feat(follow users) follow and unfollow users

- update profile model to include following functionality
- update profile serializer to add a following field to the profile serialized data
- write tests for the following functionality
- add endpoints for the follow functionality to the url.py file
- write functions to handle the follow functionlity

[finishes #165890222]

authors/apps/profiles/migrations/0002_follow.py

@@ -0,0 +1,24 @@
+# Generated by Django 2.1 on 2019-05-10 06:54
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ('profiles', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Follow',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('followed', models.ForeignKey(default=False, on_delete=django.db.models.deletion.CASCADE, related_name='followed', to=settings.AUTH_USER_MODEL)),
+                ('follower', models.ForeignKey(default=False, on_delete=django.db.models.deletion.CASCADE, related_name='follower', to=settings.AUTH_USER_MODEL)),
+            ],
+        ),
+    ]

authors/apps/profiles/models.py

@@ -28,3 +28,12 @@ def create_user_profile(sender, instance, created, **kwargs):
 def save_profile(sender, instance, **kwargs):
     instance.userprofile.save()
 
+
+class Follow(models.Model):
+    follower = models.ForeignKey(User,
+                                 related_name="follower",
+                                 on_delete=models.CASCADE,
+                                 default=False)
+    followed = models.ForeignKey(User, related_name="followed",
+                                 on_delete=models.CASCADE,
+                                 default=False)

authors/apps/profiles/serializers.py

@@ -1,5 +1,5 @@
 from rest_framework import serializers
-from authors.apps.profiles.models import UserProfile
+from authors.apps.profiles.models import UserProfile, Follow
 from .models import User
 import re
 
@@ -12,16 +12,26 @@ class Meta:
 
 class UpdateProfileSerializer(serializers.ModelSerializer):
     username = serializers.ReadOnlyField(source='user.username')
+    following = serializers.SerializerMethodField()
     class Meta:
         model = UserProfile
         fields = (
             'firstname',
             'lastname',
             'username',
             'image',
-            'bio'
+            'bio',
+            'following'
         )
 
+    def get_following(self, instance):
+        current_user = self.context['request'].user
+        following = False
+        if Follow.objects.filter(followed=instance.user,
+                                 follower=current_user).exists():
+            following = True
+        return following
+
     def validate_username(self, username):
         username1 =  User.objects.filter(username=username)
         if username1.exists():

authors/apps/profiles/tests/test_follow.py

@@ -0,0 +1,55 @@
+from django.urls import reverse
+from rest_framework import status
+from .base import BaseTestCase
+
+
+class FollowTestCase(BaseTestCase):
+    """Testcases for following a user."""
+
+    def test_follow_user_post(self):
+        """Test start following a user."""
+        url = reverse('follow', kwargs={'username': 'test2'})
+        response = self.client.post(url, HTTP_AUTHORIZATION=self.auth_header)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+
+    def test_post_follow_already_followed_user(self):
+        """Test start following a user you already follow."""
+        url = reverse('follow', kwargs={'username': 'test2'})
+        self.client.post(url, HTTP_AUTHORIZATION=self.auth_header)
+        response = self.client.post(url, HTTP_AUTHORIZATION=self.auth_header)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+
+    def test_follow_missing_user_post(self):
+        """Test trying to start following a missing user."""
+        url = reverse('follow', kwargs={'username': 'joel'})
+        response = self.client.post(url, HTTP_AUTHORIZATION=self.auth_header)
+        self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
+
+    def test_delete_follow(self):
+        """Test unfollowing a user"""
+        url = reverse('follow', kwargs={'username': 'test2'})
+        self.client.post(url, HTTP_AUTHORIZATION=self.auth_header)
+        response = self.client.delete(url, HTTP_AUTHORIZATION=self.auth_header)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+
+    def test_delete_follow_of_not_followed_user(self):
+        """Test unfollowing a user you are not following"""
+        url = reverse('follow', kwargs={'username': 'test2'})
+        response = self.client.delete(url, HTTP_AUTHORIZATION=self.auth_header)
+        self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
+
+    def test_list_followers_of_user(self):
+        """Test list followers of a user"""
+        url_follow = reverse('follow', kwargs={'username': 'test2'})
+        self.client.post(url_follow, HTTP_AUTHORIZATION=self.auth_header)
+        url_followers = reverse('getfollowers', kwargs={'username': 'test2'})
+        response = self.client.get(url_followers, HTTP_AUTHORIZATION=self.auth_header)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+
+    def test_list_user_is_following(self):
+        """Test list users the user is following"""
+        url_follow = reverse('follow', kwargs={'username': 'test2'})
+        self.client.post(url_follow, HTTP_AUTHORIZATION=self.auth_header)
+        url_following = reverse('getfollowing', kwargs={'username': 'test1'})
+        response = self.client.get(url_following, HTTP_AUTHORIZATION=self.auth_header)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)

