feat(be): implement forum-answer-upvote and downvote (#662)

* feat(be): add upvote and downvote functionality for forum answers with serializers and views

* feat(be): update is_upvoted and is_downvoted for forum-answers

* test(be): implement unit and integration tests for forum-answer upvote and downvote

* test(be): remove print statements from forum answer upvote tests

backend/core/migrations/0007_forumanswerdownvote_forumanswerupvote.py

@@ -0,0 +1,41 @@
+# Generated by Django 5.1.2 on 2024-11-19 11:34
+
+import django.db.models.deletion
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0006_alter_forumdownvote_forum_question_and_more'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='ForumAnswerDownvote',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('forum_answer', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='downvotes', to='core.forumanswer')),
+                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
+            ],
+            options={
+                'ordering': ['-created_at'],
+                'unique_together': {('user', 'forum_answer')},
+            },
+        ),
+        migrations.CreateModel(
+            name='ForumAnswerUpvote',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('forum_answer', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='upvotes', to='core.forumanswer')),
+                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
+            ],
+            options={
+                'ordering': ['-created_at'],
+                'unique_together': {('user', 'forum_answer')},
+            },
+        ),
+    ]

backend/core/models.py

@@ -160,4 +160,36 @@ class ForumAnswer(models.Model):
     created_at = models.DateTimeField(auto_now_add=True)
 
     def __str__(self):
-        return self.answer
+        return self.answer
+
+class ForumAnswerUpvote(models.Model):
+    user = models.ForeignKey(CustomUser, on_delete=models.CASCADE)
+    forum_answer = models.ForeignKey(ForumAnswer, on_delete=models.CASCADE, related_name='upvotes')
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        unique_together = ("user", "forum_answer")
+        ordering = ["-created_at"]
+
+    def save(self, *args, **kwargs):
+        ForumAnswerDownvote.objects.filter(user=self.user, forum_answer=self.forum_answer).delete()
+        super().save(*args, **kwargs)
+
+    def __str__(self):
+        return f"{self.user} upvoted {self.forum_answer}"
+
+class ForumAnswerDownvote(models.Model):
+    user = models.ForeignKey(CustomUser, on_delete=models.CASCADE)
+    forum_answer = models.ForeignKey(ForumAnswer, on_delete=models.CASCADE, related_name='downvotes')
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        unique_together = ("user", "forum_answer")
+        ordering = ["-created_at"]
+
+    def save(self, *args, **kwargs):
+        ForumAnswerUpvote.objects.filter(user=self.user, forum_answer=self.forum_answer).delete()
+        super().save(*args, **kwargs)
+
+    def __str__(self):
+        return f"{self.user} downvoted {self.forum_answer}"

backend/core/serializers/forum_vote_serializer.py

@@ -2,7 +2,7 @@
 from faker import Faker
 from rest_framework import serializers
 
-from ..models import (ForumUpvote, ForumDownvote)
+from ..models import (ForumUpvote, ForumDownvote, ForumAnswerUpvote, ForumAnswerDownvote)
 
 User = get_user_model()
 queryset = User.objects.all()
@@ -38,3 +38,33 @@ def validate(self, attrs):
             raise serializers.ValidationError("You have already downvoted this forum question.")
 
         return attrs
+
+class ForumAnswerUpvoteSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = ForumAnswerUpvote
+        fields = ("id", "user", "forum_answer", "created_at")
+        read_only_fields = ("id", "user", "created_at")
+
+    def validate(self, attrs):
+        user = self.context["request"].user
+        forum_answer = attrs["forum_answer"]
+
+        if ForumAnswerUpvote.objects.filter(user=user, forum_answer=forum_answer).exists():
+            raise serializers.ValidationError("You have already upvoted this forum answer.")
+
+        return attrs
+
+class ForumAnswerDownvoteSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = ForumAnswerDownvote
+        fields = ("id", "user", "forum_answer", "created_at")
+        read_only_fields = ("id", "user", "created_at")
+
+    def validate(self, attrs):
+        user = self.context["request"].user
+        forum_answer = attrs["forum_answer"]
+
+        if ForumAnswerDownvote.objects.filter(user=user, forum_answer=forum_answer).exists():
+            raise serializers.ValidationError("You have already downvoted this forum answer.")
+
+        return attrs

