Shiny R download zip file error

1,517 views
Skip to first unread message

tao hong

unread,
Nov 21, 2014, 1:33:31 PM11/21/14
to shiny-...@googlegroups.com
I am sorry if this too simple... I need to zip a number of generated pdfs for uses to download. I tried to use `Zip` function, but failed with error:

    Warning: running command '"zip" -r9X "pdfs.zip" "plot_1.pdf" "plot_2.pdf" "plot_3.pdf" "plot_4.pdf" "plot_5.pdf" ' had status 127
    Error opening file: 2
    Error reading: 6




UI.R

library(shiny)

shinyUI(fluidPage(
  singleton(tags$head(HTML(
'
  <script type="text/javascript">
    $(document).ready(function() {
      // disable download at startup. data_file is the id of the downloadButton
      $("#data_file").attr("disabled", "true").attr("onclick", "return false;");

      Shiny.addCustomMessageHandler("download_ready", function(message) {
        $("#data_file").removeAttr("disabled").removeAttr("onclick").html(
          "<i class=\\"fa fa-download\\"></i>Download " + message.fileSize + " ");
      });
    })
  </script>
'
))),
  tabsetPanel(
    tabPanel('Data download example',
      actionButton("start_proc", h5("Click to start processing data")),
      hr(),

      downloadButton("data_file"),
      helpText("Download will be available once the processing is completed.")
    )
  )
))

Server UI.R

library(shiny)

get_a_pdf_plot <- function(my_i){
      pdf(paste("plot_", my_i, sep=""))
      plot(1:my_i*5, 1:my_i*5,
           xlim = c(1, my_i*5),
           ylim = c(1, my_i*5),
           main = paste("1:", my_i, sep = ""))
      dev.off()
}


shinyServer(function(input, output, session) {

  observe({
    if (input$start_proc > 0) {
      Sys.sleep(2)
      session$sendCustomMessage("download_ready", list(fileSize= "Ready"))
    }
  })

  output$data_file <- downloadHandler(
       filename = 'pdfs.zip',
       content = function(fname) {
        fs <- c()
        tmpdir <- tempdir()
        setwd(tempdir())
        print (tempdir())

        for (i in c(1,2,3,4,5)) {
          path <- paste("plot_", i, ".pdf", sep="")
          fs <- c(fs, path)
          get_a_pdf_plot(i)
        }
        print (fs)
        zip(zipfile="pdfs.zip", files=fs)
       }
  )
})

tao hong

unread,
Nov 21, 2014, 2:52:03 PM11/21/14
to shiny-...@googlegroups.com
Just an update.  After using the below server.R, I can see all the files "plot_1.pdf" "plot_2.pdf" "plot_3.pdf" "plot_4.pdf" "plot_5.pdf", and "pdfs.zip" in the temp folder, but I just could not download it...

library(shiny)

get_a_pdf_plot <- function(my_i){
      pdf(paste("plot_", my_i, ".pdf", sep=""))
        plot(1:my_i*5, 1:my_i*5,
             xlim = c(1, my_i*5),
             ylim = c(1, my_i*5),
             main = paste("1:", my_i, sep = ""))
      dev.off()
}


shinyServer(function(input, output, session) {

  observe({
    if (input$start_proc > 0) {
      Sys.sleep(2)
      session$sendCustomMessage("download_ready", list(fileSize= "Ready"))
    }
  })

 output$data_file <- downloadHandler(
    filename = 'pdfs.zip',
    content = function(fname) {
      fs <- c()
      tmpdir <- tempdir()
      setwd(tempdir())
      print (tempdir())

      for (i in c(1,2,3,4,5)) {
        path <- paste("plot_", i, ".pdf", sep="")
        fs <- c(fs, path)
        get_a_pdf_plot(i)
      }
      print (fs)
      zip(zipfile=fname, files=fs)
    },
    contentType = "application/zip"
  )
})
 
 

tao hong

unread,
Nov 21, 2014, 3:13:40 PM11/21/14
to shiny-...@googlegroups.com
Problem fixed. Inspired by


   if (file.exists(paste0(fname, ".zip")))
    file.rename(paste0(fname, ".zip"), fname)  
Reply all
Reply to author
Forward
0 new messages