165305760-Feature(Rating): Users are able to rate an article

- User can rate an article
- fix codeclimate issues
- Return average ratings
- Added a standard response message

starts #165305760

authors/apps/articles/migrations/0001_initial.py

@@ -1,8 +1,7 @@
-# Generated by Django 2.2 on 2019-05-10 07:26
+# Generated by Django 2.2 on 2019-05-10 08:25
 
 import autoslug.fields
 import cloudinary.models
-from django.conf import settings
 from django.db import migrations, models
 import django.db.models.deletion
 
@@ -12,7 +11,6 @@ class Migration(migrations.Migration):
     initial = True
 
     dependencies = [
-        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
     ]
 
     operations = [
@@ -32,12 +30,17 @@ class Migration(migrations.Migration):
                 ('image', cloudinary.models.CloudinaryField(max_length=255, verbose_name='image')),
                 ('favorited', models.BooleanField(default=False)),
                 ('favoritesCount', models.PositiveSmallIntegerField(default=0)),
-                ('author', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
             ],
             options={
                 'ordering': ['created_at'],
             },
         ),
+        migrations.CreateModel(
+            name='Favorite',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+            ],
+        ),
         migrations.CreateModel(
             name='Tag',
             fields=[
@@ -49,16 +52,11 @@ class Migration(migrations.Migration):
             },
         ),
         migrations.CreateModel(
-            name='Favorite',
+            name='RatingModel',
             fields=[
                 ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('article', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='articles.Article')),
-                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
+                ('rate', models.IntegerField(default=0)),
+                ('article', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='rated_article', to='articles.Article')),
             ],
         ),
-        migrations.AddField(
-            model_name='article',
-            name='tags',
-            field=models.ManyToManyField(to='articles.Tag'),
-        ),
     ]

authors/apps/articles/migrations/0002_auto_20190510_0825.py

@@ -0,0 +1,43 @@
+# Generated by Django 2.2 on 2019-05-10 08:25
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+        ('articles', '0001_initial'),
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='ratingmodel',
+            name='rated_by',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='rated_by', to=settings.AUTH_USER_MODEL),
+        ),
+        migrations.AddField(
+            model_name='favorite',
+            name='article',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='articles.Article'),
+        ),
+        migrations.AddField(
+            model_name='favorite',
+            name='user',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL),
+        ),
+        migrations.AddField(
+            model_name='article',
+            name='author',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL),
+        ),
+        migrations.AddField(
+            model_name='article',
+            name='tags',
+            field=models.ManyToManyField(to='articles.Tag'),
+        ),
+    ]

authors/apps/articles/models.py

@@ -101,3 +101,27 @@ class Favorite(models.Model):
     """
     user = models.ForeignKey(User, on_delete=models.CASCADE)
     article = models.ForeignKey(Article, on_delete=models.CASCADE)
+
+
+class RatingModel(models.Model):
+    """
+    Models for rating an article (0 - 5)
+    """
+    article = models.ForeignKey(
+        Article, related_name='rated_article', on_delete=models.CASCADE)
+    rated_by = models.ForeignKey(
+        User, related_name='rated_by', on_delete=models.CASCADE)
+    rate = models.IntegerField(default=0)
+
+    def get_articles_details(self):
+        """
+        Fetch relevant articles details
+        """
+        return {
+            "slug": self.article.slug,
+            "title": self.article.title,
+            "description": self.article.description,
+            "body": self.article.body,
+            "created_at": self.article.created_at,
+            "updated_at": self.article.updated_at
+        }

authors/apps/articles/serializers.py

@@ -1,12 +1,15 @@
-from rest_framework import serializers
-from .models import Article, Favorite
 import json
+from collections import OrderedDict
+
 from authors.apps.articles.models import Tag
+from authors.apps.utils.baseserializer import BaseSerializer
+from django.db.models import Avg
+from rest_framework import serializers
 from rest_framework.pagination import PageNumberPagination
-from collections import OrderedDict
 from rest_framework.response import Response
+
 from .exceptions import ArticleNotFound
-from authors.apps.utils.baseserializer import BaseSerializer
+from .models import Article, Favorite, RatingModel
 
 
 class ArticleSerializer(BaseSerializer):
@@ -112,3 +115,37 @@ class Meta:
         fields = (
             'user', 'article'
         )
+class RatingSerializer(ArticleSerializer):
+    """
+    Serializer class to rate an article
+    """
+
+    rated_by = serializers.ReadOnlyField()
+    article = serializers.ReadOnlyField(source='get_articles_details')
+    rate = serializers.IntegerField(
+        min_value=1,
+        max_value=5,
+        required=True
+    )
+    average_rating = serializers.SerializerMethodField(
+        method_name="calulate_average_rating"
+    )
+
+    class Meta:
+        model = RatingModel
+        fields = ('rate',
+                  'average_rating',
+                  'article',
+                  'rated_by'
+                  )
+
+    def calulate_average_rating(self, obj):
+        """
+        Calculate the average rating of an article
+        """
+        average_rate = RatingModel.objects.filter(article=obj.article,
+                                                  ).aggregate(rate=Avg('rate'))
+
+        if average_rate["rate"]:
+            return float('%.2f' % (average_rate["rate"]))
+        return 0

authors/apps/articles/tests/basetests.py

@@ -1,3 +1,5 @@
+import json
+
 from django.contrib.auth import get_user_model
 from rest_framework.test import APITestCase, APIClient
 from rest_framework.reverse import reverse
@@ -257,6 +259,76 @@ def get_favorites(self):
             content_type="application/json"
         )
 