backend/core/serializers/serializers.py

@@ -3,7 +3,7 @@
 from rest_framework import serializers
 
 from ..models import (CustomUser, ForumQuestion, Quiz, QuizQuestion, QuizQuestionChoice, RateQuiz,
-                     Tag, ForumBookmark, ForumAnswer, ForumUpvote, ForumDownvote, TakeQuiz)
+                     Tag, ForumBookmark, ForumAnswer, ForumUpvote, ForumDownvote, TakeQuiz, ForumAnswerUpvote, ForumAnswerDownvote)
 from .forum_vote_serializer import ForumUpvoteSerializer, ForumDownvoteSerializer
 from .take_quiz_serializer import TakeQuizSerializer
 
@@ -50,13 +50,17 @@ class Meta:
 
 class ForumAnswerSerializer(serializers.ModelSerializer):
     author = UserInfoSerializer(read_only=True)
-    is_my_answer = serializers.SerializerMethodField()
+    upvotes_count = serializers.SerializerMethodField()
     is_upvoted = serializers.SerializerMethodField()
+    downvotes_count = serializers.SerializerMethodField()
     is_downvoted = serializers.SerializerMethodField()
+
+
     class Meta:
         model = ForumAnswer
-        fields = ('id', 'answer', 'author', 'created_at', 'is_my_answer', 'is_upvoted', 'is_downvoted')
-        read_only_fields = ('author', 'created_at')
+        fields = ('id', 'answer', 'author', 'created_at', 'upvotes_count', 'is_upvoted', 'downvotes_count', 'is_downvoted')
+        read_only_fields = ('author', 'created_at', 'upvotes_count', 'is_upvoted', 'downvotes_count', 'is_downvoted')
+
 
     def get_is_my_answer(self, obj):
         user = self.context['request'].user
@@ -81,6 +85,32 @@ def get_is_downvoted(self, obj):
     def create(self, validated_data):
         return ForumAnswer.objects.create(**validated_data)
 
+    def update(self, instance, validated_data):
+        instance.answer = validated_data.get('answer', instance.answer)
+        instance.save()
+        return instance
+
+    def get_upvotes_count(self, obj):
+        return obj.upvotes.count()
+
+    def get_is_upvoted(self, obj):
+        user = self.context['request'].user
+        if not user.is_authenticated:
+            return None
+        upvote = ForumAnswerUpvote.objects.filter(user=user, forum_answer=obj).first()
+        return upvote.id if upvote else None
+
+    def get_downvotes_count(self, obj):
+        return obj.downvotes.count()
+
+    def get_is_downvoted(self, obj):
+        user = self.context['request'].user
+        if not user.is_authenticated:
+            return False
+        downvote = ForumAnswerDownvote.objects.filter(user=user, forum_answer=obj).first()
+        return downvote.id if downvote else None
+
+
 class ForumQuestionSerializer(serializers.ModelSerializer):
     tags = TagSerializer(many=True)  # For nested representation of tags
     author = UserInfoSerializer(read_only=True)

backend/core/tests/test_forum_upvote_downvote.py

@@ -3,14 +3,13 @@
 from django.urls import reverse
 from rest_framework_simplejwt.tokens import RefreshToken
 from faker import Faker
-from core.models import ForumUpvote, ForumDownvote, ForumQuestion
+from core.models import ForumUpvote, ForumDownvote, ForumQuestion, ForumAnswer, ForumAnswerUpvote, ForumAnswerDownvote
 from django.contrib.auth import get_user_model
 
 User = get_user_model()
 fake = Faker()
 
-
-class ForumUpvoteAPITest(APITestCase):
+class ForumSetup(APITestCase):
     def setUp(self):
         # Create a test user
         self.user = User.objects.create_user(
@@ -26,24 +25,27 @@ def setUp(self):
         self.client.credentials(HTTP_AUTHORIZATION=f'Bearer {str(refresh.access_token)}')
 
