Shiny

New features

* Added a new `ui.MarkdownStream()` component for performantly streaming in chunks of markdown/html strings into the UI. This component is primarily useful for text-based generative AI where responses are received incrementally. (1782)

* The `ui.Chat()` component now supports input suggestion links. This feature is useful for providing users with clickable suggestions that can be used to quickly input text into the chat. This can be done in 2 different ways (see 1845 for more details):
* By adding a `.suggestion` CSS class to an HTML element (e.g., `<span class="suggestion">A suggestion</span>`)
* Add a `data-suggestion` attribute to an HTML element, and set the value to the input suggestion text (e.g., `<span data-suggestion="Suggestion value">Suggestion link</span>`)
* To auto-submit the suggestion when clicked by the user, include the `.submit` class or the `data-suggestion-submit="true"` attribute on the HTML element. Alternatively, use Cmd/Ctrl + click to auto-submit any suggestion or Alt/Opt + click to apply any suggestion to the chat input without submitting.

* The `ui.Chat()` component also gains the following:
* The `.on_user_submit()` decorator method now passes the user input to the decorated function. This makes it a bit easier to access the user input. See the new templates (mentioned below) for examples. (1801)
* The assistant icon is now configurable via `ui.chat_ui()` (or the `ui.Chat.ui()` method in Shiny Express) or for individual messages in the `.append_message()` and `.append_message_stream()` methods of `ui.Chat()`. (1853)
* A new `latest_message_stream` property was added for an easy way to reactively read the stream's status, result, and also cancel an in progress stream. (1846)
* The `.append_message_stream()` method now returns the `reactive.extended_task` instance that it launches. (1846)
* The `ui.Chat()` component's `.update_user_input()` method gains `submit` and `focus` options that allow you to submit the input on behalf of the user and to choose whether the input receives focus after the update. (1851)

* `shiny create` includes new and improved `ui.Chat()` template options. Most of these templates leverage the new [`{chatlas}` package](https://posit-dev.github.io/chatlas/), our opinionated approach to interfacing with various LLM. (#1806)

* Client data values (e.g., url info, output sizes/styles, etc.) can now be accessed in the server-side Python code via `session.clientdata`. For example, `session.clientdata.url_search()` reactively reads the URL search parameters. (1832)

* Available `input` ids can now be listed via `dir(input)`. This also works on the new `session.clientdata` object. (1832)

* `ui.input_text()`, `ui.input_text_area()`, `ui.input_numeric()` and `ui.input_password()` all gain an `update_on` option. `update_on="change"` is the default and previous behavior, where the input value updates immediately whenever the value changes. With `update_on="blur"`, the input value will update only when the text input loses focus or when the user presses Enter (or Cmd/Ctrl + Enter for `ui.input_text_area()`). (1874)

* Added a new `.add_sass_layer_file()` method to `ui.Theme` that supports reading a Sass file with layer boundary comments, e.g. `/*-- scss:defaults --*/`. This format [is supported by Quarto](https://quarto.org/docs/output-formats/html-themes-more.html#bootstrap-bootswatch-layering) and makes it easier to store Sass rules and declarations that need to be woven into Shiny's Sass Bootstrap files. (1790)

* Added a new `expect_max_height()` method to the Valuebox controllers to check the maximum height of a value box (1816)

* `shiny.pytest.create_app_fixture(app)` gained support for multiple app file paths when creating your test fixture. If multiple file paths are given, it will behave as a parameterized fixture value and execute the test for each app path. (1869)

Breaking changes

* The navbar-related style options of `ui.page_navbar()` and `ui.navset_bar()` have been consolidated into a single `navbar_options` argument that pairs with a new `ui.navbar_options()` helper. Using the direct `position`, `bg`, `inverse`, `collapsible`, and `underline` arguments will continue to work with a deprecation message.

Related to this change, `ui.navset_bar()` now defaults to using `underline=True` so that it uses the same set of default `ui.navbar_options()` as the page variant. In `ui.navbar_options()`, `inverse` is replaced by `theme`, which takes values `"light"` (dark text on a **light** background), `"dark"` (light text on a **dark** background), or `"auto"` (follow page settings).

