How to create a reactive component with an editable DT

Hi all,

I am trying to think of the best way to have a DT render in my shiny app using default data (e.g. iris), but also allow it up be editable. On the server side I feel like the data should be a reactive component (based on my mental model of observe vs. reactive), but I can't seem to get it working. The code below works, but it doesn't "feel" correct. Any experts see issues with my code?

The biggest problem is, since x isn't reactive, I have to add input$foo_cell_edit into any observeEvent(...) I want to update when the table is updated. If x() was reactive, I feel like that wouldn't be necessary.

library(shiny)
library(DT)

ui <- fluidPage(
  textOutput('txt'),
  dataTableOutput('foo')
)

server <- function(input, output, session) {
  x <- iris
  output$foo <- renderDataTable(datatable(x, editable = TRUE))
  
  proxy <- dataTableProxy('foo')
  
  observeEvent(input$foo_cell_edit, {
    x <<- editData(x, input$foo_cell_edit, proxy)
    
  })
  
  output$txt <- renderText({
    input$foo_cell_edit # necessary or text won't update on table edit
    sum(x[, 'Sepal.Length'])
    })
}

shinyApp(ui, server)