Refactoring into the factory style

done while trying to fix an unrelated error; keeping this as a
stylistic change regardless

bugsink/api_fields.py

@@ -1,17 +1,22 @@
 from rest_framework import serializers
 
 
-class EnumLowercaseChoiceField(serializers.ChoiceField):
+def make_enum_field(enum_cls, *, name=None):
 
-    def __init__(self, enum_cls, **kwargs):
-        self._to_value = {member.name.lower(): member.value for member in enum_cls}
-        super().__init__(choices=self._to_value, **kwargs)
-        self._to_name = {member.value: member.name.lower() for member in enum_cls}
+    class EnumChoiceField(serializers.ChoiceField):
+        _enum_cls = enum_cls
 
-    def to_representation(self, value):
-        # fails hard for invalid values (shouldn't happen, would imply data corruption)
-        return self._to_name[value]
+        def __init__(self, **kwargs):
+            self._to_value = {m.name.lower(): m.value for m in enum_cls}
+            self._to_name = {m.value: m.name.lower() for m in enum_cls}
+            super().__init__(choices=self._to_value, **kwargs)
 
-    def to_internal_value(self, data):
-        key = super().to_internal_value(data)
-        return self._to_value[key]
+        def to_representation(self, value):
+            return self._to_name[value]
+
+        def to_internal_value(self, data):
+            key = super().to_internal_value(data)
+            return self._to_value[key]
+
+    EnumChoiceField.__name__ = name or f"{enum_cls.__name__}Field"
+    return EnumChoiceField

projects/serializers.py

@@ -1,5 +1,5 @@
 from rest_framework import serializers
-from bugsink.api_fields import EnumLowercaseChoiceField
+from bugsink.api_fields import make_enum_field
 
 from teams.models import Team
 from bugsink.api_mixins import ExpandableSerializerMixin
@@ -8,8 +8,11 @@ from teams.serializers import TeamDetailSerializer
 from .models import Project, ProjectVisibility
 
 
+ProjectVisibilityField = make_enum_field(ProjectVisibility)
+
+
 class ProjectListSerializer(serializers.ModelSerializer):
-    visibility = EnumLowercaseChoiceField(ProjectVisibility)
+    visibility = ProjectVisibilityField()
     dsn = serializers.CharField(read_only=True)
 
     class Meta:
@@ -33,7 +36,7 @@ class ProjectListSerializer(serializers.ModelSerializer):
 
 class ProjectDetailSerializer(ExpandableSerializerMixin, serializers.ModelSerializer):
     expandable_fields = {"team": TeamDetailSerializer}
-    visibility = EnumLowercaseChoiceField(ProjectVisibility)
+    visibility = ProjectVisibilityField()
     dsn = serializers.CharField(read_only=True)
 
     class Meta:
@@ -58,7 +61,7 @@ class ProjectDetailSerializer(ExpandableSerializerMixin, serializers.ModelSerial
 class ProjectCreateUpdateSerializer(serializers.ModelSerializer):
     id = serializers.UUIDField(read_only=True)
     team = serializers.PrimaryKeyRelatedField(queryset=Team.objects.all())
-    visibility = EnumLowercaseChoiceField(ProjectVisibility, required=False)
+    visibility = ProjectVisibilityField(required=False)
 
     class Meta:
         model = Project

teams/serializers.py

@@ -1,10 +1,13 @@
 from rest_framework import serializers
-from bugsink.api_fields import EnumLowercaseChoiceField
+from bugsink.api_fields import make_enum_field
 from .models import Team, TeamVisibility
 
 
+TeamVisibilityField = make_enum_field(TeamVisibility)
+
+
 class TeamListSerializer(serializers.ModelSerializer):
-    visibility = EnumLowercaseChoiceField(TeamVisibility)
+    visibility = TeamVisibilityField()
 
     class Meta:
         model = Team
@@ -12,7 +15,7 @@ class TeamListSerializer(serializers.ModelSerializer):
 
 
 class TeamDetailSerializer(serializers.ModelSerializer):
-    visibility = EnumLowercaseChoiceField(TeamVisibility)
+    visibility = TeamVisibilityField()
 
     class Meta:
         model = Team
@@ -21,7 +24,7 @@ class TeamDetailSerializer(serializers.ModelSerializer):
 
 class TeamCreateUpdateSerializer(serializers.ModelSerializer):
     id = serializers.UUIDField(read_only=True)
-    visibility = EnumLowercaseChoiceField(TeamVisibility, required=False)
+    visibility = TeamVisibilityField(required=False)
 
     class Meta:
         model = Team