Error when using file.choose() in Shiny Web App (deployed online)

Question

I am developing this shiny app that needs to push a local file to a FTP. I am having trouble with this.

I am using ftpUpload() to upload, and file.choose() to grab the file path:

ftpUpload(file.choose(new = FALSE), "ftp.com/Abc", userpwd)

This worked fine when I run the app in my local machine. However after I deploy it on the web, it doesn't work. It disconnects the serve.

I am thinking the issues are on file.choose() since the interactive file selection dialog wouldn't show up.

Does anyone know how to get the file.choose() working, or any other solutions?

Again I am trying to push a local file to an FTP server through an online Shiny App.

Update:

I have checked the log and I get this error:

Warning in file(what, "rb") : cannot open file 'xt': No such file or directory
Warning: Error in file: cannot open the connection

I am using a windows. and this error won't appear when I run the app locally from my RStudio

Could you include the server log that has the specific error to your run instance? — FAlonso
Do you know how to see specific error for an online app? This error only exists when the app is online. Currently when I try to call the function the whole app disconnected. — Kim HQ Jin
there will be a folder within ShinyApps in your server called 'logs'. Whenever an instance is initiated, a log would get generated which is a dump to what you see in your console when you run the app locally. Take a look at the file and update your question with the error message. — FAlonso

FAlonso FAlonso · Accepted Answer · 2019-10-02T03:44:56

A minimal working solution with fileInput.

# ui.R
ui <- fluidPage(
  sidebarLayout(
    sidebarPanel(
      fileInput("myFile", "Choose your File")
        )
    ),
    mainPanel(
    )
  )
)

# server.R
server <- function(input, output, session) {

   observeEvent(input$myFile,{
    selectedFile <- input$myFile

    if (is.null(selectedFile))
      return(NULL)

      # Your code
      ftpUpload(selectedFile$datapath, "ftp.com/Abc", userpwd)

  })


}

Hope this helps.

Error when using file.choose() in Shiny Web App (deployed online)

1 Answers