remove data file after plotting

[anny9699]

Hi,

Is there a way to remove the data file after plotting? I download the data to the machine where the shiny server is and generate some plots based on the data. After the app is exited or the plot is finished, I wish to remove the data file but don't know how to do it. Is there a way to do it? 

I tried to put the code inside function(input, output) right after renderPlot(), however it doesn't work. Does anyone have some suggestion?

Thanks a lot!

Anny

[Joe Cheng]

You probably don't want to delete it right after renderPlot; the plot will need to render again if the user resizes the browser window.

Add a "session" argument to your server function, i.e. "function(input, output, session)" then call something like this:

session$onSessionEnded(function() {

  if (!is.null(input$file1)) {

    file.remove(input$file1$datapath)

  }

})

though this will only delete the most recently uploaded file in this session, if any. If you want to delete more, keep a list of them as you go, and delete them all at the end.

--
You received this message because you are subscribed to the Google Groups "Shiny - Web Framework for R" group.
To unsubscribe from this group and stop receiving emails from it, send an email to shiny-discus...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/shiny-discuss/485af40b-856c-45d3-8d13-eb131bcc184e%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Anny Chen]

Thanks Joe for the explanation!

May I ask if I just want to delete them all at the end, shall I still need the "session" argument? Where shall I put the file.remove()? I tried to put it inside shinyServer() or outside shinyServer, but it seems not working.

Thanks a lot!

Anny

[Anny Chen]

Hi Joe,

I got it. I might still need the session elements to control.

Thanks a lot!

Anny

[Renger van Nieuwkoop]

Hi Joe

And if I want to delete a file during my session? I tried the following

fileInput('file2', 'Choose File') in the ui

and

   observeEvent(input$file2, {

      if (!is.null(input$file2)) {

        file.remove(input$file2$datapath)

        }

    })

in the server.R file, but this doesn't work.

I also tried with a seclectInput of a list of all files, but same problem.

Cheers

Renger

[Joe Cheng]

What doesn't work? Can you clarify what you're trying to do and what is going wrong?

--
You received this message because you are subscribed to the Google Groups "Shiny - Web Framework for R" group.

To unsubscribe from this group and stop receiving emails from it, send an email to shiny-discuss+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/shiny-discuss/1af8cd2d-5690-4763-bdd7-e2182853aa54%40googlegroups.com.

[Renger van Nieuwkoop]

In my shiny app users can upload several excel files to compare results, also results that are meant for testing. If the testing is over, these files should be deleted).

I read a list of files with

    list_of_excelfiles <- unlist(list.files(pattern = "xlsx"))

and want to have the possibility for the user to choose one of these files and delete it.

I tried with the following in the ui

      selectInput("delmodel", h4("File to delete:"),
             choices =  c("None", unique(as.character(list_of_excelfiles))),
             selectize = FALSE
      )

and then use the input$delmodel to get the chosen file deleted. That is why, I was looking at this post.

Cheers and thanks for looking at my question

Renger

On Friday, February 17, 2017 at 8:16:11 PM UTC+1, Joe Cheng [RStudio] wrote:

What doesn't work? Can you clarify what you're trying to do and what is going wrong?

On Fri, Feb 17, 2017 at 5:18 AM, Renger van Nieuwkoop <rvanni...@gmail.com> wrote:

Hi Joe

And if I want to delete a file during my session? I tried the following

fileInput('file2', 'Choose File') in the ui

and

   observeEvent(input$file2, {

      if (!is.null(input$file2)) {

        file.remove(input$file2$datapath)

        }

    })

in the server.R file, but this doesn't work.

I also tried with a seclectInput of a list of all files, but same problem.

Cheers

Renger

--
You received this message because you are subscribed to the Google Groups "Shiny - Web Framework for R" group.

To unsubscribe from this group and stop receiving emails from it, send an email to shiny-discus...@googlegroups.com.