panel

This release is a small bug fix release preceding the upcoming major release of Panel 1.0. Many thanks to the contributors to this release which include @MarcSkovMadsen, @maximlt, @Hoxbro and @philippjfr.

Bugs

• Fix Tabulator client-side string filters by not parsing them as regex (4423)
• Fix the RGGPlot pane (#4380)
• Fix panel examples command by ensuring examples are correctly packaged (#4484)
• Fix event generation by considering NaNs as equal when comparing Numpy arrays (#4481)
• Use cache from previous sessions when using to_disk (#4481)
• Fix relative imports when running inside Jupyter Kernel (#4489)
• Do not re-create Vega.selections object unless selections changed (#4497)

Enhancements

• Add support for altair and vega-lite v5 (#4488)

Misc

• Use latest react-grid from CDN (#4461)

This release introduces a large number of bug fixes and minor enhancements. Due to the upcoming release of Panel 1.0 we have also made the unconventional decision to issue new deprecation in a micro release. Specifically the IDOM pane and Viewable.app and Viewable.pprint methods have been scheduled for deprecation. Many thanks to the contributors to this release which include @wendrul, @droumis and the core team @MarcSkovMadsen, @maximlt, @Hoxbro and @philippjfr.

Bugs

Tabulator

• Ensure streamed rows on Tabulator can be edited (#4292)
• Ensure changes on Tabulator formatter and editor models are reflected in frontend (#4296)
• Ensure cancelling edit does not clear cell on Tabulator (#4343)
• Ensure inserting empty data on numeric column in Tabulator does not error (#4343)

Notebook

• Fix issues rendering components as ipywidgets for some versions of ipykernel (#4289)
• Add warning if custom resources could not be loaded in notebook (#4329)
• Ensure notifications are enabled even if hv.extension has been loaded (#4330)
• Ensure global notification object can be used inside notebook callbacks (#4331)

Type definitions

• Fix return type of Widget.from_param (#4335)
• Ensure type annotation allows str and PathLike objects on panel.serve (#4336)
• Fix type annotations on panel.io.convert.convert_app(s) (#4342)

Misc

• Ensure markdown links render correctly in template sidebar (#4222)
• Improve .applies for ECharts and DeckGL (#4224)
• Fix specifying custom --index with relative path (#4288)
• Skip on_load callbacks in liveness check (#4302)
• Ensure re-rendered FileDownload still fetches live data (#4328)
• Fix handling of panel.cache on undecorated Parameterized method (#4332)
• Ensure user provided hash_funcs are applied in panel.cache (#4334)
• Fix plotly eventdata undefined val (#4355)
• Ensure panel convert respects panel.config options (#4359)
• Propagate options from HoloViews and Bokeh plots to enclosing Pane (#4360)
• Propagate options from dynamic components such as ParamMethod and Interactive to enclosing layout (#4360)

Minor enhancements

• Allow to set the log level of the Admin logger (#3495)
• Make refresh_token available in Auth (#4227)
• Simplify determining whether script is executed as application with pn.state.served property (#4252)
• Add loading_indicator to global config (#4259)
• IPython display compatibility in pyodide builds (#4270)
• Split PanelJupyterExecutor into separate module (#4276)
• Allow dynamic loading of javascript modules in ReactiveHTML (#4319)
• Add Plotly.link_figure parameter (#4333)
• Ensure CrossSelector filters apply on each keystroke (#4339)
• Improve startup, error handling and shutdown of Jupyter kernels in jupyter_server_extension (#4364)

Compatibility and Version Updates

• Upgrade plotly.js to 2.10.1 (#4320)
• Upgrade to pyodide 0.22.1 in panel convert (#4334)
• Upgrade to pyscript 2022.12.01 in panel convert (#4334)
• Fix compatibility of Perspective pane with Numpy 1.24 (#4362)

Deprecations

• Add deprecation warning to IDOM pane (#4293)
• Add deprecation warning for Viewable.app and Viewable.pprint methods (#4293, #4347)

Documentation

• Add CONTRIBUTING.md (#4262)
• Add Gallery VideoStream example (#4047)
• Add description of literal options to the docs for ReactiveHTML (#3803)

This release primarily focuses on bug fixes. In particular it resolves various issues with support for rendering ipywidgets (particularly in ipywidgets>=8.0) and also fixes a number of issues with the Jupyter Server previews. Many thanks for @govinda18, @joelostblom, @banesullivan, @xeldnahcram, @geronimogoemon, @minasouliman, @peterfpeterson, @jlstevens and the core maintainers @maximlt, @Hoxbro, @MarcSkovMadsen and @philippjfr for their contributions to this release.