* The Shiny Core component `shiny.ui.Chat()` no longer has a `.ui()` method. This method
was never intended to be used in Shiny Core (in that case, use `shiny.ui.chat_ui()`) to create the UI element. Note that the `shiny.express.ui.Chat()` class still has a `.ui()` method. (1840)

Bug fixes

* `ui.Chat()` now correctly handles new `ollama.chat()` return value introduced in `ollama` v0.4. (1787)

* Updated `expect_height()` for Valuebox controllers to check the height property instead of max-height. (1816)

Bug fixes

* Branded theming via `ui.Theme.from_brand()` now correctly applies monospace inline and block font family choices. (1762)

* Compatibility with `websockets>=14.0`, which has changed its public APIs. Shiny now requires websockets 13 or later. (1769)

Breaking changes

* `.expect_inverse()` for Navset controllers in `shiny.playwright.controllers` now requires a `bool` value. To keep behavior the same, use `.expect_inverse(False)`. (1668)

* `.expect_layout()` for Navset controllers in `shiny.playwright.controllers` is now renamed to `.expect_fluid()` and requires a `bool` value. To keep behavior the same, use `.expect_fluid(True)`. (1668)

* `.expect_icon()` for Accordion controllers in `shiny.playwright.controllers` now requires a `bool` value instead of a `str`. (1710)

New features

* New features for `render.data_frame`:

* Added [narwhals](https://posit-dev.github.io/py-narwhals) support for `render.data_frame`. This allows for any eager data frame supported by narwhals to be returned from a `render.data_frame` output method. All internal methods and helper methods now leverage the `narwhals` API to be data frame agnostic. (#1570)

* Added `.data_patched()` reactive calculation that applies all `.cell_patches()` to `.data()`. (1719)

* Added `.update_cell_value()` method to programmatically update the contents of a data frame cell. (1719)

* Added `.update_data()` method to update the rendered data without resetting any user sort or filter. Note, all user edits will be forgotten. (1719)

* Added [narwhals](https://posit-dev.github.io/py-narwhals) support for `render.table`. This allows for any eager data frame supported by narwhals to be returned from a `render.table` output method. (#1570)

* Shiny now supports theming via [brand.yml](https://posit-dev.github.io/brand-yml) with a single `_brand.yml` file. Call `ui.Theme.from_brand()` with `__file__` or the path to a `_brand.yml` file and pass the resulting theme to the `theme` argument of `express.ui.page_opts()` (Shiny Express) or `ui.page_*()` functions (Shiny Core) to apply the brand theme to the entire app. (#1743)

* `chat_ui()` and `Chat.ui()` gain a `messages` parameter for providing starting messages. (1736)

Other changes

* Incorporated `orjson` for faster data serialization in `render.data_frame` outputs. (1570)

* Added `PageNavbar` class to the list of `shiny.playwright.controllers` for testing `ui.page_navbar()`. (1668)

* Added `.expect_widths()` to `NavsetPillList` in `shiny.playwright.controllers` for testing `ui.navset_pill_list(widths=)`. (1668)

* Added `.expect_title()` for `Popover` in `shiny.playwright.controllers` (1683)

* Added `.expect_disabled()` for `InputActionButton` in `shiny.playwright.controllers` (1705)

* Small improvements to the default pulse busy indicator to better blend with any background. It's also now slightly smaller by default.(1707)

* Added `.expect_class()`, `.expect_gap()`, `.expect_bg_color()`, `.expect_desktop_state()`, `.expect_mobile_state()`, `.expect_mobile_max_height()`, `.expect_title()`, and `.expect_padding()` for `Sidebar` in `shiny.playwright.controllers` (1715)

* Modified `.expect_text()` for `Sidebar` in `shiny.playwright.controllers` to use `.loc_content` instead of `loc` for text. Also modified `.expect_width()` to check the `.loc_container`'s style instead of the `.loc` element. (1715)

* Modified `.expect_text()` and `.expect_width()` for `Sidebar` in `shiny.playwright.controllers` to use `loc_content` instead of `loc` for text. (1715)

* Added `.expect_class()` and `.expect_multiple()` for `Accordion` in `shiny.playwright.controllers` (1710)

