ydl-rs

中文版 | English

A fast, reliable YouTube subtitle downloader library and CLI tool written in Rust. This project provides both a library (ydl) for programmatic access and a command-line interface (ydl-cli) for downloading YouTube subtitles in various formats.

Features

• 🚀 Fast and efficient subtitle downloading
• 📝 Multiple subtitle formats support (SRT, VTT, TXT, JSON, Raw XML)
• 🌐 Language selection for subtitles
• 📊 Video metadata extraction
• 🎯 Automatic subtitle track selection
• 🔄 Retry logic with exponential backoff for reliability
• 📖 Blog post generation from video transcripts (using OpenAI)
• 📄 Automatic plain text extraction when downloading SRT files
• 🛠️ Both library and CLI interfaces

Installation

As a Library

Add ydl to your Cargo.toml:

[dependencies]
ydl = "0.1.0"

As a CLI Tool

Install the CLI tool using cargo:

cargo install ydl-cli

Usage

CLI Usage

Download subtitles

# Download subtitles in SRT format (default)
# Note: When downloading SRT, a plain text file is also automatically saved
ydl https://www.youtube.com/watch?v=VIDEO_ID

# Download subtitles in VTT format
ydl https://www.youtube.com/watch?v=VIDEO_ID --format vtt

# Download subtitles in a specific language
ydl https://www.youtube.com/watch?v=VIDEO_ID --language en

# Save to a specific file
ydl https://www.youtube.com/watch?v=VIDEO_ID --output my_subtitles.srt

# Save to a specific directory
ydl https://www.youtube.com/watch?v=VIDEO_ID --output-dir ./subtitles/

Note: When downloading SRT format subtitles, a plain text file (.txt) containing only the subtitle content (without timestamps) is automatically saved alongside the SRT file. This text file is used for blog generation and can be referenced for other purposes.

Other operations

# List available subtitle tracks
ydl https://www.youtube.com/watch?v=VIDEO_ID --list

# Show video metadata
ydl https://www.youtube.com/watch?v=VIDEO_ID --info

# Generate a blog post from video transcript (requires OpenAI API key)
# This will use the existing .txt file if available, or download fresh subtitles
ydl https://www.youtube.com/watch?v=VIDEO_ID --generate-blog

# Enable verbose logging
ydl https://www.youtube.com/watch?v=VIDEO_ID -v

Library Usage

use ydl::{Ydl, YdlOptions, SubtitleType};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Create options
    let options = YdlOptions::builder()
        .language("en")
        .subtitle_type(SubtitleType::Srt)
        .build();

    // Create downloader
    let downloader = Ydl::new("https://www.youtube.com/watch?v=VIDEO_ID", options)?;

    // Download subtitles
    let subtitles = downloader.download().await?;

    // Process subtitles
    println!("Downloaded {} subtitle entries", subtitles.entries.len());
    for entry in &subtitles.entries {
        println!("{} --> {}: {}", entry.start, entry.end, entry.text);
    }

    // Save to file
    downloader.download_to_file("output.srt").await?;

    Ok(())
}

Supported Formats

• SRT - SubRip subtitle format
• VTT - WebVTT format
• TXT - Plain text format
• JSON - Structured JSON format
• Raw - Original XML format from YouTube

Environment Variables

• OPENAI_API_KEY - Required for blog generation feature

Project Structure

• ydl/ - Core library for YouTube subtitle downloading
• ydl-cli/ - Command-line interface
• examples/ - Example usage code

License

This project is distributed under the terms of MIT.

See LICENSE for details.

Copyright 2025 Tyr Chen