ninja-schema 0.12.6

Django Schema - Builds Pydantic Schemas from Django Models with default field type validations

Ninja Schema

Ninja Schema converts your Django ORM models to Pydantic schemas with more Pydantic features supported.

Inspired by: django-ninja and djantic

Requirements

Python >= 3.6, django >= 2.1, pydantic >= 1.6

Key features:

• Custom Field Support: Ninja Schema converts django model to native pydantic types which gives you quick field validation out of the box. eg Enums, email, IPAddress, URLs, JSON, etc
• Field Validator: Fields can be validated with model_validator just like pydantic validator or root_validator.

Installation

pip install ninja-schema

Configuration Properties

• model: Django Model
• include: Fields to include, default: '__all__'
• exclude: Fields to exclude, default: set()
• optional: Fields to mark optional, default: set() optional = '__all__' will make all schema fields optional
• depth: defines depth to nested generated schema, default: 0

model_validator(*args, **kwargs)

model_validator is a substitute for pydantic validator used for pre and post fields validation. There functionalities are the same. More info pydantic validators

from django.contrib.auth import get_user_model
from ninja_schema import ModelSchema, model_validator

UserModel = get_user_model()


class CreateUserSchema(ModelSchema):
    class Config:
        model = UserModel
        include = ['username', 'email', 'password']

    @model_validator('username')
    def validate_unique_username(cls, value_data: str) -> str:
        if UserModel.objects.filter(username__icontains=value_data).exists():
            raise ValueError('Username exists')
        return value_data

from_orm(cls, obj: Any)

You can generate a schema instance from your django model instance

from typings import Optional
from django.contrib.auth import get_user_model
from ninja_schema import ModelSchema, model_validator

UserModel = get_user_model()
new_user = UserModel.objects.create_user(
    username='eadwin', email='[e-mail]', 
    password='password', first_name='Emeka', last_name='Okoro'
)


class UserSchema(ModelSchema):
    class Config:
        model = UserModel
        include = ['id','first_name', 'last_name', 'username', 'email']

schema = UserSchema.from_orm(new_user)
print(schema.json(indent=2)
{
    "id": 1,
    "first_name": "Emeka",
    "last_name": "Okoro",
    "email": "[e-mail]",
    "username": "eadwin",
}

apply(self, model_instance, **kwargs)

You can now transfer your data from your ModelSchema to your model with ninja schema apply function. The apply function uses .dict pydantic function to copy the schema data to dict. The .dict pydantic function gives more filtering options which can be pass as kwargs to the .apply function.

For more info, visit Pydantic model export

from typings import Optional
from django.contrib.auth import get_user_model
from ninja_schema import ModelSchema, model_validator

UserModel = get_user_model()
new_user = UserModel.objects.create_user(username='eadwin', email='[e-mail]', password='password')


class UpdateUserSchema(ModelSchema):
    class Config:
        model = UserModel
        include = ['first_name', 'last_name', 'username']
        optional = ['username']  # `username` is now optional

schema = UpdateUserSchema(first_name='Emeka', last_name='Okoro')
schema.apply(new_user, exclude_none=True)

assert new_user.first_name == 'Emeka' # True
assert new_user.username == 'eadwin' # True

Generated Schema Sample

from django.contrib.auth import get_user_model
from ninja_schema import ModelSchema, model_validator

UserModel = get_user_model()


class UserSchema(ModelSchema):
    class Config:
        model = UserModel
        include = '__all__'
        depth = 2

        
print(UserSchema.schema())

{
    "title": "UserSchema",
    "type": "object",
    "properties": {
        "id": {"title": "Id", "extra": {}, "type": "integer"},
        "password": {"title": "Password", "maxLength": 128, "type": "string"},
        "last_login": {"title": "Last Login","type": "string", "format": "date-time"},
        "is_superuser": {"title": "Superuser Status",
            "description": "Designates that this user has all permissions without explicitly assigning them.",
            "default": false,
            "type": "boolean"
        },
        "username": {
            "title": "Username",
            "description": "Required. 150 characters or fewer. Letters, digits and @/./+/-/_ only.",
            "maxLength": 150,
            "type": "string"
        },
        "first_name": {
            "title": "First Name",
            "maxLength": 150,
            "type": "string"
        },
        "last_name": {
            "title": "Last Name",
            "maxLength": 150,
            "type": "string"
        },
        "email": {
            "title": "Email Address",
            "type": "string",
            "format": "email"
        },
        "is_staff": {
            "title": "Staff Status",
            "description": "Designates whether the user can log into this admin site.",
            "default": false,
            "type": "boolean"
        },
        "is_active": {
            "title": "Active",
            "description": "Designates whether this user should be treated as active. Unselect this instead of deleting accounts.",
            "default": true,
            "type": "boolean"
        },
        "date_joined": {
            "title": "Date Joined",
            "type": "string",
            "format": "date-time"
        },
        "groups": {
            "title": "Groups",
            "description": "The groups this user belongs to. A user will get all permissions granted to each of their groups.",
            "type": "array",
            "items": {
                "$ref": "#/definitions/Group"
            }
        },
        "user_permissions": {
            "title": "User Permissions",
            "description": "Specific permissions for this user.",
            "type": "array",
            "items": {
                "$ref": "#/definitions/Permission"
            }
        }
    },
    "required": [
        "password",
        "username",
        "groups",
        "user_permissions"
    ],
    "definitions": {
        "Permission": {
            "title": "Permission",
            "type": "object",
            "properties": {
                "id": {
                    "title": "Id",
                    "extra": {},
                    "type": "integer"
                },
                "name": {
                    "title": "Name",
                    "maxLength": 255,
                    "type": "string"
                },
                "content_type_id": {
                    "title": "Content Type",
                    "type": "integer"
                },
                "codename": {
                    "title": "Codename",
                    "maxLength": 100,
                    "type": "string"
                }
            },
            "required": [
                "name",
                "content_type_id",
                "codename"
            ]
        },
        "Group": {
            "title": "Group",
            "type": "object",
            "properties": {
                "id": {
                    "title": "Id",
                    "extra": {},
                    "type": "integer"
                },
                "name": {
                    "title": "Name",
                    "maxLength": 150,
                    "type": "string"
                },
                "permissions": {
                    "title": "Permissions",
                    "type": "array",
                    "items": {
                        "$ref": "#/definitions/Permission"
                    }
                }
            },
            "required": [
                "name",
                "permissions"
            ]
        }
    }
}