Fixes IPv6 detection from headers (#14456)

* fixes client ip detection for v6

* adds test for get_client_ip

* Employ urlparse() to strip port numbers from IPs

---------

Co-authored-by: Jeremy Stretch <jstretch@netboxlabs.com>

netbox/utilities/request.py

@@ -1,4 +1,5 @@
-from netaddr import IPAddress
+from netaddr import AddrFormatError, IPAddress
+from urllib.parse import urlparse
 
 __all__ = (
     'get_client_ip',
@@ -17,11 +18,18 @@ def get_client_ip(request, additional_headers=()):
     )
     for header in HTTP_HEADERS:
         if header in request.META:
-            client_ip = request.META[header].split(',')[0].partition(':')[0]
+            ip = request.META[header].split(',')[0].strip()
             try:
-                return IPAddress(client_ip)
-            except ValueError:
-                raise ValueError(f"Invalid IP address set for {header}: {client_ip}")
+                return IPAddress(ip)
+            except AddrFormatError:
+                # Parse the string with urlparse() to remove port number or any other cruft
+                ip = urlparse(f'//{ip}').hostname
+
+            try:
+                return IPAddress(ip)
+            except AddrFormatError:
+                # We did our best
+                raise ValueError(f"Invalid IP address set for {header}: {ip}")
 
     # Could not determine the client IP address from request headers
     return None