+    def rate_article(self):
+        """
+        Pass slug to the url and post the ratings
+        """
+        slug = str(self.article.slug)
+        url = reverse("articles:rating_articles", args=[slug])
+        return self.client.post(
+            url,
+            data=json.dumps({
+                "rate": 4
+            }),
+            content_type="application/json"
+        )
+
+    def update_rate_article(self):
+        """
+        Pass slug to the url and post the ratings
+        """
+        slug = str(self.article.slug)
+        url = reverse("articles:rating_articles", args=[slug])
+        return self.client.post(
+            url,
+            data=json.dumps({
+                "rate": 3
+            }),
+            content_type="application/json"
+        )
+
+    def rate_article_more_than_five(self):
+        """
+        Pass slug to the url and post the ratings
+        """
+        slug = str(self.article.slug)
+        url = reverse("articles:rating_articles", args=[slug])
+        return self.client.post(
+            url,
+            data=json.dumps({
+                "rate": 7
+            }),
+            content_type="application/json"
+        )
+
+    def rate_article_less_than_one(self):
+        """
+        Pass slug to the url and post the ratings
+        """
+        slug = str(self.article.slug)
+        url = reverse("articles:rating_articles", args=[slug])
+        return self.client.post(
+            url,
+            data=json.dumps({
+                "rate": -1
+            }),
+            content_type="application/json"
+        )
+
+    def rate_non_existing_article(self):
+        """
+        Pass slug to the url and post the ratings
+        """
+        slug = "how-to-let-go"
+        url = reverse("articles:rating_articles", args=[slug])
+        return self.client.post(
+            url,
+            data=json.dumps({
+                "rate": 4
+            }),
+            content_type="application/json"
+        )
+
 
 class TagsBaseTest(APITestCase):
     """

authors/apps/articles/tests/test_ratings.py

@@ -0,0 +1,49 @@
+import json
+
+from rest_framework.views import status
+from .basetests import BaseTest
+
+
+class RatingArticlesTest(BaseTest):
+    """
+    Test cases for article ratings
+    """
+    unauthorized = "Authentication credentials were not provided."
+
+    def test_rate_an_article_with_authorized_user(self):
+        """
+        Test if an article is rated when no data is passed
+        """
+        rating = self.rate_article()
+        self.assertEqual(rating.status_code, status.HTTP_201_CREATED)
+
+    def test_update_ratings_on_an_article_with_authorized_user(self):
+        """
+        Test if an article is rated when no data is passed
+        """
+        rating = self.update_rate_article()
+        self.assertEqual(rating.status_code, status.HTTP_201_CREATED)
+
+
+    def test_rate_an_article_with_greater_than_five(self):
+        """
+        Test if an article is rated when the rate is more that 5
+        """
+        rating = self.rate_article_more_than_five()
+        self.assertEqual(rating.status_code, status.HTTP_400_BAD_REQUEST)
+
+
+    def test_rate_an_article_with_less_than_one(self):
+        """
+        Test if an article is rated when that rate is less than 1
+        """
+        rating = self.rate_article_less_than_one()
+        self.assertEqual(rating.status_code, status.HTTP_400_BAD_REQUEST)
+
+    def test_rate_a_non_existing_article(self):
+        """
+        Test if an article is rated when article doesn't exist
+        """
+
+        rating = self.rate_non_existing_article()
+        self.assertEqual(rating.status_code, status.HTTP_404_NOT_FOUND)

authors/apps/articles/urls.py

@@ -1,17 +1,15 @@
+from django.conf.urls import url
 from django.urls import path
-from .views import (
-    ListCreateArticleAPIView,
-    RetrieveUpdateArticleAPIView,
-    FetchTags,
-    LikeDislikeView,
-    FavoritesView,
-    ListUserFavoriteArticlesView)
+
+from .views import (FavoritesView, FetchTags, LikeDislikeView,
+                    ListCreateArticleAPIView, ListUserFavoriteArticlesView,
+                    RateArticleAPIView, RetrieveUpdateArticleAPIView)
 
 app_name = 'articles'
 
 urlpatterns = [
     path('articles/', ListCreateArticleAPIView.as_view(), name='article'),
-    path('articles/<slug>/', RetrieveUpdateArticleAPIView.as_view(),
+    path('articles/<slug>', RetrieveUpdateArticleAPIView.as_view(),
          name='articles'),
     path('tags/', FetchTags.as_view(), name="all_tags"),
     path('articles/<str:slug>/<str:vote_type>/vote/',
@@ -20,4 +18,6 @@
          FavoritesView.as_view(), name='favorite'),
     path('articles/favorites/me/',
          ListUserFavoriteArticlesView.as_view(), name='get_favorite'),
+    path('articles/<slug>/rate/',
+         RateArticleAPIView.as_view(), name='rating_articles'),
 ]