Bug fixes

* A few fixes for `ui.Chat()`, including:
* Fixed a bug with `Chat()` sometimes silently dropping errors. (1672)
* Fixed a bug with `Chat()` sometimes not removing it's loading icon (on error or a `None` transform). (1679)
* `.messages(format="anthropic")` correctly removes non-user starting messages (once again). (1685)

* `shiny create` now uses the template `id` rather than the directory name as the default directory. (1666)

* `ui.Theme()` now works correctly on Windows when the theme requires Sass compilation. (Thanks, yuuuxt!) (1684)

* Fixed multiple input controllers (`InputSlider`, `InputDate`, `InputDateRange`, `InputCheckbox`, and `InputCheckboxGroup`) in `shiny.playwright.controller` to check the `width` property within the `style` attribute. (1691, 1696, 1702)

* Fixed multiple input controllers (`InputSwitch`, `InputRadioButtons`, `InputNumeric`, `InputText`, `InputTextArea`, `InputPassword`, `InputActionButton`, and `InputActionLink`) in `shiny.playwright.controller` to correctly validate the `width` style property in `.expect_width(). (1705)

* Fixed input controller `InputTextArea` in `shiny.playwright.controller` to correctly validate the `resize` style property in `.expect_resize()`. (1705)

* Fixed a bug in `ui.conditional_panel()` that would cause the panel to repeatedly show/hide itself when the provided condition did not evaluate to a boolean value. (1707)

* Fixed a bug with `ui.input_slider()` when used as a range slider that made it impossible to change the slider value when both handles were at the maximum value. (1707)

* Fixed bug in `render.data_frame` where `bool` or `object` columns were not being rendered. (1570)

* Fixed output controller `OutputDataFrame` in `shiny.playwright.controller` to correctly assert the number of rows in `.expect_nrow()` as the total number of virtual rows, not the number of currently displaying rows. (1719)

* Fixed issue where `render.download` did not respect the module namespacing. (Thanks, nsiicm0!) (1732)

* Added workaround in `Accordion` in `shiny.playwright.controller` where `.expect_open()` and `.expect_panels()` would hang while resolving a playwright locator. (Thanks, joesho112358!) (1165)

New features

* `ui.Chat()` gains a new `.update_user_input()` method, which adds the ability to update the input placeholder message. As a result, `.set_user_message()` is now deprecated (since the new method can also be used to update the message). (1594)

* `shiny create` now supports a succinct format for specifying the GitHub repository via the `--github` flag, e.g. `--github posit-dev/py-shiny-templates`. You can now also use `--github` and `--template` together, in which case `--github` should point to a repository containing a directory matching the name provided in `--template`. (1623)

* `shiny create` now identifies templates in external repositories using a `_template.json` metadata file. This file should contain at an `"id"` and optionally a `"title"` and `"description"`. When `shiny create` is called with the `--github` flag but without a `--template` flag, it will offer a menu listing all available templates in the repository. (1631)

Other changes

* A few changes for `ui.Chat()`, including:
* The `.messages()` method no longer trims messages by default (i.e., the default value of `token_limits` is now `None` instead of the overly generic and conservative value of `(4096, 1000)`). See the new generative AI in production templates (via `shiny create`) for examples of setting `token_limits` based on the model being used. (1657)
* User input that contains markdown now renders the expected HTML. (1607)
* Busy indication is now visible/apparent during the entire lifecycle of response generation. (1607)

Bug fixes

* A few fixes for `ui.Chat()`, including:
* A fix for use inside Shiny modules. (1582)
* `.messages(format="google")` now returns the correct role. (1622)
* `transform_assistant_response` can now return `None` and correctly handles change of content on the last chunk. (1641)

* An empty `ui.input_date()` value no longer crashes Shiny. (1528)

* Fixed bug where calling `.update_filter(None)` on a data frame renderer did not visually reset non-numeric column filters. (It did reset the column's filtering, just not the label). Now it resets filter's label. (1557)

* Require shinyswatch >= 0.7.0 and updated examples accordingly. (1558)

* `ui.input_text_area(autoresize=True)` now resizes properly even when it's not visible when initially rendered (e.g. in a closed accordion or a hidden tab). (1560)

* `ui.notification_show(duration=None)` now persists the notification until the app user closes it. (1577)