Enhancements

• Add support for Tqdm.process_map (#4093)
• Support non-vtkPolyData types in vtk synchronizer (#4124)
• Allow invoking convert functions from pyodide (#4135)
• Support step format in date sliders (#4152)
• Add a Reacton component to simplify rendering (#4190)

Bugs

• Ensure Jupyter server extension serves resources, extensions and paths correctly (#4083, #4133, #4202)
• Ensure IPyWidget comm does not break when new widget is rendered (#4091)
• Improving detection of comms in VSCode and Google Colab (#4115)
• Ensure .js mimetype is served correctly on Windows (#4118)
• Ensure unhiding Tabulator columns renders cells correctly (#4119)
• Ensure embedded Slider widgets initialize with correct default (#4121)
• Handle missing event loop in thread gracefully (#4123)
• Ensure Matplotlib pane handles explicit width/height settings correctly (#4128)
• Allow Viewer to render servable but non-viewable objects (#4131)
• Fix regression in tracking sessions in admin interface (#4132)
• Ensure Tabs headers do not scroll unncessarily (#4146)
• Ensure Location model reports as idle (#4159)
• Fix auth error template rendering (#4162)
• Fix issues with value on EditableSlider when it is outside fixed_start / fixed_end range (#4169)
• Ensure ipywidgets events are handled the same way as regular events (#4171)
• Don't raise TypeError for class which contains __panel__ (#4174)
• Do not dispatch events if bokeh Document is set to hold events (#4178)
• Execute onload callbacks immediately in pyodide app (#4191)
• Improve IPyWidget kernel handling in server contexts (#4195)
• Fix rendering of IPyWidget with child views in the notebook (#4197)

Docs

• Add JupyterLite build and instructions (#4122)
• Document deployment to Hugging Face Spaces (#4143)

This release primarily addresses regressions introduced in 0.14.0 and various long standing bugs. Many thanks to external contributors @liu-kan and @KedoKudo and the maintainers @Hoxbro, @maximlt and @philippjfr for contributing a number of fixes.

### Minor enhancements

- Improve support for requests in pyodide (#3973) - Add option to clear value of DatetimePicker (#3990) - Add support for hashing dates in pn.cache (#4004) - Silence EMPTY_LAYOUT warnings (#4056)

### Compatibility

- Fix Jupyterlite and latest PyScript compatibility (#4040)

### Bugs

#### Webassembly conversion

- Correctly handle resource mode in when converting to WebAssembly (#3967)

### Jupyter and Server

- Correctly handle future exceptions on threads (#3977) - Fix panel serve index template (#3980) - Do not error if curdoc has been destroyed (#3994) - Ensure extensions loaded in jupyter kernel are served by StaticHandler (#4000) - Various fixes for OAuth handling with pn.serve (#4006) - Fix bug in on_load callback exception handling (#4007) - Ensure periodic callbacks are only started on main thread (#4011) - Ensure jupyter server extension handles explicit root_dir (#4029) - Ensure futures are correctly awaited when executed on thread (#4031)

#### Components

- Ensure Tabulator handles filtering on edited values correctly if show_index=False (#3988, #4016) - Ensure Tabulator declares numeric sorter for numeric dtypes (#3999) - Fix regression initializing DiscreteSlider with non-integer value (#4009) - Ensure that template.config.raw_css is correctly applied (#4018) - Fix handling MenuButton clicks when split=True (#4021) - Ensure styling on Tabulator with empty DataFrame does not error (#4028) - Allow changing level on Debugger widget (#4057

This release focuses on three main themes:

• Support for running Panel apps entirely in the browser using WebAssembly (via Pyodide and PyScript)
• Improvements in the app-user experience by making it easier to build responsive and performant applications
• Improvements in the developer experience through static typing and docstrings.

Many, many thanks to everyone who filed issues or contributed to this release. In particular we would like to thank @janimo, @xavArtley, @thuydotm, @jmosbacher, @dmarx, @2WoLpH, @ipopa144, @sdc50 for contributions and @philippjfr, @Hoxbro, @maximlt, and @MarcSkovMadsen for ongoing maintenance and development.

