"""
URL utility functions for YouTube URLs.
"""
import re
from urllib.parse import urlparse, parse_qs
from typing import Optional
def extract_video_id(url: str) -> Optional[str]:
"""
Extract video ID from various YouTube URL formats.
Args:
url: YouTube URL
Returns:
Video ID or None if not found
"""
# Regular expressions for different YouTube URL formats
patterns = [
r'(?:youtube\.com\/watch\?v=|youtu\.be\/|youtube\.com\/embed\/)([a-zA-Z0-9_-]{11})',
r'youtube\.com\/v\/([a-zA-Z0-9_-]{11})',
r'youtube\.com\/watch\?.*v=([a-zA-Z0-9_-]{11})',
]
for pattern in patterns:
match = re.search(pattern, url)
if match:
return match.group(1)
return None
def is_valid_youtube_url(url: str) -> bool:
"""
Check if URL is a valid YouTube URL.
Args:
url: URL to validate
Returns:
True if valid YouTube URL
"""
try:
parsed = urlparse(url)
valid_domains = [
"youtube.com",
"www.youtube.com",
"youtu.be",
"m.youtube.com"
]
return parsed.netloc in valid_domains
except Exception:
return False
def normalize_youtube_url(url: str) -> Optional[str]:
"""
Normalize YouTube URL to standard format.
Args:
url: YouTube URL to normalize
Returns:
Normalized URL or None if invalid
"""
video_id = extract_video_id(url)
if video_id:
return f"https://www.youtube.com/watch?v={video_id}"
return None
def extract_playlist_id(url: str) -> Optional[str]:
"""
Extract playlist ID from YouTube URL.
Args:
url: YouTube playlist URL
Returns:
Playlist ID or None if not found
"""
try:
parsed = urlparse(url)
query_params = parse_qs(parsed.query)
if 'list' in query_params:
return query_params['list'][0]
except Exception:
pass
return None
def extract_channel_id(url: str) -> Optional[str]:
"""
Extract channel ID from YouTube URL.
Args:
url: YouTube channel URL
Returns:
Channel ID or None if not found
"""
patterns = [
r'youtube\.com\/channel\/([a-zA-Z0-9_-]+)',
r'youtube\.com\/c\/([a-zA-Z0-9_-]+)',
r'youtube\.com\/@([a-zA-Z0-9_-]+)',
r'youtube\.com\/user\/([a-zA-Z0-9_-]+)',
]
for pattern in patterns:
match = re.search(pattern, url)
if match:
return match.group(1)
return None
def normalize_channel_url(url: str) -> Optional[str]:
"""
Normalize YouTube channel URL to modern @handle format.
Converts various channel URL formats to the modern @handle format:
- youtube.com/ChannelName -> youtube.com/@ChannelName
- youtube.com/c/ChannelName -> youtube.com/@ChannelName
- youtube.com/user/ChannelName -> youtube.com/@ChannelName
- youtube.com/channel/UCxxx -> youtube.com/channel/UCxxx (keep channel ID format)
Args:
url: YouTube channel URL to normalize
Returns:
Normalized channel URL or original URL if no normalization needed
"""
if not is_valid_youtube_url(url):
return None
# Pattern to match old-style channel URLs without @ symbol
# Matches: youtube.com/ChannelName (but not youtube.com/@ChannelName, youtube.com/watch, etc.)
old_format_pattern = r'(https?://)?(www\.)?youtube\.com/([a-zA-Z0-9_-]+)(?:/.*)?$'
match = re.match(old_format_pattern, url)
if match:
channel_name = match.group(3)
# Don't convert if it's already a known path (watch, playlist, etc.) or starts with UC (channel ID)
if channel_name not in ['watch', 'playlist', 'embed', 'v', 'shorts', 'live', 'channel', 'c', 'user'] and not channel_name.startswith('UC'):
return f"https://www.youtube.com/@{channel_name}"
# Handle /c/ format
if '/c/' in url:
channel_name = extract_channel_id(url)
if channel_name:
return f"https://www.youtube.com/@{channel_name}"
# Handle /user/ format
if '/user/' in url:
channel_name = extract_channel_id(url)
if channel_name:
return f"https://www.youtube.com/@{channel_name}"
# Return original URL if no normalization needed
return url
