pydantic-jsonschema 0.0.4

JSON Schema to Pydantic model conversion library

Pydantic JSON Schema

Convert JSON Schema definitions into Pydantic models with runtime validation.

Installation

uv add pydantic-jsonschema

Requires Python 3.12+. See the installation guide for optional format validator extras.

Quick Start

from pydantic_jsonschema import Schema, to_model

schema = Schema.model_validate({
    "type": "object",
    "properties": {
        "name": {"type": "string"},
        "age": {"type": "integer", "minimum": 0},
    },
    "required": ["name"],
})

User = to_model(schema, model_name="User")

user = User(name="Alice", age=30)
print(user.model_dump())
#> {'name': 'Alice', 'age': 30}

Schema Model

The Schema class is a Pydantic model representing a JSON Schema object. Use it to parse, inspect, and serialize schemas with full type safety:

from pydantic_jsonschema import DataType, Schema

schema = Schema(
    type=DataType.OBJECT,
    properties={
        "name": Schema(type=DataType.STRING),
    },
    required=["name"],
)

print(schema.model_dump_json(indent=4))
"""
{
    "type": "object",
    "properties": {
        "name": {
            "type": "string"
        }
    },
    "required": [
        "name"
    ]
}
"""

Schema supports $ref and $defs for reusable definitions — properties referencing a $ref are parsed as Reference objects and resolved automatically during conversion.

See the Schema documentation for field reference and usage examples.

Documentation

https://danipulok.github.io/pydantic-jsonschema/

Roadmap

• Custom JSON Schema implementation (remove openapi-pydantic dependency)
• Remove fqdn and rfc3986 dependencies
• Remove email-validator dependency
• Logic fixes in schema conversion
• Add inline_snapshot for tests
• Configurable loading by type (inspired by adaptix)

Acknowledgments

• vgavro — initial library idea, guidance, and ongoing support
• bodlan — contributions to documentation and conversion logic

License

MIT License - see LICENSE for details.