Shiny

library(whereami)

Using whereami with shiny is simple. Place cat_where(whereami()) anywhere in a shiny command and every time the rendering application hits the line it will print to console indicating which line has been hit accompanied by a counter.

── Running renderPlot(...) at shiny.R#15 (1) ───────────────────────────────────────────
── Running renderPlot(...) at shiny.R#15 (2) ───────────────────────────────────────────

Here is an example of a simple app that uses whereami in the renderPlot chunk.

# Global variables can go here
n <- 200


# Define the UI
ui <- bootstrapPage(
  numericInput('n', 'Number of obs', n),
  plotOutput('plot')
)


# Define the server code
server <- function(input, output) {
  output$plot <- renderPlot({
    cat_where(whereami())
    hist(runif(input$n))
  })
}

# Return a Shiny app object
shinyApp(ui = ui, server = server)