Shiny App.. wordcloud

.gitignore

*.png
rsconnect/*

readme.md

A shiny app which lets you make a wordcloud and download the image (png) and the freq of words (csv). To know more head over to - wordcloud

DESCRIPTION

Title: Wordcloud
Author: TrigonaMinima
AuthorUrl: http://trigonaminima.github.io/

server.R

library(shiny)
library(wordcloud)
library(tm)
library(SnowballC)
# This above package is loaded by the tm by default but is not installed
# when the above packages were being installed
# so naturally shinyapp.io doesn't install this too.
# So, it is explicitly loaded here to be installed by the shinyapps server.

shinyServer(function(input, output) {

  datainput <- reactive({

    # Outputs a helpful message when neither text is entered nor
    # the text file uploaded.
    validate(
      need((input$text != "") || (!is.null(input$file)),
        "Please give me some text to work upon!"
      )
    )

    # If text input is not empty then get the corpus
    # else load text from the text file uploaded.
    # case of both text box and file uploader being empty was
    # covered by the above validate function.
    if (nchar(input$text) > 0){
      words <- Corpus(VectorSource(input$text))
    }
    else if (!is.null(input$file)){
      a <- input$file$datapath
      a <- substr(a, 1, nchar(a) - 1)
      words <- Corpus(DirSource(a))
    }

    # Cleaning & normalizing the corpus.
    words <- tm_map(words, stripWhitespace)
    words <- tm_map(words, content_transformer(tolower))
    words <- tm_map(words, removeWords, stopwords("SMART"))
    words <- tm_map(words, removeNumbers)
    words <- tm_map(words, removePunctuation)
    })

  # Reactive element to transform the data on the basis of
  # (de)selection of checkbox3 in ui.R
  finalinput <- reactive({
    if (input$checkbox3) datainput <- tm_map(datainput(), stemDocument)
    datainput()
    })

  # Reactive element to transform the data on the basis of
  # (de)selection of checkbox2 in ui.R
  asdas <- reactive({
    if (input$checkbox2) wordcloud_rep <- repeatable(wordcloud)
    else wordcloud_rep <- wordcloud
  })

  # Reactive element to generate the wordcloud and save it as a png
  # and return the filename.
  make_cloud <- reactive ({
    wordcloud_rep <- asdas()

    png("wordcloud.png", width=10, height=8, units="in", res=350)
    w <- wordcloud_rep(finalinput(),
      scale=c(5, 0.5),
      min.freq=input$slider1,
      max.words=input$slider2,
      random.order=input$checkbox4,
      rot.per=input$slider3,
      use.r.layout=FALSE,
      colors=brewer.pal(8, "Dark2"))
    dev.off()

    filename <- "wordcloud.png"
    })

  # Download handler for the image.
  output$wordcloud_img <- downloadHandler(
    filename = "wordcloud.png",
    content = function(cloud) {
      file.copy(make_cloud(), cloud)
    })

  # Download handler for the csv.
  output$freq_csv <- downloadHandler(
    filename = "freq.csv",
    content = function(freq) {
      a <- DocumentTermMatrix(finalinput())
      b <- sort(colSums(as.matrix(a)), decreasing=TRUE)
      write.csv(b, freq)
    })

  # Sending the wordcloud image to be rendered.
  output$wordcloud <- renderImage({
    list(src=make_cloud(), alt="Image being generated!", height=600)
  },
  deleteFile = FALSE)
})

ui.R

library(shiny)

shinyUI(fluidPage(
  # Title of the app
  titlePanel("Wordcloud!"),

  sidebarLayout(
    sidebarPanel(

      strong("Settings:"),

      # Checkboxes for the wordcloud settings
      checkboxInput("checkbox3", label = "Document stemming", value = TRUE),
      checkboxInput("checkbox4", label = "Random Order", value = FALSE),
      checkboxInput("checkbox2", label = "Repeatable", value = TRUE),

      # Slider input for frequency change
      sliderInput("slider1", "Minimum Frequency:",
        min = 1, max = 50, value = 5),

      # Slider input for rotation change
      sliderInput("slider3", "Rotation:",
        min = 0.0, max = 1.0, value = 0.35),

      # Slider input for number of words change
      sliderInput("slider2", "Max words:",
        min = 10, max = 1000, value = 100),

      # Text box to input the text
      textInput("text", "Text input:"),

      # Text file uploader
      fileInput("file", "Text file", accept=c("text/plain", ".txt"))),

    mainPanel(
      # Image download button
      downloadButton("wordcloud_img", "Download Image"),
      # CSV download button
      downloadButton("freq_csv", "Download Freq CSV"),
      # Wordcloud image rendered
      imageOutput("wordcloud"))
  )
))

Unable to process the results using a text file input. After I select a file, it shows Error: Empty Directory error