R shiny file输入大文件

Question

我对 R Shiny 的 fileInput 有一些问题。大小限制默认设置为 5MB。由于我必须处理的文件非常大 (>50GB)，我只需要文件的数据路径和/或名称。不幸的是，fileInput 想要上传完整的文件，或者至少它正在以某种方式加载文件，并在我达到 5MB 限制后告诉我文件太大。

如何只交出我的应用路径而不上传文件？

ui.R

library(shiny)

# Define UI ----
shinyUI(fluidPage(
h1("SAS Toolbox"),

tabsetPanel(
  tabPanel("SASFat",
     sidebarPanel(h2("Input:"),
        actionButton("runSASFat","Run Job",width="100%",icon("paper-plane"), 
        style="color: #fff; background-color: #337ab7; border-color: #2e6da4"),       

        wellPanel(
           #tags$style(".shiny-file-input-progress {display: none}"),
           fileInput("FEInp","Pfad FE input Deck:"), 
           fileInput("FERes","Pfad FE Results:") 
        ),
        wellPanel(
           checkboxGroupInput("options1","Auswertung:",c("Grundmaterial","Schweissnähte")),
           conditionalPanel(condition="$.inArray('Schweissnähte',input.options1) > -1", 
           sliderInput("filter", "Filter:", 0.75, min = 0, max = 1))
        ),
        wellPanel(
           radioButtons("solver", "Solver:", c("Ansys","Abaqus", "Optistruct")),
           conditionalPanel(condition="input.solver == 'Ansys'",selectInput("lic", "Lizenz",c("preppost","stba","meba"))) 
        ),
        wellPanel(
           checkboxGroupInput("options2","Optionen:",c("Schreibe LCFiles"))
        )
     ),
     mainPanel(br(),h2("Output:"),width="30%")
  ), 
  tabPanel("Nietauswertung"),
  tabPanel("Spannungskonzept EN12663")
  )
))

server.R

# Define server logic ----
shinyServer(function(input, output) {
  observeEvent(input$runSASFat, {
    FEInp <- input$FEInp
    FERes <- input$FERes
    opt1 <- input$options1 
    opt2 <- input$options2
    filter <- input$filter
    solver <- input$solver
    lic <- input$lic

    write(c(FEInp$datapath,FERes$datapath,opt1,opt2,filter,solver,lic),"ghhh.inp")
    })
})

提前致谢

迈克尔

Answer 1

感谢@MichaelBird 的示例。我修改了您的代码，让用户无需选择文件即可取消请求(您的应用程序在取消后崩溃):

顺便说一句，这只适用于托管 shiny 应用程序的 PC。

library(shiny)

ui <- fluidPage(
  titlePanel("Choosing a file example"),
  sidebarLayout(
    sidebarPanel(
      actionButton("filechoose",label = "Pick a file")
    ),
    mainPanel(
      textOutput("filechosen")
    )
  )
)

server <- function(input, output) {

  path <- reactiveVal(value = NULL)

  observeEvent(input$filechoose, {

    tryPath <- tryCatch(
      file.choose()
      , error = function(e){e}
    )

  if(inherits(tryPath, "error")){
    path(NULL)
  } else {
    path(tryPath)
  }

  })

  output$filechosen <- renderText({
    if(is.null(path())){
      "Nothing selected"
    } else {
      path()
    }
  })

}

shinyApp(ui = ui, server = server)

另一种方法是增加上传文件的最大大小:

By default, Shiny limits file uploads to 5MB per file. You can modify this limit by using the shiny.maxRequestSize option. For example, adding options(shiny.maxRequestSize = 30*1024^2) to the top of app.R would increase the limit to 30MB.

查看此 RStudio article .