inst/apps/194-reactlog-plot-cache-key/app.R

In rstudio/shinycoreci: CI Testing for shiny

library(shiny)
# Enable reactlog
library(reactlog)
reactlog_enable()

dataset <- reactiveVal(data.frame(x = rnorm(400), y = rnorm(400)))

ui <- fluidPage(
  # # Make sure body height does not change when taking screenshots
  # tags$style("body { min-height: 100vh; }"),

  sidebarLayout(
    sidebarPanel(
      sliderInput("n", "Number of points to display", 50, 400, 100, step = 50),
      actionButton("newdata", "Generate new data")
    ),
    mainPanel(
      plotOutput("plot")
    )
  ),
  ### start ui module
  reactlog_module_ui()
  ### end ui module
)

server <- function(input, output, session) {
  # When the newdata button is clicked, change the data set to new random data
  observeEvent(input$newdata, {
    dataset(data.frame(x = rnorm(400), y = rnorm(400)))
  })

  output$plot <- renderCachedPlot(
    {
      Sys.sleep(2) # Add an artificial delay
      d <- dataset()
      rownums <- seq_len(input$n)
      plot(d$x[rownums], d$y[rownums], xlim = range(d$x), ylim = range(d$y))
    },
    cacheKeyExpr = {
      list(input$n, dataset())
    }
  )

  ### start server module
  reactlog_module_server()
  ### end server module
}

shinyApp(ui, server)