Move EthnicityResponse to its own model

Author: Themitchell

lung_cancer_screening/questions/forms/ethnicity_form.py

@@ -1,15 +1,15 @@
 from django import forms
 
 from ...nhsuk_forms.choice_field import ChoiceField
-from ..models.response_set import ResponseSet, EthnicityValues
+from ..models.ethnicity_response import EthnicityResponse, EthnicityValues
 
 
 class EthnicityForm(forms.ModelForm):
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
 
-        self.fields["ethnicity"] = ChoiceField(
+        self.fields["value"] = ChoiceField(
             choices=EthnicityValues.choices,
             label="What is your ethnic background?",
             widget=forms.RadioSelect,
@@ -24,10 +24,10 @@ def __init__(self, *args, **kwargs):
             }
         )
 
-        self["ethnicity"].add_divider_after(
+        self["value"].add_divider_after(
             EthnicityValues.OTHER.value, "or"
         )
 
     class Meta:
-        model = ResponseSet
-        fields = ['ethnicity']
+        model = EthnicityResponse
+        fields = ['value']

lung_cancer_screening/questions/migrations/0028_ethnicityresponse.py

@@ -0,0 +1,53 @@
+# Generated manually to create EthnicityResponse and copy data
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+def copy_ethnicity_data(apps, schema_editor):
+    with schema_editor.connection.cursor() as cursor:
+        cursor.execute("""
+            INSERT INTO questions_ethnicityresponse (created_at, updated_at, value, response_set_id)
+            SELECT NOW(), NOW(), ethnicity, id
+            FROM questions_responseset
+            WHERE ethnicity IS NOT NULL
+            ON CONFLICT (response_set_id) DO NOTHING
+        """)
+
+
+def reverse_copy_ethnicity_data(apps, schema_editor):
+    with schema_editor.connection.cursor() as cursor:
+        cursor.execute("""
+            UPDATE questions_responseset rs
+            SET ethnicity = e.value
+            FROM questions_ethnicityresponse e
+            WHERE rs.id = e.response_set_id
+        """)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('questions', '0027_dateofbirthresponse'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='EthnicityResponse',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('updated_at', models.DateTimeField(auto_now=True)),
+                ('value', models.CharField(choices=[('A', 'Asian or Asian British'), ('B', 'Black, African, Caribbean or Black British'), ('M', 'Mixed or multiple ethnic groups'), ('W', 'White'), ('O', 'Other ethnic group'), ('N', "I'd prefer not to say")], max_length=1)),
+                ('response_set', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='ethnicity_response', to='questions.responseset')),
+            ],
+            options={
+                'abstract': False,
+            },
+        ),
+        migrations.RunPython(copy_ethnicity_data, reverse_copy_ethnicity_data),
+        migrations.RemoveField(
+            model_name='responseset',
+            name='ethnicity',
+        ),
+    ]

lung_cancer_screening/questions/models/__init__.py

@@ -3,3 +3,4 @@
 from .have_you_ever_smoked_response import HaveYouEverSmokedResponse # noqa: F401
 from .asbestos_exposure_response import AsbestosExposureResponse # noqa: F401
 from .date_of_birth_response import DateOfBirthResponse # noqa: F401
+from .ethnicity_response import EthnicityResponse # noqa: F401

lung_cancer_screening/questions/models/ethnicity_response.py

@@ -0,0 +1,18 @@
+from django.db import models
+
+from .base import BaseModel
+from .response_set import ResponseSet
+
+
+class EthnicityValues(models.TextChoices):
+    ASIAN = "A", "Asian or Asian British"
+    BLACK = "B", "Black, African, Caribbean or Black British"
+    MIXED = "M", "Mixed or multiple ethnic groups"
+    WHITE = "W", "White"
+    OTHER = "O", "Other ethnic group"
+    PREFER_NOT_TO_SAY = "N", "I'd prefer not to say"
+
+
+class EthnicityResponse(BaseModel):
+    response_set = models.OneToOneField(ResponseSet, on_delete=models.CASCADE, related_name='ethnicity_response')
+    value = models.CharField(max_length=1, choices=EthnicityValues.choices)

