marimo-pydantic-form

[!WARNING] This package is under active development. Features and APIs may change.

A Python package for building marimo forms from Pydantic models.

[!NOTE] Currently, UI elements must be manually assigned to each field. Automatic UI element generation is planned for future releases.

Features

• Automatically generate marimo forms from Pydantic models
• Support for nested Pydantic models
• Customizable UI elements for each field
• Type-safe form validation using Pydantic
• Easy parsing of form values back into Pydantic model instances

Installation

pip install marimo-pydantic-form

Or using uv:

uv add marimo-pydantic-form

Quick Start

import marimo as mo
from pydantic import BaseModel
from marimo_pydantic_form import PydanticFormBuilder

class Inner(BaseModel):
    a: int

class Model(BaseModel):
    x: float
    y: Inner

# Create a form builder with custom UI elements
builder = PydanticFormBuilder(
    model=Model,
    ui={
        "x": mo.ui.slider(0, 100, label="x"),
        "y.a": mo.ui.slider(0, 100, label="y.a")
    },
)

# Build the form
form = builder.build()

# Parse the form value into a Pydantic model instance
model_instance = builder.parse(form.value)

Usage

Basic Form

Create a form from a Pydantic model:

from marimo_pydantic_form import PydanticFormBuilder

builder = PydanticFormBuilder(model=YourModel)
form = builder.build()

Custom UI Elements

Assign custom marimo UI elements to specific fields using dot notation for nested fields:

builder = PydanticFormBuilder(
    model=Model,
    ui={
        "field_name": mo.ui.text(label="Custom Label"),
        "nested.field": mo.ui.slider(0, 100)
    }
)

Parsing Form Values

Convert form values back to Pydantic model instances:

model_instance = builder.parse(form.value)

License

See LICENSE file for details.