* Some copies of Windows 10 have registry entries mapping .js files to content type "text/plain", which was causing all sorts of problems for browsers. (1624)

* Added missing support for `express.ui.navset_card_pill(placement:)`. (1602)

* Added `.expect_sidebar()` and `.expect_title()` methods for `NavsetCardTab`, `NavsetCardPill`, `NavsetCardUnderline`, and `NavsetBar`. (1602)

* Added `.expect_placement()` method for `NavsetCardPill` and `NavsetCardUnderline`. (1602)

Deprecations

New features

* Added a new `shiny.ui.Chat` class for building conversational interfaces with fully customizable and performant response generation. (1453)

* Expose `shiny.playwright`, `shiny.run`, and `shiny.pytest` modules that allow users to testing their Shiny apps. (1448, 1456, 1481)
* `shiny.playwright` contains `controller` and `expect` submodules. `controller` will contain **many** classes to interact with (and verify!) your Shiny app using Playwright. `expect` contains expectation functions that enhance standard Playwright expectation methods.
* `shiny.run` contains the `run_shiny_app` command and the return type `ShinyAppProc`. `ShinyAppProc` can be used to type the Shiny app pytest fixtures.
* `shiny.pytest` contains pytest test fixtures. The `local_app` pytest fixture is automatically available and runs a sibling `app.py` file. Where as `create_app_fixture(PATH_TO_APP)` allows for a relative path to a Shiny app to be instantiated from a different folder.

* Added CLI command `shiny add test` to add a test file to an existing Shiny app. (1461)

* `render.data_frame`, `render.DataGrid`, and `render.DataTable` now support `polars` data frames (1474).

* `render.data_frame`, `render.DataGrid`, and `render.DataTable` are now type aware. This means that the data frame renderer object's `.data()` and `.data_view()` methods will return the same type of data given the the renderer. E.g. If a `DataGrid` wrapping a `polars` data frame is returned to the renderer function, `.data_view()` will return `polars` data. (1502)

* `render.data_frame`'s `render.DataGrid` and `render.DataTable` added support for cell styling with the new `styles=` parameter. This parameter can receive a style info object (or a list of style info objects), or a function that accepts a data frame and returns a list of style info objects. Each style info object can contain the `rows` and `cols` locations where the inline `style` and/or CSS `class` should be applied. (1475)

* `render.data_frame` has added a few new methods:
* `.data_view_rows()` is a reactive value representing the sorted and filtered row numbers. This value wraps `input.<ID>_data_view_rows()`(1374)
* `.sort()` is a reactive value representing the sorted column information (dictionaries containing `col: int` and `desc: bool`). This value wraps `input.<ID>_sort()`. (1374)
* `.filter()` is a reactive value representing the filtered column information (dictionaries containing `col: int` and `value` which is either a string or a length 2 array of at least one non-`None` number). This value wraps `input.<ID>_filter()`. (1374)
* `.update_sort(sort=)` allows app authors to programmatically update the sorting of the data frame. (1374)
* `.update_filter(filter=)` allows app authors to programmatically update the filtering of the data frame. (1374)

* `render.data_frame` now accepts both a non-`"none"` `selection_mode` value and `editable=True`. (1454, 1534)

* `render.data_frame`'s `<ID>.cell_selection()` no longer returns a `None` value and now always returns a dictionary containing both the `rows` and `cols` keys. This is done to achieve more consistent author code when working with cell selection. When the value's `type="none"`, both `rows` and `cols` are empty tuples. When `type="row"`, `cols` represents all column numbers of the data. In the future, when `type="col"`, `rows` will represent all row numbers of the data. These extra values are not available in `input.<ID>_cell_selection()` as they are independent of cells being selected and are removed to reduce information being sent to and from the browser. (1376)

* Relative imports, like `from . import utils`, now can be used in Shiny Express apps. (1464)

* `ui.Theme` allows you to create custom themes for your Shiny app by recompiling [Bootstrap](https://getbootstrap.com/) and Shiny's Sass files with your own customizations. Themes created with `ui.Theme` can be passed directly to the `theme` argument of `express.ui.page_opts()` (Shiny Express) or `ui.page_*()` functions (Shiny Core) to apply the theme to the entire app. This feature requires the [libsass package](https://sass.github.io/libsass-python/) which can be installed with `pip install libsass`. (#1358)

