Merge pull request #34 from andela/ft-tag-articles-164046260

#164046260 Users can add tags to articles

authors/apps/articles/models.py

@@ -12,6 +12,7 @@
 from .utils import generate_unique_slug
 from django.db.models import Avg
 from cloudinary import CloudinaryImage
+from django.utils.text import slugify
 
 
 class Article(models.Model):
@@ -25,6 +26,7 @@ class Article(models.Model):
     description = models.CharField(max_length=255, null=True)
     published = models.BooleanField(default=False)
     activated = models.BooleanField(default=True)
+    tags = models.ManyToManyField('Tag', related_name='articles', blank=True)
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
     author = models.ForeignKey(
@@ -168,3 +170,72 @@ def get_image(self):
 
     def __str__(self):
         return "This is rating no: " + str(self.id)
+
+
+class Tag(models.Model):
+    tag = models.CharField(max_length=100, db_index=True, unique=True)
+    slug = models.SlugField(max_length=240, db_index=True, unique=True)
+
+    def save(self, *args, **kwargs):
+        if not self.slug:
+            self.slug = slugify(self.tag)
+        super().save(*args, **kwargs)
+
+    def __str__(self):
+        return self.slug
+
+    objects = models.Manager()
+
+    def _create_tag(self, tag_name):
+        '''
+        This method checks if the tag exists and returns the tag object
+        else it creates a new tag object and returns it.
+        '''
+        found = Tag.objects.filter(slug=slugify(tag_name))
+        if len(found) < 1:
+            Tag.objects.create(tag=tag_name)
+        return Tag.objects.filter(slug=slugify(tag_name)).first()
+
+    def _remove_tags_without_articles(self, tag_name):
+        '''This method takes a tag name and checks if the tag has
+        associated articles and if not it deletes the tag from the
+        database in order to save on database space.
+        '''
+        found = Tag.objects.filter(slug=slugify(tag_name))
+        if found and len(found) > 0:
+            the_tag = Tag.objects.filter(slug=slugify(tag_name)).first()
+            its_articles = the_tag.articles.all()
+            if len(its_articles) < 1:
+                the_tag.delete()
+                return True
+        return False
+
+    def _update_article_tags(self, instance, new_tag_list):
+        '''This method is used to update the tags of an
+        article and do general tag mainenance.'''
+        old_tags = instance.tags.all()
+        old_tag_slugs = [tag.slug for tag in old_tags]
+        new_tag_slugs = [slugify(tag) for tag in new_tag_list]
+        # Check for items in the old list that are not in the new
+        # list and remove them.
+        tags_to_remove = list(set(old_tag_slugs) - set(new_tag_slugs))
+        remove_tag_objects = [
+            tag for tag in old_tags if (
+                tag.slug in tags_to_remove
+            )
+        ]
+        for item in remove_tag_objects:
+            # Remove tag from article
+            instance.tags.remove(item)
+            # Check if tag has any other article else delete the tag.
+            self._remove_tags_without_articles(item.tag)
+        new_slugs = list(set(new_tag_slugs) - set(old_tag_slugs))
+        tags_to_add = [tag for tag in new_tag_list if(
+            slugify(tag) in new_slugs
+        )]
+        for item in tags_to_add:
+            # Create tag if tag does not exist
+            the_tag = self._create_tag(item)
+            # Add the tag to the article instance.
+            instance.tags.add(the_tag)
+        return True

authors/apps/articles/renderers.py

@@ -6,13 +6,21 @@
 from rest_framework.utils.serializer_helpers import ReturnDict
 
 from ..authentication.models import User
+from ..articles.models import Tag
 
 
 class ArticleJSONRenderer(JSONRenderer):
     '''JSONRenderClass for formatting Article model data into JSON.'''
     charset = 'utf-8'
 
     def _single_article_formatting(self, data):
+        tags = data.pop("tags")
+        tagList = []
+        for item in tags:
+            this_tag = Tag.objects.filter(pk=item).first()
+            tagList.append(this_tag.tag)
+        data["tagList"] = tagList
+
         author = User.objects.all().filter(
             pk=data['author']).first()
         the_data = {

authors/apps/articles/serializers.py

@@ -3,7 +3,7 @@
 from authors.apps.profiles.serializers import ProfileSerializer
 
 from .models import (Article, Favorite, Like, Snapshot,
-                     ThreadedComment, Rating)
+                     ThreadedComment, Rating, Tag)
 
 
 class TheArticleSerializer(serializers.ModelSerializer):
@@ -15,15 +15,25 @@ class Meta:
         model = Article
         fields = [
             'id', 'title', 'body', 'draft', 'slug',
-            'reading_time', 'average_rating',
+            'reading_time', 'average_rating', 'tags',
             'editing', 'description', 'published', 'activated',
             "created_at", "updated_at", 'author'
         ]
         read_only_fields = ['slug']
 
     def create(self, validated_data):
         '''Create a new Article instance, given the accepted data.'''
-        article = Article.objects.create(**validated_data)
+        article_data = validated_data
+        tags_data = None
+        if 'tags' in validated_data.keys():
+            tags_data = article_data.pop("tags")
+        article = Article.objects.create(**article_data)
+
+        if tags_data:
+            for item in tags_data:
+                my_tag = Tag()
+                found = my_tag._create_tag(item)
+                article.tags.add(found)
         return article
 
     def update(self, instance, validated_data):
@@ -46,6 +56,11 @@ def update(self, instance, validated_data):
         instance.activated = validated_data.get(
             'activated', instance.activated
         )
+        if 'tags' in validated_data.keys() and len(validated_data['tags']) > 0:
+            this_tag = Tag()
+            new_tags = validated_data['tags']
+            this_tag._update_article_tags(instance, new_tags)
+
         instance.save()
         return instance
 

authors/apps/articles/tests/test_article_views.py

@@ -42,7 +42,9 @@ def setUp(self):
                 "title": "How to train your dragon",
                 "description": "Ever wonder how?",
                 "body": "You have to believe",
-                "draft": "Giving exellence high priority"
+                "draft": "Giving exellence high priority",
+                "tagList": ["dragons", "training"],
+
             }
         }
 
