feat(auth): implement redirect to login page and save current endpoint to session

* Redirect users to the login page when authentication is required.
* Save the current endpoint in the session for post-login redirection.

1 files changed, 16 insertions, 5 deletions

diff --git a/gn2/wqflask/oauth2/checks.py b/gn2/wqflask/oauth2/checks.py
index 944760ad..6e90e7a3 100644
--- a/gn2/wqflask/oauth2/checks.py
+++ b/gn2/wqflask/oauth2/checks.py
@@ -2,7 +2,7 @@
 from functools import wraps
 from urllib.parse import urljoin
 
-from flask import flash, request, redirect
+from flask import flash, request, redirect, url_for
 from authlib.integrations.requests_client import OAuth2Session
 
 from . import session
@@ -20,10 +20,21 @@ def require_oauth2(func):
     @wraps(func)
     def __token_valid__(*args, **kwargs):
         """Check that the user is logged in and their token is valid."""
-
         def __clear_session__(_no_token):
             session.clear_session_info()
-            # redirect to the login page
+            flash("You need to be logged in.", "alert-warning")
+            return redirect("/")
+
+        def __redirect_to_login__(_token):
+            """
+            Save the current user request to session then
+            redirect to the login page.
+            """
+            if request.method == "GET":
+                redirect_url = url_for(request.endpoint, **request.args)
+            else:
+                redirect_url = "/"
+            session.set_redirect_url(redirect_url, **request.args)
             return redirect(authserver_authorise_uri())
 
         def __with_token__(token):
@@ -33,9 +44,9 @@ def require_oauth2(func):
             if not user_details.get("error", False):
                 return func(*args, **kwargs)
 
-            return __clear_session__(token)
+            return __redirect_to_login__(token)
 
-        return session.user_token().either(__clear_session__, __with_token__)
+        return session.user_token().either(__redirect_to_login__, __with_token__)
 
     return __token_valid__