feature(like and dislike a comment): implement feature to allow likin…

…g and disliking articles

 - add feature to allow liking article comments
 - add feature to allow disliking article comments.

 [Delivers #161966629]

authors/apps/articles/exceptions.py

@@ -1,4 +1,11 @@
 from rest_framework.exceptions import NotFound
 
 class ArticleNotFound(NotFound):
-    default_detail = 'Article with this slug not found'
+    default_detail = 'Article with this slug not found'
+
+class CommentNotFound(NotFound):
+    """
+    comment id not found exception
+    """
+
+    default_detail = 'Comment ID not found.'

authors/apps/articles/extra_views.py

@@ -1,8 +1,14 @@
-from rest_framework.generics import CreateAPIView, ListAPIView
-from authors.apps.articles.models import BookMarkArticle, Article
+from rest_framework.generics import (
+    CreateAPIView, ListAPIView,
+    UpdateAPIView
+)
+from authors.apps.articles.models import (
+    BookMarkArticle, Article,
+    Comment
+)
 from rest_framework.response import Response
 from rest_framework import status
-from authors.apps.articles.exceptions import ArticleNotFound
+from authors.apps.articles.exceptions import ArticleNotFound, CommentNotFound
 from authors.apps.articles.serializers import BookMarkArticleSerializer
 
 
@@ -21,7 +27,7 @@ def post(self, request, article_slug):
         try:
             article = Article.objects.get(article_slug=article_slug)
         except Article.DoesNotExist:
-            raise ArticleNotFound()
+            raise ArticleNotFound
         bookmark, created = BookMarkArticle.objects.get_or_create(
             user=user,
             article=article
@@ -69,4 +75,53 @@ def list(self, request):
                     'message': 'No articles bookmarked yet.'
                 },
                 status=status.HTTP_200_OK
-            )
+            )
+
+class LikeComment(UpdateAPIView):
+    """Class for liking and un -liking an article"""
+
+    def update(self, request, comment_pk):
+        """This method updates the liking of an article"""
+        try:
+            comment = Comment.objects.get(id=comment_pk)
+        except Comment.DoesNotExist:
+            raise CommentNotFound
+
+        # gets the user of that specific session
+        user = request.user
+        # checks for the boolean value of liking an article
+        liked = bool(user in comment.like.all())
+        if liked is True:
+            comment.like.remove(user.id)
+            message = {"message": "You have unliked this comment"}
+            return Response(message, status.HTTP_200_OK)
+
+        # if like is false, the article is liked
+        comment.like.add(user.id)
+        message = {"message": "You have liked this comment"}
+        return Response(message, status.HTTP_200_OK)
+
+
+class DislikeComment(UpdateAPIView):
+    """Class for disliking and  un-disliking an comment"""
+
+    def update(self, request, comment_pk):
+        """This method updates the liking of an comment"""
+        LikeComment.update(self, request, comment_pk)
+        comment = Comment.objects.filter(id=comment_pk).first()
+        if comment is None:
+            raise CommentNotFound
+
+        # gets the user of that specific session
+        user = request.user
+        # checks for the boolean value of disliking an article
+        disliked = bool(user in comment.dislike.all())
+        if disliked is True:
+            comment.dislike.remove(user.id)
+            message = {"message": "This comment has been un-disliked"}
+            return Response(message, status.HTTP_200_OK)
+
+        # if disike is false, the comment is disliked
+        comment.dislike.add(user.id)
+        message = {"message": "You have disliked this comment"}
+        return Response(message, status.HTTP_200_OK)

authors/apps/articles/migrations/0004_auto_20181219_0847.py

@@ -0,0 +1,25 @@
+# Generated by Django 2.1 on 2018-12-19 08:47
+
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ('articles', '0003_auto_20181218_2105'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='comment',
+            name='dislike',
+            field=models.ManyToManyField(blank=True, related_name='dislikecomment', to=settings.AUTH_USER_MODEL),
+        ),
+        migrations.AddField(
+            model_name='comment',
+            name='like',
+            field=models.ManyToManyField(blank=True, related_name='likecomment', to=settings.AUTH_USER_MODEL),
+        ),
+    ]

authors/apps/articles/models.py

@@ -86,6 +86,7 @@ class Comment(models.Model):
         blank=False,
         null=False,
     )
+    # add like and dislike field in the comment
     article = models.ForeignKey(Article, related_name='comments', on_delete=models.CASCADE)
     author = models.ForeignKey(Profile, related_name='comments', on_delete=models.CASCADE)
     # The beginning of the highlight
@@ -94,6 +95,8 @@ class Comment(models.Model):
     highlight_end = models.IntegerField(default=-1)
     created_at = models.DateTimeField(auto_now_add=True)
     last_update = models.DateTimeField(auto_now=True)
+    like = models.ManyToManyField(User, blank=True, related_name='likecomment')
+    dislike = models.ManyToManyField(User, blank=True, related_name='dislikecomment')
 
     class Meta:
         """"

authors/apps/articles/serializers.py

@@ -136,6 +136,24 @@ class to serialize comments data
     last_update = serializers.SerializerMethodField(method_name='get_formated_last_update')
     replies = ReplySerializer(many=True, read_only=True)
 