Features

• Add support for converting Panel apps to pyscript/pyodide (#3817, #3830, #3851, #3856, #3857, #3858, #3860, #3861, #3863, #3864, #3868, #3878)
• Manage our own CDN to improve performance and reliability for delivering JS payloads (#3867, #3870)
• Add ability to defer_load of components (#3882)
• Add pn.widget helper function (#1826, #3589)
• Add config.exception_handler to easily capture, log and notify users about errors (#3893)
• Implement pn.cache function for memoization support (#2411)
• Rewrite server extension to run Panel applications in kernels so that previews run in the same environment as the deployed app (#3763)
• Add ability to define authorization callback (#3777)
• Support memray profiler (#3509)
• Add liveness endpoint (#3832)
• Add ability to configure exception handler (#3896)

Enhancements

• Ensure OAuth redirects to requested app and retains query arguments (#3555)
• Add extension entry point (#3738)
• Update Admin Logs page to use Tabulator (#3694)
• Ensure location.unsync unsets query params (#3806)
• Allow None value on numeric sliders and LiteralInput (#3174)
• Allow serving admin panel with pn.serve (#3798)
• Improve ReactiveHTML loop support and validation (#3813)
• Support declaring Perspective.plugin_config pane (#3814)
• Do not flicker busy indicator during --autoreload check (#3804)
• Improve robustness of state.curdoc in threaded and async contexts (#3776, #3810, #3834)
• Support datetime bounds for DatetimePicker and DatetimeRangePicker (#3788)
• Allow setting the Oauth provider using environment variables (#3698)
• Implement Player.value_throttled (#3756)
• Ensure that URL query parameters are preserved during OAuth (#3656)
• Improve Markdown code syntax highlighting (#3758)
• Ensure components do not re-render if background or loading parameters change (#3599)
• Add ability to define admin dashboard plugins (#3668)
• Do not calculate embed state for disabled widgets (#3757)
• Add hard bounds to editable sliders (#3739)
• Add bundling of shared resources (#3894)
• Add Tabulator as default param.DataFrame widget (#3912)

Documentation

• Overhaul documentation (#3568)
• Improve Fast Template docstrings (#3570)
• Reorganize docs and convert static notebooks to Markdown (#3875, #3833)
• Add DevelopingCustomModels to the webpage (#3710)
• Improve typing (#3561, #3562, #3592, #3604, #3714, #3729)

Compatibility & Version updates

• Support ipywidgets>=8.0 (#3782)
• Bump jsoneditor package (#3838)
• Upgrade to Tabulator 5.3.2 (#3784)
• Improve Django compatibility (#3843, #3835)
• Remove all usage of deprecated Pane

Bugs

Server

• Ensure closed websocket does not cause errors
• Handle session and websocket close cleanly (#3769)
• Fix prefix handling for admin page (#3809)
• Support admin dashboard in multi-process deployments (#3812)
• Improve document cleanup when not invoked using server_destroy (#3842)
• Ensure pn.state.execute dispatches immediately if possible (#3859)
• Ensure autoload.js resources are appropriately prefixed (#3873)

Notebook

• Fix support for copying cells and creating new views in JupyterLab (#3652)
• Ensure output renders in VSCode notebook with latest ipywidgets (#3765)
• Resolve issues with Jupyter slowdown due to event_loop patching on Windows (#3770)
  • Ensure old comm managers do not raise errors in notebook (#3853)
  • Simplify rendering of ipywidget (#3937)

Tabulator

• Do not re-render Tabulator on css_classes or background change (#3598)
• Ensure expand icon updates on Tabulator.expanded change (#3703)
• Update page Parameter when pagination is 'local' (#3704)
• Do not apply sorters on Tabulator cell edits (#3744)
• Ensure Tabulator.controls renders (#3768)
• Ensure correctness of event row and selection indices in Tabulator (#3771, #3841)
• Fix issues with frontend and backend sorters being out of sync in Tabulator (#3825, #3839)
• Fix default values of a list header filter in Tabulator (#3826)
• Fix the edit event with a python filter in Tabulator (#3829)
• Disable client-side date filtering on Tabulator (#3849)
• Support editing of pandas masked array dtypes in Tabulator (#3850)
• Fix issues editing a cell when client-side filtering applied (#3852)
• Do not recompute data when local pagination is enabled (#3854)
• Don't skip filtering when the column name is undefined (#3862)

Misc

• Fix FileInput.save (#3579)
• Fix issues with Matplotlib.high_dpi option (#3591, #3594)
• Ensure layout recomputes on HTML/Markdown re-rerender (#3616)
• Allow overriding all widget parameters on Param pane (#3754)
• Ensure DatePicker start/end are transformed when jslinked (#3759)
• Ensure notifications can be enabled without a template (#3820)
• Ensure ReactiveHTML inline callbacks on loop variables return correct node (#3840)
• Ensure that Perspective does not take precedence on empty dict (#3936)
• Improve sizing_mode behavior when width/height are specified (#3955)
• Do not load notyf resources unless notifications are enabled (#3958)