Interactive directory input in Shiny app (R)

This is a working example based on using the "webkitdirectory" attribute. At the moment the attribute is supported by Chrome, Opera and Safari (mobile and desktop) and it should be supported in Firefox 49 to be released in September. More about this here. It work with subdirectories also.

It requires using the tags keyword in ui.R. I have tested it by uploading three csv files each contaning three numbers separeted by a coma. Tested locally and on shinyapps.io with Chrome and Opera. This is the code:

ui.R

    library(shiny)
    library(DT)

    shinyUI(tagList(fluidPage(theme = "bootstrap.css",
                      includeScript("./www/text.js"),
                      titlePanel("Folder content upload"),

                      fluidRow(
                              column(4,
                                     wellPanel(
                                             tags$div(class="form-group shiny-input-container", 
                                                      tags$div(tags$label("File input")),
                                                      tags$div(tags$label("Choose folder", class="btn btn-primary",
                                                                          tags$input(id = "fileIn", webkitdirectory = TRUE, type = "file", style="display: none;", onchange="pressed()"))),
                                                      tags$label("No folder choosen", id = "noFile"),
                                                      tags$div(id="fileIn_progress", class="progress progress-striped active shiny-file-input-progress",
                                                               tags$div(class="progress-bar")
                                                      )     
                                             ),
                                             verbatimTextOutput("results")
                                     )
                              ),
                              column(8,
                                     tabsetPanel(
                                             tabPanel("Files table", dataTableOutput("tbl")),
                                             tabPanel("Files list", dataTableOutput("tbl2"))
                                     )
                              )
                      )
    ),
    HTML("<script type='text/javascript' src='getFolders.js'></script>")
    )

    )          

server.R

    library(shiny)
    library(ggplot2)
    library(DT)

    shinyServer(function(input, output, session) {
            df <- reactive({
                    inFiles <- input$fileIn
                    df <- data.frame()
                    if (is.null(inFiles))
                            return(NULL)
                    for (i in seq_along(inFiles$datapath)) {
                            tmp <- read.csv(inFiles$datapath[i], header = FALSE)  
                            df <- rbind(df, tmp)
                    }
                    df

            })
            output$tbl <- DT::renderDataTable(
                    df()
            )
            output$tbl2 <- DT::renderDataTable(
                    input$fileIn
            )
            output$results = renderPrint({
                    input$mydata
            })

    })

text.js

window.pressed = function(){
        var a = document.getElementById('fileIn');
        if(a.value === "")
        {
            noFile.innerHTML = "No folder choosen";
        }
        else
        {
            noFile.innerHTML = "";
        }
    };

getFolders.js

     document.getElementById("fileIn").addEventListener("change", function(e) {

            let files = e.target.files;
            var arr = new Array(files.length*2);
            for (let i=0; i<files.length; i++) {

            //console.log(files[i].webkitRelativePath);
            //console.log(files[i].name);
            arr[i] = files[i].webkitRelativePath;
            arr[i+files.length] = files[i].name;


            }

            Shiny.onInputChange("mydata", arr);

    });

Let me know if this helps.

Have you tried around with the shinyFiles package? There is a widget which lets you chose a directory. As output you get the path of that directory which you can in turn use to access the files. Here is an example how it works.

server

library(shiny)
library(shinyFiles)

shinyServer(function(input, output, session) {

  # dir
  shinyDirChoose(input, 'dir', roots = c(home = '~'), filetypes = c('', 'txt'))
  dir <- reactive(input$dir)
  output$dir <- renderPrint(dir())

  # path
  path <- reactive({
    home <- normalizePath("~")
    file.path(home, paste(unlist(dir()$path[-1]), collapse = .Platform$file.sep))
  })

  # files
  output$files <- renderPrint(list.files(path()))
}) 

ui

library(shiny)
library(shinyFiles)

shinyUI(fluidPage(sidebarLayout(

  sidebarPanel(
    shinyDirButton("dir", "Chose directory", "Upload")
  ),

  mainPanel(
    h4("output$dir"),
    verbatimTextOutput("dir"), br(),
    h4("Files in that dir"),
    verbatimTextOutput("files")
  )

))) 

Hope this helps.