graphene-django-optimizer

import graphene from django.db import models from django.conf import settings from graphene_django.types import DjangoObjectType from graphene_django_optimizer import DjangoOptimizerExtension # Minimal Django setup required for DjangoObjectType to function # In a real Django project, these settings would be in your settings.py if not settings.configured: settings.configure( INSTALLED_APPS=['graphene_django', 'graphene_django_optimizer', 'myapp'], DATABASES={'default': {'ENGINE': 'django.db.backends.sqlite3', 'NAME': ':memory:'}}, GRAPHENE={'EXTENSIONS': [DjangoOptimizerExtension]}, # Enable globally via settings # Needed for Django models to be discovered MIGRATION_MODULES={'myapp': None} ) import django django.setup() # Define a simple Django model class Author(models.Model): name = models.CharField(max_length=100) class Meta: app_label = 'myapp' # Critical for in-memory Django setup class Book(models.Model): title = models.CharField(max_length=200) author_obj = models.ForeignKey(Author, on_delete=models.CASCADE, related_name='books') class Meta: app_label = 'myapp' # Define Graphene types for the models class AuthorType(DjangoObjectType): class Meta: model = Author fields = ("id", "name", "books") class BookType(DjangoObjectType): class Meta: model = Book fields = ("id", "title", "author_obj") # Define a Graphene Query class Query(graphene.ObjectType): all_authors = graphene.List(AuthorType) all_books = graphene.List(BookType) def resolve_all_authors(root, info): # The DjangoOptimizerExtension will automatically apply select_related/prefetch_related # for related fields requested in the GraphQL query (e.g., 'books' on AuthorType) return Author.objects.all() def resolve_all_books(root, info): return Book.objects.all() # Create the Graphene Schema # The extension is enabled via settings.GRAPHENE['EXTENSIONS'] schema = graphene.Schema(query=Query) # --- Example Usage (for demonstration, not typically part of quickstart.code) --- # Create some dummy data author1 = Author.objects.create(name="Douglas Adams") author2 = Author.objects.create(name="Jane Austen") Book.objects.create(title="The Hitchhiker's Guide to the Galaxy", author_obj=author1) Book.objects.create(title="Pride and Prejudice", author_obj=author2) Book.objects.create(title="The Restaurant at the End of the Universe", author_obj=author1) # Define a GraphQL query that would typically cause N+1 without optimization query = """ query { allBooks { id title author_obj { name } } } """ # Execute the query result = schema.execute(query) # Check for errors and data (in a real scenario, you'd inspect logs for N+1) assert not result.errors assert len(result.data['allBooks']) == 3 assert result.data['allBooks'][0]['author_obj']['name'] == 'Douglas Adams' print("Optimization enabled successfully! Check your database query logs if available.")