check email toxic domain at model-level

antispam/models/fields.py

@@ -0,0 +1,21 @@
+from django.conf import settings
+from django.db import models
+
+from antispam import forms
+
+
+class AntiSpamEmailField(models.EmailField):
+    """An email field that forbids email addresses with a known toxic domain."""
+
+    default_validators = [forms.validate_antispam_email]
+
+
+if settings.TESTING:
+    from model_bakery import baker
+
+    baker.generators.add(
+        AntiSpamEmailField, lambda: baker.random_gen.gen_email(max_length=100)
+    )
+else:  # pragma: no cover
+    # baker is only used in tests, so we don't need coverage for this part
+    pass