authors/apps/profiles/urls.py

@@ -1,7 +1,15 @@
 from django.urls import path
-from .views import UserProfiles, Updateprofile
+from .views import UserProfiles, Updateprofile, \
+     FollowView, Followers, Following
 
 urlpatterns = [
     path('users/profiles/', UserProfiles.as_view(), name="get_profile"),
-    path('users/profile/<str:username>/', Updateprofile.as_view(), name="update_profile")
+    path('users/profile/<str:username>/', Updateprofile.as_view(),
+         name="update_profile"),
+    path('profiles/<str:username>/follow/', FollowView.as_view(),
+         name="follow"),
+    path('profiles/<str:username>/followers/', Followers.as_view(),
+         name="getfollowers"),
+    path('profiles/<str:username>/following/', Following.as_view(),
+         name="getfollowing")
 ]

authors/apps/profiles/views.py

@@ -3,9 +3,11 @@
 from rest_framework.response import Response
 from django.shortcuts import get_object_or_404
 from rest_framework import status
+from rest_framework.views import APIView
 from rest_framework.permissions import IsAuthenticated, AllowAny
+from rest_framework.exceptions import NotFound
 from .renderers import ProfileJSONRenderer
-from .models import UserProfile
+from .models import UserProfile, Follow
 from .models import User
 
 
@@ -41,13 +43,88 @@ def put(self, request, *args, **kwargs):
         profile = self.get_object()
         if str(profile) == str(request.user.username):
             serializer = self.serializer_class(profile,
-                                           data=request.data['profile'])
+                                               data=request.data['profile'],
+                                               context={'request': request})
             serializer.is_valid(raise_exception=True)
             serializer.save(data=request.data)
-            return Response(UpdateProfileSerializer(profile).data)
+            return Response(serializer.data)
         return Response(
             data={'message':
                     'You have no permissions to edit others profile.'},
             status=status.HTTP_403_FORBIDDEN
         )
 
+def get_user_object(username):
+    # get user object
+    try:
+        return User.objects.get(username=username)
+    except User.DoesNotExist:
+        raise NotFound(detail='User not found.')
+
+
+class FollowView(APIView):
+    #Function to handle follow user functionality
+    permission_classes = (IsAuthenticated,)
+
+    def get_follow_object(self, follower, followed):
+        # Method to get a follow object
+        try:
+            return Follow.objects.get(follower=follower, followed=followed)
+        except Follow.DoesNotExist:
+            return None
+
+    def post(self, request, username):
+        # post to follow a user
+        user = get_user_object(username)
+        if user == request.user:
+            return Response({'error': 'Sorry, you can not follow your self.'},
+                            status=status.HTTP_400_BAD_REQUEST)
+        if not self.get_follow_object(request.user, user):
+            Follow(followed=user, follower=request.user).save()
+        message = f"You are following {user.username}."
+        return Response({'message': message}, status=status.HTTP_200_OK,)
+
+    def delete(self, request, username):
+        # unfollow a user
+        user = get_user_object(username)
+        follow_Obj = self.get_follow_object(request.user, user)
+        if not follow_Obj:
+            return Response({'error': f'You are not following {user.username}.'},
+                            status=status.HTTP_400_BAD_REQUEST)
+        follow_Obj.delete()
+        message = f"You have successfully unfollowed {user.username}."
+        return Response({'message': message}, status=status.HTTP_200_OK,)
+
+
+class Followers(APIView):
+    """ Return users that follow the provided username"""
+    permission_classes = (IsAuthenticated,)
+
+    def get(self, request, username):
+        # get the user's followers
+        user = get_user_object(username)
+        followers = Follow.objects.filter(followed=user)
+        profiles = "No followers for "+username
+        for value in followers:
+            profiles = []
+            profile = UserProfile.objects.get(user=value.follower)
+            profile = FetchUserProfileSerializer(profile)
+            profiles.append(profile.data)
+        return Response(profiles, status=status.HTTP_200_OK,)
+
+
+class Following(APIView):
+    """ Return users that the provided username follows"""
+    permission_classes = (IsAuthenticated,)
+
+    def get(self, request, username):
+        # get users this user follows
+        user = get_user_object(username)
+        followings = Follow.objects.filter(follower=user)
+        profiles = username+" is not following any users"
+        for value in followings:
+            profiles = []
+            profile = UserProfile.objects.get(user=value.followed)
+            profile = FetchUserProfileSerializer(profile)
+            profiles.append(profile.data)
+        return Response(profiles, status=status.HTTP_200_OK,)