@@ -207,8 +209,9 @@ def test_update_article_successfully(self):
             "article": {
                 "title": "I am a champion",
                 "description": "In God we trust.",
-                "body": "One step infron of the other",
+                "body": "One step infront of the other",
                 "draft": "Giving exellence high priority",
+                "tagList": ["andela", "The OG"],
                 "activated": True
             }
         }

authors/apps/articles/tests/test_models_vol1.py

@@ -0,0 +1,64 @@
+from django.test import TestCase
+
+from authors.apps.articles.models import Tag, Article
+from authors.apps.authentication.models import User
+
+class ArticleModelTestCase(TestCase):
+
+    def setUp(self):
+        self.user_one = User.objects.create(
+            email = "jake@jake.jake",
+            password =  "jakejake",
+            username = "Jake"
+        )
+        self.article_one = Article.objects.create(
+            title = "I am the OG",
+            body = "This is an article by the OG",
+            author = self.user_one
+        )
+
+    def test_article_creation(self):
+
+        self.assertEqual(
+            self.article_one.__str__(),
+            "I am the OG"
+        )
+
+
+class  TagModelTestCase(TestCase):
+
+    def setUp(self):
+        self.user_one = User.objects.create(
+            email = "jake@jake.jake",
+            password =  "jakejake",
+            username = "Jake"
+        )
+        self.article_one = Article.objects.create(
+            title = "I am the OG",
+            body = "This is an article by the OG",
+            author = self.user_one
+        )
+
+    def test_tag_creation(self):
+        my_tag = Tag.objects.create(tag = "Etomovich")
+        my_tag.save()
+        self.assertEqual(
+            my_tag.slug,
+            "etomovich"
+        )
+
+    def test_delete_tags_without_articles(self):
+        my_tag = Tag(tag = "Etomovich")
+        my_tag.save()
+        remove_tag = my_tag._remove_tags_without_articles("Etomovich")
+        self.assertTrue(remove_tag)
+
+    def test_fail_to_delete_tags_with_articles(self):
+        a_tag = Tag.objects.create(tag = "Andela")
+        self.article_one.tags.add(a_tag)
+        remove_tag = a_tag._remove_tags_without_articles("Andela")
+        self.assertFalse(remove_tag)
+        remove_tag = a_tag._remove_tags_without_articles("Etomovich")
+        self.assertFalse(remove_tag)
+
+

authors/apps/articles/views.py

@@ -8,7 +8,7 @@
                           ArticleRatingSerializer)
 from .renderers import ArticleJSONRenderer, CommentJSONRenderer
 from .permissions import CanCreateComment, CanEditComment
-from .models import Article, Like, ThreadedComment, Favorite, Rating
+from .models import Article, Like, ThreadedComment, Favorite, Rating, Tag
 from authors.apps.core.views import BaseManageView
 from rest_framework.views import APIView, status
 from rest_framework.response import Response
@@ -30,6 +30,16 @@ def post(self, request, *args, **kwargs):
 
     def create(self, request, *args, **kwargs):
         payload = request.data.get('article', {})
+        the_tags = payload.get("tagList", None)
+        tags_pk = []
+        if the_tags:
+            the_tags = payload.pop("tagList")
+            tag_object = Tag()
+            for item in the_tags:
+                my_tag = tag_object._create_tag(item)
+                tags_pk.append(my_tag.pk)
+            payload["tags"] = tags_pk
+
         # Decode token
         this_user = request.user
         payload['author'] = this_user.pk
@@ -54,9 +64,9 @@ def list(self, request, *args, **kwargs):
         # Decode token
         reply_not_found = {}
         paginator = self.pagination_class()
-        page = paginator.paginate_queryset(self.queryset, request)
         published_articles = Article.objects.filter(
             published=True, activated=True)
+        page = paginator.paginate_queryset(published_articles, request)
 
         if (len(published_articles) < 1):
             reply_not_found["detail"] = "No articles have been found."
@@ -107,7 +117,6 @@ class UpdateAnArticleView(mixins.UpdateModelMixin,
 
     def _edit_article(self, request, the_data):
         if self.get_object().author == request.user:
-
             if self.get_object().activated is False:
                 invalid_entry = {
                     "detail": "This article does not exist."
@@ -118,6 +127,16 @@ def _edit_article(self, request, the_data):
                 )
 
             article_obj = self.get_object()
+            this_tags = the_data.get("tagList", None)
+            tags_pk = []
+            if this_tags:
+                this_tags = the_data.pop("tagList")
+                tag_object = Tag()
+                for item in this_tags:
+                    the_tag = tag_object._create_tag(item)
+                    tags_pk.append(the_tag.pk)
+                the_data["tags"] = tags_pk
+
             serialized = self.serializer_class(
                 article_obj, data=the_data, partial=True
             )