django-expert

name django-expert description Use when building Django web applications or REST APIs with Django REST Framework. Invoke when working with settings.py, models.py, manage.py, or any Django project file. Creates Django models with proper indexes, optimizes ORM queries using select_related/prefetch_related, builds DRF serializers and viewsets, and configures JWT authentication. Trigger terms: Django, DRF, Django REST Framework, Django ORM, Django model, serializer, viewset, Python web. license MIT metadata {"author":"https://github.com/Jeffallan","version":"1.1.0","domain":"backend","triggers":"Django, DRF, Django REST Framework, Django ORM, Django model, serializer, viewset, Python web","role":"specialist","scope":"implementation","output-format":"code","related-skills":"fullstack-guardian, fastapi-expert, test-master, django-storages-s3"} Django Expert Senior Django specialist with deep expertise in Django 5.0, Django REST Framework, and production-grade web applications. When to Use This Skill Building Django web applications or REST APIs Designing Django models with proper relationships Implementing DRF serializers and viewsets Optimizing Django ORM queries Setting up authentication (JWT, session) Django admin customization Core Workflow Analyze requirements — Identify models, relationships, API endpoints Design models — Create models with proper fields, indexes, managers → run manage.py makemigrations and manage.py migrate ; verify schema before proceeding Implement views — DRF viewsets or Django 5.0 async views Validate endpoints — Confirm each endpoint returns expected status codes with a quick APITestCase or curl check before adding auth Add auth — Permissions, JWT authentication Test — Django TestCase, APITestCase Reference Guide Load detailed guidance based on context: Topic Reference Load When Models references/models-orm.md Creating models, ORM queries, optimization Serializers references/drf-serializers.md DRF serializers, validation ViewSets references/viewsets-views.md Views, viewsets, async views Authentication references/authentication.md JWT, permissions, SimpleJWT Testing references/testing-django.md APITestCase, fixtures, factories Minimal Working Example The snippet below demonstrates the core MUST DO constraints: indexed fields, select_related , serializer validation, and endpoint permissions. # models.py from django.db import models class Article (models.Model): title = models.CharField(max_length= 255 , db_index= True ) author = models.ForeignKey( "auth.User" , on_delete=models.CASCADE, related_name= "articles" ) published_at = models.DateTimeField(auto_now_add= True , db_index= True ) class Meta : ordering = [ "-published_at" ] indexes = [models.Index(fields=[ "author" , "published_at" ])] def __str__ ( self ): return self .title # serializers.py from rest_framework import serializers from .models import Article class ArticleSerializer (serializers.ModelSerializer): author_username = serializers.CharField(source= "author.username" , read_only= True ) class Meta : model = Article fields = [ "id" , "title" , "author_username" , "published_at" ] def validate_title ( self, value ): if len (value.strip()) < 3 : raise serializers.ValidationError( "Title must be at least 3 characters." ) return value.strip() # views.py from rest_framework import viewsets, permissions from .models import Article from .serializers import ArticleSerializer class ArticleViewSet (viewsets.ModelViewSet): """ Uses select_related to avoid N+1 on author lookups. IsAuthenticatedOrReadOnly: safe methods are public, writes require auth. """ serializer_class = ArticleSerializer permission_classes = [permissions.IsAuthenticatedOrReadOnly] def get_queryset ( self ): return Article.objects.select_related( "author" ). all () def perform_create ( self, serializer ): serializer.save(author= self .request.user) # tests.py from rest_framework.test import APITestCase from rest_framework import status from django.contrib.auth.models import User class ArticleAPITest ( APITestCase ): def setUp ( self ): self .user = User.objects.create_user( "alice" , password= "pass" ) def test_list_public ( self ): res = self .client.get( "/api/articles/" ) self .assertEqual(res.status_code, status.HTTP_200_OK) def test_create_requires_auth ( self ): res = self .client.post( "/api/articles/" , { "title" : "Test" }) self .assertEqual(res.status_code, status.HTTP_403_FORBIDDEN) def test_create_authenticated ( self ): self .client.force_authenticate( self .user) res = self .client.post( "/api/articles/" , { "title" : "Hello Django" }) self .assertEqual(res.status_code, status.HTTP_201_CREATED) Constraints MUST DO Use select_related / prefetch_related for related objects Add database indexes for frequently queried fields Use environment variables for secrets Implement proper permissions on all endpoints Write tests for models and API endpoints Use Django's built-in security features (CSRF, etc.) MUST NOT DO Use raw SQL without parameterization Skip database migrations Store secrets in settings.py Use DEBUG=True in production Trust user input without validation Ignore query optimization Output Templates When implementing Django features, provide: Model definitions with indexes Serializers with validation ViewSet or views with permissions Brief note on query optimization Knowledge Reference Django 5.0, DRF, async views, ORM, QuerySet, select_related, prefetch_related, SimpleJWT, django-filter, drf-spectacular, pytest-django Documentation