From bc71ad6d737f29a46d0a199638db2eea3ad6f71d Mon Sep 17 00:00:00 2001
From: Erik Sundell <erik.i.sundell@gmail.com>
Date: Thu, 26 Aug 2021 03:32:55 +0200
Subject: [PATCH] Apply suggestions from code review

Co-authored-by: Carol Willing <carolcode@willingconsulting.com>
---
 jupyterhub/apihandlers/users.py | 2 +-
 jupyterhub/handlers/base.py     | 2 +-
 jupyterhub/objects.py           | 4 +++-
 jupyterhub/orm.py               | 4 +---
 4 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/jupyterhub/apihandlers/users.py b/jupyterhub/apihandlers/users.py
index bc12db6c..fb480df8 100644
--- a/jupyterhub/apihandlers/users.py
+++ b/jupyterhub/apihandlers/users.py
@@ -210,7 +210,7 @@ class UserListAPIHandler(APIHandler):
             except Exception as e:
                 self.log.error("Failed to create user: %s" % name, exc_info=True)
                 self.users.delete(user)
-                raise web.HTTPError(400, f"Failed to create user {name}: {str(e)}")
+                raise web.HTTPError(400, f"Failed to create user {name}: {e}")
             else:
                 created.append(user)
 
diff --git a/jupyterhub/handlers/base.py b/jupyterhub/handlers/base.py
index 822440fa..7654d5b5 100644
--- a/jupyterhub/handlers/base.py
+++ b/jupyterhub/handlers/base.py
@@ -623,7 +623,7 @@ class BaseHandler(RequestHandler):
         if (next_url + '/').startswith(
             (
                 f'{self.request.protocol}://{self.request.host}/',
-                '//%s/' % self.request.host,
+                f'//{self.request.host}/',
             )
         ) or (
             self.subdomain_host
diff --git a/jupyterhub/objects.py b/jupyterhub/objects.py
index b6857b0b..f5893a3e 100644
--- a/jupyterhub/objects.py
+++ b/jupyterhub/objects.py
@@ -148,7 +148,9 @@ class Server(HasTraits):
     def host(self):
         if self.connect_url:
             parsed = urlparse(self.connect_url)
-            return f"{parsed.scheme}://{parsed.netloc}"
+            proto = parsed.scheme
+            host = parsed.netloc
+            return f"{proto}://{host}"
 
         if ':' in self._connect_ip:
             fmt = "{proto}://[{ip}]:{port}"
diff --git a/jupyterhub/orm.py b/jupyterhub/orm.py
index 903c544c..c368bce4 100644
--- a/jupyterhub/orm.py
+++ b/jupyterhub/orm.py
@@ -1039,8 +1039,6 @@ def get_class(resource_name):
     }
     if resource_name not in class_dict:
         raise ValueError(
-            "Kind must be one of {}, not {}".format(
-                ", ".join(class_dict), resource_name
-            )
+            f'Kind must be one of {", ".join(class_dict)}, not {resource_name}'
         )
     return class_dict[resource_name]