fix(api): Fix MultipleChoiceField custom error message (#53184)

Author: dashed

src/sentry/api/fields/multiplechoice.py

@@ -1,11 +1,11 @@
 from rest_framework import serializers
 
+ERROR_MESSAGES = {
+    "invalid_choice": ("Select a valid choice. {value} is not one of " "the available choices.")
+}
 
-class MultipleChoiceField(serializers.Field):
-    error_messages = {
-        "invalid_choice": ("Select a valid choice. {value} is not one of " "the available choices.")
-    }
 
+class MultipleChoiceField(serializers.Field):
     def __init__(self, choices=None, *args, **kwargs):
         self.choices = set(choices or ())
         super().__init__(*args, **kwargs)
@@ -18,7 +18,7 @@ def to_internal_value(self, data):
             for item in data:
                 if item not in self.choices:
                     raise serializers.ValidationError(
-                        self.error_messages["invalid_choice"].format(value=item)
+                        ERROR_MESSAGES["invalid_choice"].format(value=item)
                     )
             return data
         raise serializers.ValidationError("Please provide a valid list.")

tests/sentry/api/endpoints/test_api_tokens.py

@@ -60,6 +60,20 @@ def test_never_cache(self):
             == "max-age=0, no-cache, no-store, must-revalidate, private"
         )
 
+    def test_invalid_choice(self):
+        self.login_as(self.user)
+        url = reverse("sentry-api-0-api-tokens")
+        response = self.client.post(
+            url,
+            data={
+                "scopes": [
+                    "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua."
+                ]
+            },
+        )
+        assert response.status_code == 400
+        assert not ApiToken.objects.filter(user=self.user).exists()
+
 
 @control_silo_test(stable=True)
 class ApiTokensDeleteTest(APITestCase):