+    def likes(self, instance):
+        """method to return a user who has liked an article"""
+        request = self.context.get('request')
+        liked = False
+        if request is not None and request.user.is_authenticated:
+            user_id = request.user.id
+            liked = instance.likes.all().filter(id=user_id).count() == 1
+        return {'likes': instance.likes.count(), 'User': liked}
+
+    def dislikes(self, instance):
+        """method to return a user who has disliked an article"""
+        request = self.context.get('request')
+        disliked = False
+        if request is not None and request.user.is_authenticated:
+            user_id = request.user.id
+            disliked = instance.dislikes.all().filter(id=user_id).count() == 1
+        return {'dislikes': instance.dislikes.count(), 'User': disliked}
+
     class Meta:
         """
         define serializer attributes
@@ -147,7 +165,9 @@ class Meta:
             'body',
             'created_at',
             'last_update',
-            'replies'
+            'replies',
+            'like',
+            'dislike'
         )
 
     def create(self, validated_data):

authors/apps/articles/tests/base_test.py

@@ -183,7 +183,33 @@ def create_comment(self, token, article_slug):
                 HTTP_AUTHORIZATION=token
             )
         return response
-
+
+    def like_comment_url(self, comment_pk):
+        """
+        return the url for liking a specific comment ID
+        """
+        return reverse('articles:like-comment', kwargs={
+            'comment_pk': comment_pk
+        })
+
+    def dislike_comment_url(self, comment_pk):
+        """
+        return the url for disking a specific comment ID
+        """
+        return reverse('articles:dislike-comment', kwargs={
+            'comment_pk': comment_pk
+        })
+
+    def get_comment_id(self):
+        """
+        return comment ID for liking and disliking a comment
+        """
+        self.user_signup()
+        token = self.user_login()
+        article_url, saved_article, token = self.create_article()
+        article_slug = saved_article.data['slug']
+        comment_response = self.create_comment(token, article_slug)
+        return comment_response.data['comment']['id'], token
 
     def create_article(self):
         """

authors/apps/articles/tests/test_liking_and_disliking_comments.py

@@ -0,0 +1,57 @@
+from rest_framework import status
+from .base_test import BaseTestCase
+from django.urls import reverse
+
+
+class TestLikingComments(BaseTestCase):
+    "class to test liking and disliking of articles"
+
+    def test_like_comment(self):
+        """test for liking a comment"""
+        comment_id, token = self.get_comment_id()
+        response = self.client.put(self.like_comment_url(comment_id), format='json', HTTP_AUTHORIZATION=token)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertEqual(response.data,  {'message': 'You have liked this comment'})
+
+    def test_dislike_comment(self):
+        """test for liking a comment"""
+        comment_id, token = self.get_comment_id()
+        response = self.client.put(self.dislike_comment_url(comment_id) , format='json', HTTP_AUTHORIZATION=token)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertEqual(response.data, {'message': "You have disliked this comment"})
+
+    def test_like_dislike_comment(self):
+        """test for liking then disliking a comment"""
+        comment_id, token = self.get_comment_id()
+        response = self.client.put(self.like_comment_url(comment_id), format='json', HTTP_AUTHORIZATION=token)
+        self.assertEqual(response.data, {'message': 'You have liked this comment'})
+        response = self.client.put(self.dislike_comment_url(comment_id), format='json', HTTP_AUTHORIZATION=token)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertEqual(response.data, {'message': "You have disliked this comment"})
+
+    def test_dislike_like_comment(self):
+        """test for liking then unliking a comment"""
+        comment_id, token = self.get_comment_id()
+        response = self.client.put(self.dislike_comment_url(comment_id), format='json', HTTP_AUTHORIZATION=token)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertEqual(response.data, {'message': "You have disliked this comment"})
+        response = self.client.put(self.like_comment_url(comment_id), format='json', HTTP_AUTHORIZATION=token)
+        self.assertEqual(response.data, {'message': 'You have unliked this comment'})
+
+    def test_like_nonexisting_comment(self):
+        """test for liking an comment"""
+        self.user_signup()
+        token = self.user_login()
+        non_existing_id = 5 # not existing comment ID
+        response = self.client.put(self.like_comment_url(non_existing_id), format='json', HTTP_AUTHORIZATION='Token ' + token)
+        self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
+        self.assertEqual(response.data, {'detail': "Comment ID not found."})
+
+    def test_dislike_nonexisting_comment(self):
+        """test for liking an comment"""
+        self.user_signup()
+        token = self.user_login()
+        non_existing_id = 5 # not existing comment ID
+        response = self.client.put(self.like_comment_url(non_existing_id), format='json', HTTP_AUTHORIZATION='Token ' + token)
+        self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
+        self.assertEqual(response.data, {'detail': "Comment ID not found."})

authors/apps/articles/urls.py

@@ -10,7 +10,9 @@
 )
 from authors.apps.articles.extra_views import (
     BookMarkCreateAPIView, 
-    BookMarkListAPIView
+    BookMarkListAPIView,
+    LikeComment,
+    DislikeComment,
 )
 
 
@@ -29,4 +31,6 @@
     path('articles/reports/', ReportListAPIView.as_view(), name='report-list'),
     path('articles/<str:article_slug>/bookmark/', BookMarkCreateAPIView.as_view(), name='bookmark-article'),
     path('articles/bookmarks/', BookMarkListAPIView.as_view(), name='get-bookmarks'),
+    path('comments/<int:comment_pk>/like/', LikeComment.as_view(), name='like-comment'),
+    path('comments/<int:comment_pk>/dislike/', DislikeComment.as_view(), name='dislike-comment'),
 ]