Overriding Pydantic Config

There are many customizations available for a Django Ninja Schema, via the schema's Pydantic Config class.

Info

Under the hood Django Ninja uses Pydantic Models with all their power and benefits. The alias Schema was chosen to avoid confusion in code when using Django models, as Pydantic's model class is called Model by default, and conflicts with Django's Model class.

Automatic Camel Case Aliases

One useful Config attribute is alias_generator. We can use it to automatically generate aliases for field names with a given function. This is mostly commonly used to create an API that uses camelCase for its property names. Using Pydantic's example in Django Ninja can look something like:

from ninja import Schema
from pydantic.alias_generators import to_camel


class CamelModelSchema(Schema):
    str_field_name: str
    float_field_name: float

    class Config(Schema.Config):
        alias_generator = to_camel

Note

When overriding the schema's Config, it is necessary to inherit from the base Schema.Config class.

To alias ModelSchema's field names, you'll also need to set populate_by_name on the Schema config and enable by_alias in all endpoints using the model.

class UserSchema(ModelSchema):
    class Config(Schema.Config):
        alias_generator = to_camel
        populate_by_name = True  # !!!!!! <--------

    class Meta:
        model = User
        model_fields = ["id", "email", "created_date"]


@api.get("/users", response=list[UserSchema], by_alias=True) # !!!!!! <-------- by_alias
def get_users(request):
    return User.objects.all()

results:

[
  {
    "id": 1,
    "email": "tim@apple.com",
    "createdDate": "2011-08-24"
  },
  {
    "id": 2,
    "email": "sarah@smith.com",
    "createdDate": "2012-03-06"
  },
  ...
]

Custom Config from Django Model

When using create_schema, the resulting schema can be used to build another class with a custom config like:

from django.contrib.auth.models import User
from ninja.orm import create_schema


BaseUserSchema = create_schema(User)


class UserSchema(BaseUserSchema):

    class Config(BaseUserSchema.Config):
        ...