Initial implementation of yt-dlp HLS proxy server

- Flask app with HLS proxy routes (/hls, /player, /)
- yt-dlp integration with 365-day in-memory cache
- URL validation with allowed domains (youtube, pornhub, etc)
- HTML5 HLS player with hls.js
- Unit tests: URL validation, cache, error handling
- Integration tests: ffmpeg-generated test video, full proxy chain
- Environment-based configuration (PORT, CACHE_TTL, LOG_LEVEL)
- MIT license

utils.py

@@ -0,0 +1,71 @@
+import logging
+import os
+import re
+from urllib.parse import urlparse
+
+logger = logging.getLogger(__name__)
+
+ALLOWED_DOMAINS = os.getenv("ALLOWED_DOMAINS", "youtube.com,youtu.be,pornhub.com,xvideos.com,localhost,127.0.0.1").split(",")
+
+VALIDATION_ENABLED = os.getenv("VALIDATION_ENABLED", "true").lower() == "true"
+ALLOW_LOCAL = os.getenv("ALLOW_LOCAL", "true").lower() == "true"
+
+
+def is_valid_url(url: str) -> bool:
+    if not VALIDATION_ENABLED:
+        return True
+    
+    if not url:
+        return False
+    
+    try:
+        parsed = urlparse(url)
+        if not parsed.scheme or not parsed.netloc:
+            return False
+        
+        domain = parsed.netloc.lower()
+        if domain.startswith("www."):
+            domain = domain[4:]
+        
+        if ALLOW_LOCAL and (domain in ("localhost", "127.0.0.1") or domain.startswith("localhost:") or domain.startswith("127.0.0.1:")):
+            return True
+        
+        for allowed in ALLOWED_DOMAINS:
+            allowed = allowed.strip().lower()
+            if domain == allowed or domain.endswith(f".{allowed}"):
+                return True
+        
+        return False
+    except Exception as e:
+        logger.error(f"URL validation error: {e}")
+        return False
+
+
+def extract_video_id(url: str) -> str:
+    patterns = {
+        r'(?:youtube\.com/watch\?v=|youtu\.be/|youtube\.com/embed/)([a-zA-Z0-9_-]{11})': 'youtube',
+        r'pornhub\.com/view_video\.php\?viewkey=([a-zA-Z0-9]+)': 'pornhub',
+    }
+    
+    for pattern, platform in patterns.items():
+        match = re.search(pattern, url)
+        if match:
+            return match.group(1)
+    
+    return ""
+
+
+def sanitize_path(path: str) -> str:
+    return path.replace("..", "").replace("//", "/").strip("/")
+
+
+def get_error_message(status_code: int) -> str:
+    errors = {
+        400: "Bad Request - Invalid URL or parameters",
+        403: "Forbidden - Access denied",
+        404: "Not Found - Resource not found",
+        500: "Internal Server Error",
+        502: "Bad Gateway - Upstream error",
+        503: "Service Unavailable",
+    }
+    return errors.get(status_code, "Unknown error")