Download and Extract Shinylive Applications from URLs

Downloads and extracts Shinylive applications from various URL sources. The function can handle both standalone Shinylive applications and Quarto documents containing embedded Shinylive applications. It automatically detects the application type and extracts the necessary files.

Usage

peek_shinylive_app(url, output_dir = "converted_shiny_app")

Arguments

url

Character string. URL pointing to one of:

• A standalone Shinylive application (containing app.json)

• A directory containing app.json

• A Quarto document with embedded Shinylive applications

output_dir

Character string. Directory where the application files should be extracted. Defaults to "converted_shiny_app". Will be created if it doesn't exist.

Value

An object containing the extracted application information:

• For standalone apps: Object of class "standalone_shinylive_app"

• For Quarto documents: Object of class "quarto_shinylive_apps"

Both object types implement custom print methods that display:

• Application type (R or Python)

• Commands to run the application

• List of extracted files

• Output directory location

Details

The function follows these steps:

1. Downloads and analyzes the content at the provided URL

2. Determines if the content is a Quarto document or standalone application

3. For Quarto documents:

   • Extracts all embedded Shinylive applications

   • Creates separate directories for each application

4. For standalone applications:

   • Locates and validates the app.json file

   • Extracts all application files to the specified directory

URL Resolution

The function attempts several strategies to find app.json:

• Direct use of the provided URL

• Appending "app.json" to the URL

• Checking the parent directory

Error Handling

The function will error with informative messages if:

• The URL cannot be accessed

• No valid Shinylive application is found

• The app.json structure is invalid

See also

• peek_quarto_shinylive_app() for handling Quarto documents specifically

• peek_standalone_shinylive_app() for handling standalone applications

Examples

if (FALSE) { # interactive()
# Download a standalone Shinylive application
url <- "https://tutorials.thecoatlessprofessor.com/convert-shiny-app-r-shinylive/"

app <- peek_shinylive_app(url)

# Extract to a specific directory
app <- peek_shinylive_app(
  url,
  output_dir = "my_extracted_app"
)

# Download from a Quarto document
apps <- peek_shinylive_app("https://quarto-ext.github.io/shinylive/")
}