User Feed Including Following:

tweet_feed_view:

• create tweet_feed_view in /tweets/api/views.py ```python

  …

@api_view([‘GET’]) # http method the client === GET @permission_classes([IsAuthenticated]) def tweet_feed_view(request, args, *kwargs): user = request.user profiles = user.following.all() # user.following.all() -> All user profiles this user follow followed_users_id = [] if profiles.exists(): followed_users_id = [x.user.id for x in profiles] followed_users_id.append(user.id) qs = Tweet.objects.filter(useridin=followed_users_id).order_by(“-timestamp”) serializer = TweetSerializer(qs, many=True) return Response(serializer.data, status=200)

…

- import tweet_feed_view in /tweets/api/urls.py
```python
from django.contrib import admin
from django.urls import path
from .views import (
    tweet_detail_view, 
    tweet_list_view,
    tweet_create_view,
    tweet_delete_view,
    tweet_action_view,
    tweet_feed_view, # new
)
urlpatterns = [
    path('', tweet_list_view),
    path('feed/', tweet_list_view), # new
    path('action/', tweet_action_view),
    path('create/', tweet_create_view),
    path('<int:tweet_id>/', tweet_detail_view),
    path('<int:tweet_id>/delete/', tweet_delete_view),
]

to test, runserver and access http://localhost/api/tweets/feed/

there is no actually following relationship found, and we need a more efficient way to call profiles in the database.

More Efficient Backend Lookups and Custom Model Managers:

• we apply Q with 2 new functions in /tweets/models.py
• Q stands for “query” ```python

  …

from django.db.models import Q

class TweetQuerySet(models.QuerySet): def by_username(self, username): return self.filter(userusernameiexact=username)

def feed(self, user):
    profiles_exist = user.following.exists()
    followed_users_id = []
    if profiles_exist:
        followed_users_id = user.following.values_list(
            "user__id", flat=True)  # [x.user.id for x in profiles]
    return self.filter(
        Q(user__id__in=followed_users_id) |
        Q(user=user)
    ).distinct().order_by("-timestamp") 
    # use query to pass user id and user
    # distint for the same element only appears once
    # order by reversed time

class TweetManager(models.Manager): def get_queryset(self, args, *kwargs): return TweetQuerySet(self.model, using=self._db)

def feed(self, user):
    return self.get_queryset().feed(user)

…

- and use those new models and model methods in /tweets/api/views.py
```python
@api_view(['GET'])
@permission_classes([IsAuthenticated])
def tweet_feed_view(request, *args, **kwargs):
    user = request.user
    # profiles = user.following.all() # user.following.all() -> All user profiles this user follow
    # if profiles.exists():
    #     followed_users_id = [x.user.id for x in profiles]
    # followed_users_id.append(user.id)
    # qs = Tweet.objects.filter(user__id__in=followed_users_id).order_by("-timestamp")
    qs = Tweet.objects.feed(user)
    serializer = TweetSerializer(qs, many=True)
    return Response(serializer.data, status=200)
@api_view(['GET'])
def tweet_list_view(request, *args, **kwargs):
    qs = Tweet.objects.all()
    username = request.GET.get('username') 
    if username != None:
        # qs = qs.filter(user__username__iexact=username)
        qs = qs.by_username(username)  # moved this part to a method in TweetQuerySet()
    serializer = TweetSerializer(qs, many=True)
    # return Response(serializer.data)
    return Response( serializer.data,status=200)