shinychat (version 0.3.0)

chat_restore: Add Shiny bookmarking for shinychat

Description

Adds Shiny bookmarking hooks to save and restore the ellmer chat client. Also restores chat messages from the history in the client.

If either bookmark_on_input or bookmark_on_response is TRUE, the Shiny App's bookmark will be automatically updated without showing a modal to the user.

Note: Only the client's chat state is saved/restored in the bookmark. If the client's state doesn't properly capture the chat's UI (i.e., a transformation is applied in-between receiving and displaying the message), then you may need to implement your own session$onRestore() (and possibly session$onBookmark) handler to restore any additional state.

To avoid restoring chat history from the client, you can ensure that the history is empty by calling client$set_turns(list()) before passing the client to chat_restore().

Usage

chat_restore(
  id,
  client,
  ...,
  bookmark_on_input = TRUE,
  bookmark_on_response = TRUE,
  session = getDefaultReactiveDomain()
)

Value

Returns nothing (invisible(NULL)).

Arguments

id

The ID of the chat element

client

The ellmer LLM chat client.

...

Used for future parameter expansion.

bookmark_on_input

A logical value determines if the bookmark should be updated when the user submits a message. Default is TRUE.

bookmark_on_response

A logical value determines if the bookmark should be updated when the response stream completes. Default is TRUE.

session

The Shiny session object

Examples

if (FALSE) { # interactive()
library(shiny)
library(bslib)
library(shinychat)

ui <- function(request) {
  page_fillable(
    chat_ui("chat", fill = TRUE)
  )
}

server <- function(input, output, session) {
  chat_client <- ellmer::chat_ollama(
    system_prompt = "Important: Always respond in a limerick",
    model = "qwen2.5-coder:1.5b",
    echo = TRUE
  )
  # Update bookmark to chat on user submission and completed response
  chat_restore("chat", chat_client)

  observeEvent(input$chat_user_input, {
    stream <- chat_client$stream_async(input$chat_user_input)
    chat_append("chat", stream)
  })
}

# Enable bookmarking!
shinyApp(ui, server, enableBookmarking = "server")
}