydantic Schemas, Alembic Migrations and SQLAlchemy ORM models.

✳️ Visual Overview

FastAPI-Flutter-Final.mp4

📹 Demo

First, see it in action:

1. Open a terminal and start the backend.

uvicorn app.main:app --reload --host 127.0.0.1 --port 8000

2. In Postman, set the base_url to localhost:8000, the headers to Content-Type:application/json and send a POST /new with the body (below) to create a new fruit.

{
  "name": "Strawberry",
  "seedless": true
}

3. Run the Flutter app on an emulator or device.
4. Switch to the List tab to fetch and view fruits.

🔍 Project Overview

Problem

• Provide a reliable HTTP API for managing fruit records and a simple cross-platform UI for users to view and add fruits.

Key Components

• FastAPI REST endpoints
• SQLAlchemy ORM models
• Alembic migration scripts
• Pydantic schemas for input/output validation
• Flutter UI with bottom navigation
• Dart model mapping TINYINT seedless flag to bool
• HTTP integration tested via Postman

🛠️ Getting Started

1. Clone

git clone https://github.com/ex-rnd/FastAPI-Flutter-API-Integration-Using-Alembic-MySQL.git
cd fastapi-flutter-integration

2. Backend setup

• Create a Python virtual environment.

python3 -m venv venv
source venv/bin/activate   # macOS/Linux
venv\Scripts\activate      # Windows
pip install -r requirements.txt

• Install requirements.

pip install -r requirements.txt

• Create a .env with your MySQL URL.

DATABASE_URL=mysql+pymysql://user:pass@host:3306/dbname

• Run alembic migrations.

alembic upgrade head

3. Frontend setup

• Navigate to the flutter folder.

cd frontend

• Fetch Dart packages.

flutter pub get

• Update lib/config.dart with your API base URL.

▶️ Usage

API Testing with Postman.

• Open Postman.

• Use the Environment to set base_url to http://127.0.0.1:8000.

• Run requests and inspect responses.

• Use GET, POST, PUT.

• Automate tests by creating assertions on status codes and JSON schemas

Flutter Front-End.

• Ensure your emulator or device is connected
• From project root:

cd frontend
flutter run

🚀 API Reference

📐 App Architecture

High level overview

Flutter App  ← HTTP (http package) →  FastAPI  
    ↑                                     │  
    │                                     ↓  
 ListView / Form             SQLAlchemy ORM → MySQL  
                             Alembic Migrations  

Low level overview

[Flutter UI] → http.get/post → [FastAPI App]
  ↓                          ↓
ListView / Form      Pydantic validation
                      ↓
                 SQLAlchemy models
                      ↓
                  MySQL database
               (migrations via Alembic)  

🤝 Contributing

• Fork the repo
• Branch naming: feature/xyz or fix/xyz
• Run linters:

Backend: flake8, black
Frontend: flutter format

• Add tests:

Backend unit tests with: pytest
Frontend widget tests with: flutter test

• Submit PRs with clear descriptions and link related issues

🎮 Thank you for exploring FastAPI-Flutter integration 🎉!