Shinyapp runs slow when published

[RYann]

Hey!!
I created a very simple password generator and it worked perfect (well, as much as i managed) when tested from RStudio but when i uploaded it online it seems to function really bad /

What am i doing wrong?
https://psychisrael.shinyapps.io/passgen/

Code (single file):

library(shiny)
library(stringr)

pass <- function(pass_length=8,pass_num=10,use.signs=F,pin=NULL,signs="@#$^%"){
  if(use.signs){require("stringr")}
  set.seed(pin)
  pass.ops <- c(LETTERS,letters,0:9)
  signs=unlist(stringr::str_split(signs,pattern = ""))
  if(use.signs){pass.ops=c(pass.ops,signs)}
  password <- function(pass_length){
    paste(sample(pass.ops,
                 pass_length,T),collapse = "")}
  pass <- c()
  for(i in 1:pass_num){
    pass[i] <- password(pass_length)
  }
  return(data.frame(pass))
}
####
# Define UI for application
ui <- fluidPage(
    # Application title
    titlePanel("Password Generator"),

    sidebarLayout(
        sidebarPanel(
            sliderInput("passlength",
                        label = "Number of characters",
                        min = 4,
                        max = 30,
                        value = 8),

            numericInput("pass_num",
                         label = "Passwords to generate",
                         value = 5,min = 5,max=50,step=5),

            checkboxInput("signs",label = "Use symbols"),
            conditionalPanel("input.signs==TRUE",
                             textInput("sign_examp",label = "Symbols:",
                                       value ="!@#$%^&*.~`;")),
            downloadButton("download",
                           "Download passwords",
                           icon("lock"))   ),

        mainPanel(
           tableOutput("final_pass")        )    )   )

# Define server logic
server <- function(input, output) {
    x <- reactive({
      pass(pass_length = input$passlength,
           pass_num = input$pass_num,
           use.signs= input$signs,
           signs = input$sign_examp)
    })
    output$final_pass <- renderTable({x()})

    output$download <- downloadHandler(
      filename = function(){
        paste("pass",Sys.Date(),".csv",sep = "")
      },
      content = function(file){
        write.csv(x(),file,row.names = F)      }    )   }

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

[agus]

Hi!

Taking a quick glance at your code, it seems that a good place to start would be to remove this line:
if(use.signs){require("stringr")} , as you have already loaded this pkg on app start-up (and this will run everytime you call your pass() function when use.signs is TRUE).

HTH

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