Initial LinkLog implementation

backend/app/core/security.py

@@ -0,0 +1,25 @@
+from datetime import datetime, timedelta, timezone
+from hashlib import sha256
+
+from backend.app.core.config import settings
+
+
+def hash_token(token: str) -> str:
+    return sha256(token.encode('utf-8')).hexdigest()
+
+
+def token_expires_at() -> datetime:
+    return datetime.now(timezone.utc) + timedelta(days=settings.token_expiry_days)
+
+
+def clean_url(url: str) -> str:
+    from urllib.parse import parse_qsl, urlsplit, urlunsplit
+
+    parts = urlsplit(url)
+    if not parts.query:
+        return url
+
+    params = parse_qsl(parts.query, keep_blank_values=True)
+    filtered = [(k, v) for k, v in params if k not in settings.tracking_params]
+    new_query = '&'.join(f'{k}={v}' if v != '' else k for k, v in filtered)
+    return urlunsplit((parts.scheme, parts.netloc, parts.path, new_query, parts.fragment))