R Shiny 应用程序在 Linux 服务器上运行时下载文件

Question

I am working on a Shiny app which creates a URL based on user inputs and runs that URL using the browseURL() function. The URL downloads a csv file. The app needs to reside on a Linux server and when I try to run it from the server, it keeps giving me an error. When I run it on my machine, it opens Google Chrome (which is my default web browser) and downloads the csv file in the default "downloads" folder (which is what I expected it to do). Below is a simplified version of what I am trying to do. Could someone please help me figure out why it works on my machine but not on the Linux server? I just started this project and I don't know about Linux servers. The errors look like -

/usr/bin/xdg-open: 778: /usr/bin/xdg-open: www-browser: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: links2: not found
/usr/bin/xdg-open: 778: /usr/bin/xdg-open: elinks: not found

Any help is greatly appreciated.

library(shiny)
library(shinyWidgets)


ui <- fluidPage(
   
   # Application title
   titlePanel("Testing File Download on Linux Server"),
   
   
   sidebarLayout(
      sidebarPanel(
         textInput("SID","Specify SIDs", value = ""),
         actionBttn("goButton","Go!",color = "default",style = "unite",size = "lg")
      ),
      
      mainPanel()
      
           
   )
)


server <- function(input, output,session) {
 ts_info<-eventReactive(input$goButton,{
   TS_url<-paste("http://xyzserver&request=getList&station_no=",input$SID,"&format=csv&downloadfilename=testingdownload",sep="")

   return(TS_url)   
   

 })
 observe({
   browseURL(ts_info())
 }) 
   
}

# Run the application 
shinyApp(ui = ui, server = server)

Answer 1

By using browseURL you are asking to open a web browser on the server which obviously is not able to do because it's not the place to do this. The browser must be launched on your computer, not the server.

You can format and provide the url as an uiOutput

sidebarPanel(
         textInput("SID","Specify SIDs", value = ""),
         actionBttn("goButton","Go!",color = "default",style = "unite",size = "lg"),
         uiOutput("dlLink")
      ),

output$dlLink <- renderUI(tags$a(href=tsInfo(),"Download"))