         # Create a ForumQuestion
-        # self.forum_question = ForumQuestion.objects.create(
-        #     title="Test Forum Question",
-        #     question="This is a test question for votes.",
-        #     author=self.user
-        # )
-        self.forum_question_response = self.client.post(reverse('forum-question-list'), {
-            "title": "Test Forum Question",
-            "question": "This is a test question for votes.",
-            "tags": [
-                {"name": "Django", "linked_data_id": "123", "description": "A web framework."},
-                {"name": "DRF", "linked_data_id": "456", "description": "Django Rest Framework."}
-            ]
-        }, format='json').data
-
+        self.forum_question = ForumQuestion.objects.create(
+            title="Test Forum Question",
+            question="This is a test question for votes.",
+            author=self.user
+        )
 
         self.forum_question = ForumQuestion.objects.get(title='Test Forum Question')
         # Vote data
-        self.data = {"forum_question": self.forum_question.id}  
+        self.data = {"forum_question": self.forum_question.id} 
+
+        # Create a ForumAnswer
+        self.forum_answer = ForumAnswer.objects.create(
+            forum_question=self.forum_question,
+            author=self.user,
+            answer="This is a test answer for votes."
+        ) 
+        response = self.client.get(reverse('forum-question-answers-list', args=[self.forum_question.id]))
+        self.forum_answer = response.data['results'][0]
+
+
+class ForumUpvoteAPITest(ForumSetup):
 
     def test_create_forum_upvote(self):
         question_response = self.client.get(reverse("forum-question-detail", args=[self.forum_question.id]))
@@ -133,30 +135,7 @@ def test_get_list_upvote_pagination(self):
         self.assertIn("created_at", response.data['results'][0])
 
 
-class ForumDownvoteAPITest(APITestCase):
-    def setUp(self):
-        # Create a test user
-        self.user = User.objects.create_user(
-            username=fake.user_name(),
-            password="testpassword",
-            email=fake.email(),
-            full_name=fake.name()
-        )
-
-        # Authenticate the test client
-        self.client = APIClient()
-        refresh = RefreshToken.for_user(self.user)
-        self.client.credentials(HTTP_AUTHORIZATION=f'Bearer {str(refresh.access_token)}')
-
-        # Create a ForumQuestion
-        self.forum_question = ForumQuestion.objects.create(
-            title="Test Forum Question",
-            question="This is a test question for votes.",
-            author=self.user
-        )
-
-        # Vote data
-        self.data = {"forum_question": self.forum_question.id}
+class ForumDownvoteAPITest(ForumSetup):
 
