implement authentication redirect

atst/domain/auth.py

@@ -0,0 +1,18 @@
+from functools import wraps
+from flask import g, request, redirect, url_for, session
+
+from atst.domain.users import Users
+
+
+def login_required(f):
+
+    @wraps(f)
+    def decorated_function(*args, **kwargs):
+        if session.get("user_id"):
+            g.user = Users.get(session.get("user_id"))
+            return f(*args, **kwargs)
+
+        else:
+            return redirect(url_for("atst.root"))
+
+    return decorated_function