From 3c5180439a21c9cea35c41e25efc6d317a457e08 Mon Sep 17 00:00:00 2001
From: Oliver Papst <oliver.papst@mailbox.org>
Date: Tue, 4 Jan 2022 11:08:14 +0100
Subject: [PATCH] Print IPv6 url as hostname or enclosed in brackets

* Display hostname instead of ::

* Enclose literal IPv6 addresses in square brackets, e.g. [::1], to
  separate from port number
---
 jupyter_server/serverapp.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/jupyter_server/serverapp.py b/jupyter_server/serverapp.py
index 6624d043ef..51ebd23f3e 100644
--- a/jupyter_server/serverapp.py
+++ b/jupyter_server/serverapp.py
@@ -1900,10 +1900,10 @@ def _get_urlparts(self, path=None, include_token=False):
             netloc = urlencode_unix_socket_path(self.sock)
         else:
             # Handle nonexplicit hostname.
-            if self.ip in ("", "0.0.0.0"):
+            if self.ip in ("", "0.0.0.0", "::"):
                 ip = "%s" % socket.gethostname()
             else:
-                ip = self.ip
+                ip = "[{}]".format(self.ip) if ":" in self.ip else self.ip
             netloc = "{ip}:{port}".format(ip=ip, port=self.port)
             if self.certfile:
                 scheme = "https"