How to download a PDF file in a Shiny app

Question

I have one PDF in the www directory of my shiny app. I would like that file to be available for download. How can i do that.

The download example works well, but no idea to use it for PDF download from www directory.

## Only run examples in interactive R sessions
if (interactive()) {

ui <- fluidPage(
  downloadLink("downloadData", "Download")
)

server <- function(input, output) {
  # Our dataset
  data <- mtcars

  output$downloadData <- downloadHandler(
    filename = function() {
      paste("data-", Sys.Date(), ".csv", sep="")
    },
    content = function(file) {
      write.csv(data, file)
    }
  )
}

shinyApp(ui, server)
}

Answer 1

If the file is in the www folder then you simply have to provide a link to it in the UI

... (in UI)
  tags$a("Click here to get the PDF", href="your-pdf-name.pdf")
...

If the filename is not known at start time then use uiOutput/renderUI and set rv$filename to the filename when you generate it.

... (in UI)
  uiOutput("dlURL")
...


... (in server)
  rv <- reactiveValues(filename="")

  output$dlURL <- renderUI({
    tags$a("Click here to get the file", href=rv$filename)
  })
...