youtube_transcript_api

Complete Dart port of youtube-transcript-api

• InnerTube API integration
• Multi-language & translation support
• 5 formatters (Text, JSON, VTT, SRT, CSV)
• Proxy support
• CLI tool
• 32 tests passing

🎉 Initial Release

A complete Dart port of the Python youtube-transcript-api library with enhanced features.

Added

Core Functionality

• 🎯 Fetch YouTube transcripts for any video without API keys
• 📝 Support for both manually created and auto-generated subtitles
• 🌍 Multiple language support with intelligent fallback
• 🔄 Translation support for available transcripts
• 🔍 List all available transcripts for a video
• 🎭 Filter by manually created or auto-generated transcripts

Output Formatters

• 📄 Plain text (with and without timestamps)
• 📊 JSON (simple and with full metadata)
• 📺 WebVTT (.vtt) - Standard web video format
• 🎬 SubRip (.srt) - Universal subtitle format
• 📋 CSV (.csv) - Spreadsheet-compatible format
• 🔧 Extensible formatter system for custom formats

Advanced Features

• 🔐 InnerTube API Integration - Bypasses YouTube's PoToken protection
• 🤖 Android client emulation for improved reliability
• 🌐 Proxy support:
  • Generic HTTP/HTTPS proxy configuration
  • Webshare rotating residential proxy integration
  • Custom headers and timeout configuration
• 🔄 Automatic retry logic for blocked requests
• 🚫 Comprehensive error handling with specific exceptions

Developer Experience

• 🎨 Null-safe, modern Dart implementation
• 📦 Clean, type-safe API design
• ⚡ Async/await throughout
• 🔁 Iterator interface for FetchedTranscript
• 🛠️ Extensive documentation and examples
• ✅ Comprehensive test suite (32 tests, 100% passing)
• 🔍 Detailed error messages with context

CLI Tool

• 💻 Full-featured command-line interface
• 📥 Multiple input/output formats
• 📁 File export support
• 🗂️ List available transcripts from terminal

Platform Support

• ✅ Dart CLI applications
• ✅ Flutter mobile apps (iOS & Android)
• ✅ Flutter web applications
• ✅ Flutter desktop (Windows, macOS, Linux)

Technical Highlights

• 🏗️ Architecture: Clean separation of concerns with dedicated modules for HTTP, parsing, formatting, and models
• 🔒 Security: Uses defusedxml principles for safe XML parsing
• 🎯 Reliability: InnerTube API ensures consistent access even to protected videos
• 📈 Performance: Efficient parsing with minimal memory footprint
• 🧪 Quality: 100% of core functionality covered by tests

Compatibility

• Dart SDK: >=3.0.0 <4.0.0
• Python Library Compatibility: Feature parity with youtube-transcript-api v1.2.3
• YouTube API: Uses official InnerTube API (same as YouTube mobile apps)