While you’re able to customize the error message for a unique field when defining your model…
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| class Context(models.Model): | |
| name = models.CharField(error_messages={'unique': u'My custom message'}) |
…you can’t do the same for a unique_together constraint. There’s an open ticket but it hasn’t seen much attention. In the meantime, you can override the unique_error_message in your model to provide a custom error message:
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| def unique_error_message(self, model_class, unique_check): | |
| if model_class == type(self) and unique_check == ('field1', 'field2'): | |
| return 'Your custom error message.' | |
| else: | |
| return super(YourModel, self).unique_error_message(model_class, unique_check) |
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