dash-fn-form

Introspection-based UI engine for Plotly Dash — transform type-hinted Python functions into reactive Dash forms.

Installation

pip install dash-fn-form

Most users should install dash-interact instead, which includes this package and adds a convenience page API.

Usage

from dash import Dash, html
from dash_fn_form import build_fn_panel

def sine_wave(amplitude: float = 1.0, frequency: float = 2.0):
    import numpy as np, plotly.graph_objects as go
    x = np.linspace(0, 6 * np.pi, 600)
    return go.Figure(go.Scatter(x=x, y=amplitude * np.sin(frequency * x)))

app = Dash(__name__)
app.layout = html.Div([build_fn_panel(sine_wave)])
app.run(debug=True)

build_fn_panel inspects the function signature and builds a form with matching controls. The return value is rendered automatically.

Type mapping

Python type	Control
float	Number input (or slider with (min, max, step))
int	Number input (integer step)
bool	Checkbox
Literal[A, B, C]	Dropdown
str	Text input
date / datetime	Date picker
list[T] / tuple[T, ...]	Comma-separated input
T | None	Same as T, submits None when empty

Field customization

from dash_fn_form import Field

form = FnForm("my_form", my_fn, title=Field(label="Title", col_span=2))

License

MIT