lung_cancer_screening/questions/tests/unit/forms/test_ethnicity_form.py

@@ -1,50 +1,53 @@
 from django.test import TestCase
 
-from ...factories.user_factory import UserFactory
-from ....models.response_set import ResponseSet, EthnicityValues
+from ...factories.response_set_factory import ResponseSetFactory
+from ....models.ethnicity_response import EthnicityResponse, EthnicityValues
 from ....forms.ethnicity_form import EthnicityForm
 
 
 class TestEthnicityForm(TestCase):
     def setUp(self):
-        self.user = UserFactory()
-        self.response_set = ResponseSet(user=self.user)
+        self.response_set = ResponseSetFactory()
+        self.response = EthnicityResponse.objects.create(
+            response_set=self.response_set,
+            value=EthnicityValues.WHITE
+        )
 
     def test_is_valid_with_a_valid_value(self):
         form = EthnicityForm(
-            instance=self.response_set,
+            instance=self.response,
             data={
-                'ethnicity': EthnicityValues.WHITE
+                'value': EthnicityValues.WHITE
             }
         )
         self.assertTrue(form.is_valid())
         self.assertEqual(
-            form.cleaned_data['ethnicity'],
+            form.cleaned_data['value'],
             EthnicityValues.WHITE
         )
 
     def test_is_invalid_with_an_invalid_value(self):
         form = EthnicityForm(
-            instance=self.response_set,
+            instance=self.response,
             data={
-                "ethnicity": "invalid"
+                "value": "invalid"
             }
         )
         self.assertFalse(form.is_valid())
         self.assertEqual(
-            form.errors["ethnicity"],
+            form.errors["value"],
             ["Select a valid choice. invalid is not one of the available choices."]
         )
 
     def test_is_invalid_when_no_option_is_selected(self):
         form = EthnicityForm(
-            instance=self.response_set,
+            instance=self.response,
             data={
-                "ethnicity": None
+                "value": None
             }
         )
         self.assertFalse(form.is_valid())
         self.assertEqual(
-            form.errors["ethnicity"],
+            form.errors["value"],
             ["Select your ethnic background"]
         )

lung_cancer_screening/questions/tests/unit/models/test_ethnicity_response.py

@@ -0,0 +1,24 @@
+from django.test import TestCase
+
+from ...factories.response_set_factory import ResponseSetFactory
+from ....models.ethnicity_response import EthnicityResponse, EthnicityValues
+
+
+class TestEthnicityResponse(TestCase):
+    def test_has_response_set_as_foreign_key(self):
+        response_set = ResponseSetFactory()
+        response = EthnicityResponse.objects.create(
+            response_set=response_set,
+            value=EthnicityValues.WHITE
+        )
+
+        self.assertEqual(response.response_set, response_set)
+
+    def test_has_value_as_string(self):
+        response_set = ResponseSetFactory()
+        response = EthnicityResponse.objects.create(
+            response_set=response_set,
+            value=EthnicityValues.WHITE
+        )
+
+        self.assertIsInstance(response.value, str)

lung_cancer_screening/questions/tests/unit/views/test_ethnicity.py

@@ -4,9 +4,7 @@
 from django.utils import timezone
 
 from .helpers.authentication import login_user
-from lung_cancer_screening.questions.models.response_set import (
-    EthnicityValues
-)
+from lung_cancer_screening.questions.models.ethnicity_response import EthnicityResponse, EthnicityValues
 
 
 class TestGetEthnicity(TestCase):
@@ -54,7 +52,7 @@ class TestPostEthnicity(TestCase):
     def setUp(self):
         self.user = login_user(self.client)
 
