ViewSet Pattern

from rest_framework import viewsets, status from rest_framework.response import Response from rest_framework.decorators import action

class UserViewSet(viewsets.ModelViewSet): queryset = User.objects.all() serializer_class = UserSerializer filterset_class = UserFilter permission_classes = [IsAuthenticated]

def get_serializer_class(self):
    if self.action == "create":
        return UserCreateSerializer
    if self.action in ["update", "partial_update"]:
        return UserUpdateSerializer
    return UserSerializer

@action(detail=True, methods=["post"])
def activate(self, request, pk=None):
    user = self.get_object()
    user.is_active = True
    user.save()
    return Response({"status": "activated"})

Serializer Patterns

from rest_framework import serializers

Read Serializer

class UserSerializer(serializers.ModelSerializer): full_name = serializers.SerializerMethodField()

class Meta:
    model = User
    fields = ["id", "email", "full_name", "created_at"]
    read_only_fields = ["id", "created_at"]

def get_full_name(self, obj):
    return f"{obj.first_name} {obj.last_name}"

Create Serializer

class UserCreateSerializer(serializers.ModelSerializer): password = serializers.CharField(write_only=True)

class Meta:
    model = User
    fields = ["email", "password", "first_name", "last_name"]

def create(self, validated_data):
    password = validated_data.pop("password")
    user = User(**validated_data)
    user.set_password(password)
    user.save()
    return user

Update Serializer

class UserUpdateSerializer(serializers.ModelSerializer): class Meta: model = User fields = ["first_name", "last_name"]

Filters

from django_filters import rest_framework as filters

class UserFilter(filters.FilterSet): email = filters.CharFilter(lookup_expr="icontains") is_active = filters.BooleanFilter() created_after = filters.DateTimeFilter( field_name="created_at", lookup_expr="gte" ) created_before = filters.DateTimeFilter( field_name="created_at", lookup_expr="lte" )

class Meta:
    model = User
    fields = ["email", "is_active"]

Permissions

from rest_framework.permissions import BasePermission

class IsOwner(BasePermission): def has_object_permission(self, request, view, obj): return obj.owner == request.user

class IsAdminOrReadOnly(BasePermission): def has_permission(self, request, view): if request.method in ["GET", "HEAD", "OPTIONS"]: return True return request.user.is_staff

Pagination

from rest_framework.pagination import PageNumberPagination

class StandardPagination(PageNumberPagination): page_size = 20 page_size_query_param = "page_size" max_page_size = 100

settings.py

REST_FRAMEWORK = { "DEFAULT_PAGINATION_CLASS": "api.pagination.StandardPagination", }

URL Routing

from rest_framework.routers import DefaultRouter

router = DefaultRouter() router.register(r"users", UserViewSet, basename="user") router.register(r"posts", PostViewSet, basename="post")

urlpatterns = [ path("api/v1/", include(router.urls)), ]

Testing

import pytest from rest_framework import status from rest_framework.test import APIClient

@pytest.fixture def api_client(): return APIClient()

@pytest.fixture def authenticated_client(api_client, user): api_client.force_authenticate(user=user) return api_client

@pytest.mark.django_db class TestUserViewSet: def test_list_users(self, authenticated_client): response = authenticated_client.get("/api/v1/users/") assert response.status_code == status.HTTP_200_OK

def test_create_user(self, authenticated_client):
    data = {"email": "new@test.com", "password": "pass123"}
    response = authenticated_client.post("/api/v1/users/", data)
    assert response.status_code == status.HTTP_201_CREATED

Commands

python manage.py runserver python manage.py makemigrations python manage.py migrate python manage.py createsuperuser python manage.py shell