Update as_widget() to use the new altair.JupyterChart (#113)

Author: cpsievert

CHANGELOG.md

@@ -5,6 +5,10 @@ All notable changes to shinywidgets will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [UNRELEASED]
+
+* `as_widget()` uses the new `altair.JupyterChart()` to coerce `altair.Chart()` into a `ipywidgets.widgets.Widget` instance. (#120)
+
 ## [0.2.2] - 2023-10-31
 
 * `@render_widget` now builds on `shiny`'s `render.transformer` infrastructure, and as a result, it works more seamlessly in `shiny.express` mode. (#110)

README.md

@@ -18,18 +18,19 @@ See the [using ipywidgets section](https://shiny.rstudio.com/py/docs/ipywidgets.
 
 ### What ipywidgets are supported?
 
-In theory, shinywidgets supports any instance that inherits from `{ipywidgets}`' `Widget` class.
+In theory, shinywidgets supports any instance that inherits from `{ipywidgets}`' `Widget` class. That is, if `isinstance(obj, ipywidgets.widgets.Widget)` returns `True` for some object `obj`, then `{shinywidgets}` should be able to render it.
 
-That said, `{shinywidgets}` can also "directly" render objects that don't inherit from `Widget`, but have a known way of coercing into a `Widget` instance. This list currently includes:
+`{shinywidgets}` can also render objects that don't inherit from `Widget`, but have a known way of coercing into a `Widget` instance. This list currently includes:
 
-* Altair charts (via the [vega](https://pypi.org/project/vega/) package).
-* Bokeh widgets (via the [jupyter_bokeh](https://github.com/bokeh/jupyter_bokeh) package).
-* Plotly's `Figure` class (via `FigureWidget`).
+* Altair charts (i.e., `altair.Chart()` instances).
+* Plotly figures (i.e., `plotly.go.Figure()`)
 * Pydeck's `Deck` class (via it's `.show()` method).
+* Bokeh widgets (via the [jupyter_bokeh](https://github.com/bokeh/jupyter_bokeh) package).
+  * Bokeh widgets are a bit of a special case, as they require some extra setup to work in Shiny. See the [Bokeh widgets aren't displaying, what gives?](#bokeh-widgets-arent-displaying-what-gives) section below for more details.
 
-[See here](https://github.com/rstudio/py-shinywidgets/blob/main/shinywidgets/_as_widget.py) for more details on how these objects are coerced into `Widget` instances, and if you know of other packages that should be added to this list, please [let us know](https://github.com/rstudio/py-shinywidgets/issues/new)
+[See here](https://github.com/rstudio/py-shinywidgets/blob/main/shinywidgets/_as_widget.py) for more details on how these objects are coerced into `Widget` instances, and if you know of other packages that should be added to this list, please [let us know](https://github.com/rstudio/py-shinywidgets/issues/new).
 
-### Bokeh widgets aren't displaying, what gives?
+### Bokeh setup
 
 Similar to how you have to run `bokeh.io.output_notebook()` to run `{bokeh}` in notebook, you also have to explicitly bring the JS/CSS dependencies to the Shiny app, which can be done this way:
 
@@ -94,26 +95,6 @@ that widget requires initialization code in a notebook environment. In this case
 `{shinywidgets}` probably won't work without providing the equivalent setup information to
 Shiny. Some known cases of this are:
 
-#### bokeh
-
-To use `{bokeh}` in notebook, you have to run `bokeh.io.output_notebook()`. The
-equivalent thing in Shiny is to include the following in the UI definition:
-
-```py
-from shiny import ui
-from shinywidgets import bokeh_dependencies
-
-app_ui = ui.page_fluid(
-    bokeh_dependencies(),
-    # ...
-)
-```
-
-
-#### Other widgets?
-
-Know of another widget that requires initialization code? [Please let us know about
-it](https://github.com/rstudio/py-shinywidgets/issues/new)!
 
 ## Development
 

shinywidgets/__init__.py

@@ -2,9 +2,15 @@
 
 __author__ = """Carson Sievert"""
 __email__ = "[email protected]"
-__version__ = "0.2.2"
+__version__ = "0.2.2.9000"
 
 from ._dependencies import bokeh_dependency
-from ._shinywidgets import output_widget, reactive_read, register_widget, render_widget, as_widget
+from ._shinywidgets import (
+    as_widget,
+    output_widget,
+    reactive_read,
+    register_widget,
+    render_widget,
+)
 
 __all__ = ("output_widget", "register_widget", "render_widget", "reactive_read", "bokeh_dependency", "as_widget")

shinywidgets/_as_widget.py

@@ -31,19 +31,13 @@ def as_widget(x: object) -> Widget:
 
 def as_widget_altair(x: object) -> Optional[Widget]:
     try:
-        from vega.widget import VegaWidget
+        from altair import JupyterChart
     except ImportError:
-        raise ImportError("Install the vega package to use altair with shinywidgets.")
-
-    if not hasattr(x, "to_dict"):
-        raise TypeError(
-            f"Don't know how to coerce {x} (an altair object) into an ipywidget without a .to_dict() method."
+        raise RuntimeError(
+            "Failed to import altair.JupyterChart (do you need to pip install -U altair?)"
         )
 
-    try:
-        return VegaWidget(x.to_dict())  # type: ignore
-    except Exception as e:
-        raise RuntimeError(f"Failed to coerce {x} into a VegaWidget: {e}")
+    return JupyterChart(x)  # type: ignore
 
 
 def as_widget_bokeh(x: object) -> Optional[Widget]: