YouTube Downloader

A modern, feature-rich web application for downloading YouTube videos as MP3 files. Built with a robust Go backend and a dynamic, responsive frontend.

Initial Page	Download Options

Key Features

• Asynchronous Downloads: Utilizes Go's concurrency with goroutines to process downloads in the background, allowing the server to handle multiple users simultaneously without blocking.
• Live Status Updates: Employs Server-Sent Events (SSE) to push real-time progress updates (e.g., "Processing", "Complete", "Failed") to the user's browser.
• Dynamic Frontend: The UI is built with vanilla JavaScript, using AJAX for form submissions and dynamically updating the page content without requiring a full reload.
• Internationalization (i18n): Fully localized interface supporting both English and Serbian, with language detection and a manual switcher.
• Modern UI/UX: Features a clean, responsive design with light/dark themes, video thumbnail previews, file size display, and state persistence across page reloads using sessionStorage.
• Audio Quality Control: Allows users to select from multiple quality presets (Low, Medium, High) to balance file size and audio quality.
• Custom Filenames: Lets users easily edit the MP3 filename in the UI before downloading for better file organization.
• Audio Normalization: Provides an option to normalize audio to a standard volume level, ensuring a consistent listening experience across different tracks.
• Playlist Safe: Intelligently handles URLs that are part of a playlist, downloading only the single video specified by the user.
• No Ads, No Fees: A clean, user-focused experience with no advertisements or hidden costs.

Built With

This project was brought to life with these modern technologies:

Technology	Description
Go (Golang)	The core language for the backend server, chosen for its performance and concurrency features.
Vanilla JavaScript (ES6+)	Used for all client-side logic, including AJAX, DOM manipulation, and handling Server-Sent Events.
yt-dlp	A powerful command-line tool used by the backend to handle the downloading from YouTube.
ffmpeg	An essential external program used by yt-dlp to perform the audio conversion to MP3.
go-i18n/v2	The Go library used to manage the application's internationalization and translations.

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Prerequisites

To run this project locally, you must have the following installed and available in your system's PATH.

• Go (version 1.22 or later)

• yt-dlp & ffmpeg:

  macOS

  brew install yt-dlp/taps/yt-dlp ffmpeg

  Linux

  sudo apt update && sudo apt install yt-dlp ffmpeg

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Getting Started

Docker (Recommended)

The easiest way to run this application is using Docker. No need to install Go, yt-dlp, or ffmpeg.

  git clone https://github.com/vukan322/yt-mp3-go.git
  cd yt-mp3-go
  docker-compose up --build

Or manually with Docker:

  docker build -t yt-mp3-downloader .
  docker run -p 8080:8080 -v ./downloads:/app/downloads -v ./cookies.txt:/app/cookies.txt:ro yt-mp3-downloader

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Local Development

1. Clone the repository:

   git clone https://github.com/vukan322/yt-mp3-go.git
   cd yt-mp3-go

2. Set up your environment: Copy the example environment file and edit it if needed.

   cp .env.example .env

3. Tidy dependencies: This will download the required Go modules.

   go mod tidy

4. Make build script executable: You only need to do this once.

   chmod +x build-assets.sh

5. Run the application:

   make run

   OR

   ./build-assets.sh && go run cmd/server/main.go

Access the Application

Open your browser and navigate to http://localhost:8080/yt-downloader.

Configuration

The application is configured using environment variables, which are loaded from an .env file during local development.

Variable	Description	Default
APP_ENV	The application environment (development or production).	development
DOMAIN	The domain the application is running on.	localhost
PORT	The port the application will listen on.	8080
BASE_PATH	The URL path prefix for the application.	/yt-downloader

Deployment

This project is configured for continuous deployment using GitHub Actions.

• Trigger: A push to the main branch automatically triggers the build and deployment workflow.
• Strategy: The deployment is atomic, meaning it uses a timestamped release directory and a current symlink to ensure zero downtime.
• Versioning: The application version is automatically injected at build time. The format is MAJOR.MINOR.PATCH, where the PATCH number is the GitHub Actions run number.

License

This project is licensed under the MIT License - see the LICENSE file for details.