Make it easy to use dataclass like models using familiar apis

panel/ipywidget.py

@@ -0,0 +1,49 @@
+"""Functionality to enable easily interacting with ipywidgets via familiar APIs like pn.bind,
+@pn.depends and pn.rx"""
+
+from typing import TYPE_CHECKING, Iterable
+
+import param
+
+from .viewable import Viewer
+
+if TYPE_CHECKING:
+    try:
+        from traitlets import HasTraits
+    except ModuleNotFoundError:
+
+        class HasTraits:  # type: ignore
+            """Mock class"""
+
+else:
+
+    class HasTraits:  # type: ignore
+        """Mock class"""
+
+
+def to_viewer(widget: HasTraits, parameters: Iterable | None = None, **kwargs) -> Viewer:
+    """Returns a Viewer object with parameters synced to the ipywidget widget parameters
+
+    Args:
+        widget (HasTraits): The ipywidget to create the Viewer from.
+        parameters (Iterable | None): The parameters to add to the Viewer and to sync.
+            If no parameters are specified all parameters on the widget will be added
+            and synced.
+        kwargs: Any kwargs provided will be forwarded to the IPyWidget pane used to display the
+            widget.
+    """
+    raise NotImplementedError()
+
+
+def to_rx(
+    widget: HasTraits, parameters: Iterable | None = None
+) -> tuple[param.rx, ...]:
+    """Returns a tuple of `rx` parameters. Each one synced to a parameter of the ipywidget widget.
+
+    Args:
+        widget (HasTraits): The ipywidget to create the `rx` parameters from.
+        parameters (Iterable): The parameters to create `rx` parameters from and to sync.
+            If no parameters are specified all parameters on the widget will be added
+            and synced.
+    """
+    raise NotImplementedError()

panel/tests/test_ipywidget.py

@@ -0,0 +1,135 @@
+"""We test that we can work with Ipywidgets and AnyWidgets via Parameters or Reactive values
+instead of Traitlets observer pattern.
+
+The purpose is to enable Panel users to easily use Ipywidgets using familiar APIs.
+"""
+
+import param
+
+from traitlets import (
+    Float, HasTraits, Int, Unicode,
+)
+
+import panel as pn
+
+from panel.ipywidget import to_rx, to_viewer
+
+
+class ExampleTraitlets(HasTraits):
+    name = Unicode("Default Name").tag(description="A string trait")
+    age = Int(0).tag(description="An integer trait")
+    height = Float(0.0).tag(description="A float trait")
+
+
+def test_to_viewer():
+    widget = ExampleTraitlets(name="A", age=1, height=1.1)
+
+    viewer = to_viewer(widget)
+
+    assert isinstance(viewer, pn.viewable.Viewer)
+    assert {"name", "age", "height"} == set(viewer.param.params)
+
+    assert viewer.name == widget.name
+    assert viewer.age == widget.age
+    assert viewer.height == widget.height
+
+    # widget synced to widget
+    widget.name = "B"
+    widget.age = 2
+    widget.height = 2.2
+    assert viewer.name == widget.name
+    assert viewer.age == widget.age
+    assert viewer.height == widget.height
+
+    # widget synced to viewer
+    viewer.name = "C"
+    viewer.age = 3
+    viewer.height = 3.3
+    assert viewer.name == widget.name
+    assert viewer.age == widget.age
+    assert viewer.height == widget.height
+
+    component = viewer.__panel__()
+    assert isinstance(component, pn.pane.IPyWidget)
+    assert component.object == widget
+
+
+def test_to_viewer_parameter_list():
+    widget = ExampleTraitlets(name="A", age=1, height=1.1)
+
+    viewer = to_viewer(widget, parameters=["name", "age"])
+
+    assert isinstance(viewer, pn.viewable.Viewer)
+    assert {"name", "age"} == set(viewer.param.params)
+
+    assert viewer.name == widget.name
+    assert viewer.age == widget.age
+
+    # widget synced to widget
+    widget.name = "B"
+    widget.age = 2
+    assert viewer.name == widget.name
+    assert viewer.age == widget.age
+
+    # widget synced to viewer
+    viewer.name = "C"
+    viewer.age = 3
+    assert viewer.name == widget.name
+    assert viewer.age == widget.age
+
+def test_to_viewer_kwargs():
+    widget = ExampleTraitlets(name="A", age=1, height=1.1)
+
+    viewer = to_viewer(widget, parameters=["name", "age"], sizing_mode="stretch_width")
+    assert viewer.__panel__().sizing_mode=="stretch_width"
+
+def test_to_rx():
+    widget = ExampleTraitlets(name="A", age=1, height=1.1)
+
+    name, age, height = to_rx(widget)
+    assert isinstance(name, param.rx)
+    assert isinstance(age, param.rx)
+    assert isinstance(height, param.rx)
+
+    assert name.rx.value == widget.name
+    assert age.rx.value == widget.age
+    assert height.rx.value == widget.height
+
+    # widget synced to reactive
+    widget.name = "B"
+    widget.age = 2
+    widget.height = 2.2
+    assert name.rx.value == widget.name
+    assert age.rx.value == widget.age
+    assert height.rx.value == widget.height
+
+    # reactive synced to viewer
+    name.rx.value = "C"
+    age.rx.value = 3
+    height.rx.value = 3.3
+    assert name.rx.value == widget.name
+    assert age.rx.value == widget.age
+    assert height.rx.value == widget.height
+
+
+def test_to_rx_parameter_list():
+    widget = ExampleTraitlets(name="A", age=1, height=1.1)
+
+    name, age = to_rx(widget, parameters=["name", "age"])
+    assert isinstance(name, param.rx)
+    assert isinstance(age, param.rx)
+
+    assert name.rx.value == widget.name
+    assert age.rx.value == widget.age
+
+    # widget synced to reactive
+    widget.name = "B"
+    widget.age = 2
+    assert name.rx.value == widget.name
+    assert age.rx.value == widget.age
+
+    # reactive synced to viewer
+    name.rx.value = "C"
+    age.rx.value = 3
+    assert name.rx.value == widget.name
+    assert age.rx.value == widget.age