* `ui.card_body()` can be used to wrap the contents of elements in `ui.card()`, allowing you to change parameters like `fillable` or `padding` and `gap` for groups of elements in the card. (1506)

Other changes

* `ui.input_action_button()` and `ui.update_action_button()` gain a `disabled` argument. When the button is disabled, it appears grayed out and cannot be clicked. (1465)

* The main content area of `ui.page_sidebar()` and `ui.page_navbar()` with a page-level `sidebar` now have a minimum height and width to avoid squashed content in fillable layouts. The minimum height and width are controllable via `--bslib-page-main-min-{width,height}` CSS variables. (1436)

* Added a new option to place an always-open sidebar *above the main content* on mobile screens by providing `open={"mobile": "always-above"}` to `ui.sidebar()`. (1436)

Bug fixes

* Fixed 1440: When a Shiny Express app with a `www/` subdirectory was deployed to shinyapps.io or a Connect server, it would not start correctly. (1442)

* Fixed 1498: Update table related TypeScript dependencies to their latest versions. This fixed an issue where the Row Virtualizer would scroll to the end when hidden. This would cause the DOM to update numerous times, locking up the browser tab for multiple seconds. (1524, 1550)

* The return type for the data frame patch function now returns a list of `render.CellPatch` objects (which support `htmltools.TagNode` for the `value` attribute). These values will be set inside the data frame's `.data_view()` result. This also means that `.cell_patches()` will be a list of `render.CellPatch` objects. (1526)

* Made sure all `render.data_frame` cells that have been edited are now restored back to ready state to handle the off chance that the returned patches are at different locations the the original edit patches. (1529)

* `remove_all_fill(tag)` no longer modifies the original `tag` input and instead returns a modified copy of `tag`. (1538)

Deprecations

* The following deprecated functions have now been removed (1546):
* `shiny.ui.panel_sidebar()` was deprecated in v0.6.0; use `shiny.ui.sidebar()` instead.
* `shiny.ui.panel_main()` was deprecated in v0.6.0; instead pass items directly to `shiny.ui.layout_sidebar()`.
* `shiny.ui.navset_pill_card()` was deprecated in v0.6.0; use `shiny.ui.navset_card_pill()` instead.
* `shiny.ui.navset_tab_card()` was deprecated in v0.6.0; use `shiny.ui.navset_card_tab()` instead.
* `shiny.ui.nav()` was deprecated in v0.6.1; use `shiny.ui.nav_panel()` instead.

* `render.data_frame`, `render.DataGrid`, and `render.DataTable` have deprecated support for data frame types that are `pandas` compatible. Please call `.to_pandas()` on your data before it is returned to the renderer (1502). Currently, both `polars` and `pandas` data frames are supported (1474). If you'd like to add support for a new data frame type, please open an issue or a pull request.

* `render.data_frame`'s `.cell_selection()` will no longer return `None` when the selection mode is `"none"`. In addition, missing `rows` or `cols` information will be populated with appropiate values. This allows for consistent handling of the cell selection object. (1374)

* `render.data_frame`'s input value `input.<ID>_data_view_indices()` has been deprecated. Please use `<ID>.data_view_rows()` to retrieve the same information. (1377)

* `render.data_frame`'s input value `input.<ID>_column_sort()` has been deprecated. Please use `<ID>.sort()` to retrieve the same information. (1374)

* `render.data_frame`'s input value `input.<ID>_column_filter()` has been deprecated. Please use `<ID>.filter()` to retrieve the same information. (1374)

* Deprecated functions in `shiny.experimental` have been removed. By and large, these functions are now available in the main `shiny` namespace. (1540)

* We've deprecated several card-related `shiny.experimental.ui` functions that were moved to the main `shiny.ui` namespace in v0.6.0. Both `card()` and `card_body()` are no longer experimental and can be called via `shiny.ui.card()` and `shiny.ui.card_body()` directly. `shiny.experimental.ui.card_title()` is now deprecated, but can be replaced with `shiny.ui.tags.h5()` or `shiny.ui.card_header()`. (1543)

Bug fixes

* Fixed an issue with output spinners only showing for a split second. (1429)