models: patch Django user-model username max_length to be 255 characters

authentic2/__init__.py

@@ -1,6 +1,35 @@
 import sys
 import os
 
-sys.path.append(os.path.join(os.path.dirname(__file__), 'vendor'))
-# The version of Authentic
 __version__ = "2.1.2"
+
+# vendor contains incorporated dependencies
+sys.path.append(os.path.join(os.path.dirname(__file__), 'vendor'))
+
+
+# Patch base usermodel username max_lenght
+from django.utils.translation import ugettext_lazy as _
+from django.core.validators import MaxLengthValidator
+from django.db.models.signals import class_prepared
+
+MAX_USERNAME_LENGTH = 255
+
+def longer_username_signal(sender, *args, **kwargs):
+    if (sender.__name__ == "User" and
+        sender.__module__ == "django.contrib.auth.models"):
+        patch_user_model(sender)
+class_prepared.connect(longer_username_signal)
+
+def patch_user_model(model):
+    field = model._meta.get_field("username")
+
+    field.max_length = MAX_USERNAME_LENGTH
+    field.help_text = _("Required, %s characters or fewer. Only letters, "
+                        "numbers, and @, ., +, -, or _ "
+                        "characters." % MAX_USERNAME_LENGTH)
+
+    # patch model field validator because validator doesn't change if we change
+    # max_length
+    for v in field.validators:
+        if isinstance(v, MaxLengthValidator):
+            v.limit_value = MAX_USERNAME_LENGTH