Bootiful Audio: Speech-to-Text Demo

A demonstration application showcasing Spring AI integration with OpenAI's Whisper model for speech-to-text transcription, built as a native GraalVM application with Vaadin frontend.

Educational Purpose

This repository serves as an educational resource for developers looking to understand:

1. Spring AI Integration - How to leverage Spring AI to connect with OpenAI services
2. GraalVM Native Images - Building efficient, fast-starting native applications
3. Vaadin Web Applications - Creating interactive web UIs with Java
4. Browser Audio APIs - Capturing and processing audio in a browser environment
5. Spring Security - Implementing authentication in web applications
6. DevOps Automation - GitHub Actions and Fly.io deployment integration

Features

• Speech recording directly in the browser
• Real-time audio transcription using OpenAI's Whisper model
• Secure authentication flow
• Responsive UI built with Vaadin
• Optimized for performance with GraalVM native compilation

Technology Stack

• Spring Boot 3 - Application framework
• Spring AI - AI service integration
• GraalVM - Native image compilation
• Vaadin - Web UI framework
• OpenAI Whisper - Audio transcription model
• GitHub Actions - CI/CD pipeline
• Fly.io - Cloud deployment

Getting Started

Prerequisites

• Java 24
• Maven
• OpenAI API key

Environment Variables

The application requires the following environment variables:

SPRING_AI_OPENAI_API_KEY=your_openai_api_key
APP_USER=your_username
APP_PASSWORD=your_password

Running Locally

1. Clone the repository
2. Set up environment variables
3. Run the application:

./mvnw spring-boot:run

For native image compilation:

./mvnw -Pnative,production -B spring-boot:build-image

Architecture

The application follows a simple architecture:

1. Frontend: Vaadin-based UI that captures audio using browser APIs
2. Controller/Service Layer: Processes captured audio and communicates with OpenAI
3. Integration Layer: Spring AI integration with OpenAI Whisper API

Deployment

The application is configured for deployment to Fly.io using GitHub Actions. The workflow is defined in .github/workflows/build-deploy.yml.

Contributing

This project is for educational purposes. Feel free to fork and experiment with the codebase to learn more about the technologies involved.