-        self.valid_params = {"ethnicity": EthnicityValues.WHITE}
+        self.valid_params = {"value": EthnicityValues.WHITE}
 
     def test_post_redirects_if_the_user_is_not_logged_in(self):
         self.client.logout()
@@ -82,7 +80,7 @@ def test_post_creates_unsubmitted_response_set_when_no_response_set_exists(
         self.assertEqual(self.user.responseset_set.count(), 1)
         self.assertEqual(response_set.submitted_at, None)
         self.assertEqual(
-            response_set.ethnicity, self.valid_params["ethnicity"]
+            EthnicityResponse.objects.get(response_set=response_set).value, self.valid_params["value"]
         )
         self.assertEqual(response_set.user, self.user)
 
@@ -98,7 +96,7 @@ def test_post_updates_unsubmitted_response_set_when_one_exists(self):
         self.assertEqual(self.user.responseset_set.count(), 1)
         self.assertEqual(response_set.submitted_at, None)
         self.assertEqual(
-            response_set.ethnicity, self.valid_params["ethnicity"]
+            EthnicityResponse.objects.get(response_set=response_set).value, self.valid_params["value"]
         )
         self.assertEqual(response_set.user, self.user)
 
@@ -120,7 +118,7 @@ def test_post_creates_new_unsubmitted_response_set_when_submitted_exists_over_ye
         response_set = self.user.responseset_set.last()
         self.assertEqual(response_set.submitted_at, None)
         self.assertEqual(
-            response_set.ethnicity, self.valid_params["ethnicity"]
+            EthnicityResponse.objects.get(response_set=response_set).value, self.valid_params["value"]
         )
         self.assertEqual(response_set.user, self.user)
 
@@ -146,7 +144,7 @@ def test_post_stores_a_valid_response_for_the_user(self):
 
         response_set = self.user.responseset_set.first()
         self.assertEqual(
-            response_set.ethnicity, self.valid_params["ethnicity"]
+            EthnicityResponse.objects.get(response_set=response_set).value, self.valid_params["value"]
         )
         self.assertEqual(response_set.user, self.user)
 
@@ -161,7 +159,7 @@ def test_post_redirects_to_the_education_path(self):
     def test_post_responds_with_422_if_the_response_fails_to_create(self):
         response = self.client.post(
             reverse("questions:ethnicity"),
-            {"ethnicity": "something not in list"}
+            {"value": "something not in list"}
         )
 
         self.assertEqual(response.status_code, 422)
@@ -171,7 +169,7 @@ def test_post_renders_the_ethnicity_page_with_an_error_if_form_invalid(
     ):
         response = self.client.post(
             reverse("questions:ethnicity"),
-            {"ethnicity": "something not in list"}
+            {"value": "something not in list"}
         )
 
         self.assertContains(

lung_cancer_screening/questions/views/ethnicity.py

@@ -5,25 +5,31 @@
 
 from .mixins.ensure_response_set import EnsureResponseSet
 from ..forms.ethnicity_form import EthnicityForm
+from ..models.ethnicity_response import EthnicityResponse
 
 
 class EthnicityView(LoginRequiredMixin, EnsureResponseSet, View):
     def get(self, request):
+        response, _ = EthnicityResponse.objects.get_or_build(
+            response_set=request.response_set
+        )
         return render_template(
             request,
-            EthnicityForm(instance=request.response_set)
+            EthnicityForm(instance=response)
         )
 
     def post(self, request):
+        response, _ = EthnicityResponse.objects.get_or_build(
+            response_set=request.response_set
+        )
         form = EthnicityForm(
-            instance=request.response_set,
+            instance=response,
             data=request.POST
         )
 
         if form.is_valid():
-            response_set = request.response_set
-            response_set.ethnicity = form.cleaned_data["ethnicity"]
-            response_set.save()
+            response.value = form.cleaned_data["value"]
+            response.save()
             return redirect(reverse("questions:education"))
         else:
             return render_template(