     def test_create_forum_downvote(self):
         """Test creating a forum downvote"""
@@ -235,4 +214,68 @@ def test_get_list_downvote_pagination(self):
         self.assertIn("user", response.data['results'][0])
         self.assertIn("forum_question", response.data['results'][0])
         self.assertIn("created_at", response.data['results'][0])
-
+
+
+class ForumAnswerUpvoteAPITest(ForumSetup):
+
+    def test_create_forum_answer_upvote(self):
+        """Test creating a forum answer upvote"""
+        upvote_count = self.forum_answer["upvotes_count"]
+
+        # Vote data
+        data = {"forum_answer": self.forum_answer["id"]}
+
+        # Send POST request to create a new vote
+        response = self.client.post(reverse('forum-answer-upvote-list'), data=data, format='json')
+
+        # Assertions
+        self.assertEqual(response.status_code, status.HTTP_201_CREATED)
+        self.assertTrue(ForumAnswerUpvote.objects.filter(user=self.user, forum_answer=self.forum_answer["id"]).exists())
+        self.assertIn("id", response.data)
+        self.assertIn("user", response.data)
+        self.assertIn("forum_answer", response.data)
+        response = self.client.get(reverse('forum-question-answers-detail', args=[self.forum_question.id, self.forum_answer["id"]]))
+        self.assertEqual(response.data["upvotes_count"], upvote_count + 1)
+
+    def test_delete_forum_answer_upvote(self):
+        """Test deleting a forum answer upvote"""
+        # Create a forum answer and upvote to delete
+        forum_answer = ForumAnswer.objects.create(
+            forum_question=self.forum_question,
+            author=self.user,
+            answer="This is a test answer for votes."
+        )
+        response = self.client.post(reverse('forum-answer-upvote-list'), {"forum_answer": forum_answer.id}, format='json')
+        self.assertEqual(response.status_code, status.HTTP_201_CREATED)
+        response_question = self.client.get(reverse("forum-question-answers-detail", args=[self.forum_question.id, forum_answer.id]))
+        upvote_count = response_question.data["upvotes_count"]
+        # Send DELETE request to remove the upvote
+        response = self.client.delete(reverse('forum-answer-upvote-detail', args=[response.data["id"]]))
+
+        # Assertions
+        self.assertEqual(response.status_code, status.HTTP_204_NO_CONTENT)
+
+        response = self.client.get(reverse("forum-question-answers-detail", args=[self.forum_question.id, forum_answer.id]))
+
+        self.assertEqual(response.data["upvotes_count"], upvote_count - 1)
+
+    def test_downvote_after_upvote(self):
+        """Test deleting a forum answer upvote"""
+        # Create a forum answer and upvote to delete
+        forum_answer = ForumAnswer.objects.create(
+            forum_question=self.forum_question,
+            author=self.user,
+            answer="This is a test answer for votes."
+        )
+        response = self.client.post(reverse('forum-answer-upvote-list'), {"forum_answer": forum_answer.id}, format='json')
+        self.assertEqual(response.status_code, status.HTTP_201_CREATED)
+        response_question = self.client.get(reverse("forum-question-answers-detail", args=[self.forum_question.id, forum_answer.id]))
+        upvote_count = response_question.data["upvotes_count"]
+        downvote_count = response_question.data["downvotes_count"]
+        # Send DELETE request to remove the upvote
+        response = self.client.post(reverse('forum-answer-downvote-list'), {"forum_answer": forum_answer.id})
+        self.assertEqual(response.status_code, status.HTTP_201_CREATED)
+        response_question = self.client.get(reverse("forum-question-answers-detail", args=[self.forum_question.id, forum_answer.id]))
+        self.assertEqual(response_question.status_code, status.HTTP_200_OK)
+        self.assertEqual(response_question.data["upvotes_count"], upvote_count - 1)
+        self.assertEqual(response_question.data["downvotes_count"], downvote_count + 1)

backend/core/urls.py

@@ -4,8 +4,7 @@
 from .views.rate_quiz_views import RateQuizViewSet
 from .views.take_quiz_views import TakeQuizViewSet
 from .views.forum_bookmark_views import ForumBookmarkViewSet
-from .views.forum_vote_views import ForumUpvoteViewSet
-from .views.forum_vote_views import ForumDownvoteViewSet
+from .views.forum_vote_views import ForumUpvoteViewSet, ForumDownvoteViewSet, ForumAnswerUpvoteViewSet, ForumAnswerDownvoteViewSet
 from rest_framework.routers import DefaultRouter
 from rest_framework_nested import routers
 from .views import views
@@ -37,6 +36,8 @@
 router.register(r'forum-bookmarks', ForumBookmarkViewSet, basename='forumbookmark')
 router.register(r'forum-upvote', ForumUpvoteViewSet, basename='forum-upvote')
 router.register(r'forum-downvote', ForumDownvoteViewSet, basename='forum-downvote')
+router.register(r'forum-answer-upvote', ForumAnswerUpvoteViewSet, basename='forum-answer-upvote')
+router.register(r'forum-answer-downvote', ForumAnswerDownvoteViewSet, basename='forum-answer-downvote')
 
 forum_question_router = routers.NestedDefaultRouter(router, r'forum-questions', lookup='forum_question')
 forum_question_router.register(r'answers', ForumAnswerViewSet, basename='forum-question-answers')