Display messages/notifications

[qwertycandy]

Hello, I would like some help with messages, please. I'm writing a custom validator and I need to display a warning message if for example a device name doesn't fit the company's policy. I can't use the fail method - the edit request should be fulfilled, it's just supposed to warn the user as well. I would like to use a box message like in #9650, just with the warning level.

I tried something like this:

from extras.validators import CustomValidator
from django.contrib import messages

class device_validator(CustomValidator):
	def validate(self, instance):
		if instance.name is not instance.name.upper():
			messages.warning(request, "Names of devices should be in all-caps.")		
			return

But clearly, my syntax is wrong - I get the "Server Error" window and following message:

<class 'NameError'>

name 'request' is not defined

Could someone please give me an example how to display a message in this context?
Thank you.

[jeremystretch]

I can't use the fail method - the edit request should be fulfilled, it's just supposed to warn the user as well.

The purpose of validation is to prevent an erroneous or invalid action from taking place. There is no facility in place to permit an invalid action but provide a warning, as that would be of extremely limited utility. Instead, you might consider writing a report to routinely check for non-conforming names.

[qwertycandy]

Thank you - I get that this is a bit niche, but it would really help me to be able to use messages in reports. For example when user adds/edits a device that has no IP address assigned to it - I would like to display a warning message there, as perhaps they just forgot to assign it (and it that case a mistake could be caught immediatelly), but it could also be legitimate.
Is there a way to refference/display messages within a validator, please, or is that technically impossible?

[kkthxbye-code]

Unrelated to your issue but this will not work:

if instance.name is not instance.name.upper():

The is keyword compares identity, you want to use != instead which compares value.