express.ui.MarkdownStream

express.ui.MarkdownStream(id, *, on_error='auto')

Examples

#| standalone: true
#| components: [editor, viewer]
#| layout: vertical
#| viewerHeight: 400

## file: app.py
import asyncio

import requests

from shiny import reactive
from shiny.express import session, ui

ui.page_opts(full_width=True)

# Initialize a markdown stream object
md = ui.MarkdownStream("shiny_readme")

# Display the stream UI in a card
with ui.card(height="400px", class_="mt-3", full_screen=True):
    ui.card_header("Shiny README.md")
    md.ui()


# Read in the README.md file from the py-shiny repository
readme = requests.get(
    "https://raw.githubusercontent.com/posit-dev/py-shiny/refs/heads/main/README.md"
)
readme_chunks = readme.text.replace("\n", " \n ").split(" ")


# Generate words from the README.md file (with a small delay)
async def chunk_generator():
    for chunk in readme_chunks:
        if not session.is_stub_session():
            await asyncio.sleep(0.02)
        yield chunk + " "


@reactive.effect
async def _():
    await md.stream(chunk_generator())

Methods

Name	Description
ui	Create a UI element for this MarkdownStream.

ui

express.ui.MarkdownStream.ui(
    content='',
    content_type='markdown',
    auto_scroll=True,
    width='min(680px, 100%)',
    height='auto',
)

Create a UI element for this MarkdownStream.

Parameters

content : TagChild = ''

A string of content to display before any streaming occurs. When content_type is Markdown or HTML, it may also be UI element(s) such as input and output bindings.

content_type : StreamingContentType = 'markdown'

The content type. Default is "markdown" (specifically, CommonMark). Supported content types include: - "markdown": markdown text, specifically CommonMark - "html": for rendering HTML content. - "text": for plain text. - "semi-markdown": for rendering markdown, but with HTML tags escaped.

auto_scroll : bool = True

Whether to automatically scroll to the bottom of a scrollable container when new content is added. Default is True.

width : CssUnit = 'min(680px, 100%)'

The width of the UI element.

height : CssUnit = 'auto'

The height of the UI element.

Returns

: Tag

A UI element for locating the MarkdownStream in the app.