R闪亮的应用程序错误shinyBS

Question

I have a ui as follows

library(shiny)

shinyUI(pageWithSidebar(
  headerPanel(tags$b(tags$em("Stock price testing for GBM"))),

  sidebarPanel(
    wellPanel(

      list(tags$head(tags$style("body {background-color: #E0F2F7; }"))),

      helpText(
      tags$div(
        tags$p("Welcome to this GBM test app that checks if geometrical brownian motion is a good model to predict stock prices. 
Input any stock ticker, whether it being an individual stock or an entire index, and click analysis to check if the assumptions of geometrical 
brownian motion holds for your ticker and range of dates."), 
        tags$p("Click",tags$a(href="https://uk.finance.yahoo.com/lookup", "here"),"to look for a symbol."))), 


      textInput("symb", "Symbol", "^FTSE"),
      bsAlert(inputId = "alert_anchor"),

      dateRangeInput("dates", 
                     "Date range",
                     start = "2015-01-01", 
                     end = as.character(Sys.Date())),
      textOutput("DateRange"),
      fluidRow(column(12,align="right",
      div(style="display:inline-block",submitButton("Analysis")))),
      fluidRow(column(12,tags$div(
        tags$p(" "),tags$p(" ")))),
      fluidRow(column(6,align="right",
      div(style="display:inline-block",downloadButton('downloadData','Download Data'))), column(6,align="right",
      div(style="display:inline-block",actionButton("action", label = "Help"))),width=6
      ))),





    ))))

and the server as

# server.R

"quantmod" %in% rownames(installed.packages())
if("quantmod" %in% rownames(installed.packages()) == FALSE) {install.packages("quantmod")}
"randtests" %in% rownames(installed.packages())
if("randtests" %in% rownames(installed.packages()) == FALSE) {install.packages("randtests")}
"fractal" %in% rownames(installed.packages())
if("fractal" %in% rownames(installed.packages()) == FALSE) {install.packages("fractal")}
"tseries" %in% rownames(installed.packages())
if("tseries" %in% rownames(installed.packages()) == FALSE) {install.packages("tseries")}
"car" %in% rownames(installed.packages())
if("car" %in% rownames(installed.packages()) == FALSE) {install.packages("car")}
"shinyBS" %in% rownames(installed.packages())
if("shinyBS" %in% rownames(installed.packages()) == FALSE) {install.packages("shinyBS")}
"rmarkdown" %in% rownames(installed.packages())
if("rmarkdown" %in% rownames(installed.packages()) == FALSE) {install.packages("rmarkdown")}

library("quantmod")
library("randtests") 
library("fractal")
library("tseries")
library("car")
library("shinyBS")


shinyServer(function(input, output,session) {
  getSymbols.warning4.0=FALSE
  options("getSymbols.warning4.0"=FALSE)

  dataInput <- reactive({
    data<-tryCatch({
      #if there is a bsAlert, close it
      closeAlert(session, "alert")
      #try to get the symbols
      getSymbols(input$symb, src = "yahoo", 
                 from = input$dates[1],
                 to = input$dates[2],
                 auto.assign = FALSE)},
      #if there is an error
      error=function(cond) {
        #create the bsAlert
        createAlert(session, inputId = "alert_anchor",
                    alertId="alert",
                    message = "Please enter a valid symbol and data range",
                    type = "info",
                    append="false", 
                    dismiss = FALSE
        )
        #return an empty string
        return("")
      })
    data
  })
  lg.ret<-reactive({
    validate(need(dataInput()!="","") )
    dailyReturn(dataInput(),type="log")

  })

  output$DateRange <- renderText({
    validate(
      need(input$dates[2] > input$dates[1], "End date is earlier than the start date")
    )
    lg.day.ret.vec<-lg.ret.vec()

      validate(
        need(length(lg.day.ret.vec) > 5, "Must choose a greater range of dates for accurate test results"))

    paste("Your date range is", 
          difftime(input$dates[2], input$dates[1], units="days"),
          "days")
  })

  lg.ret.vec<-reactive({
    validate(need(dataInput()!="","") )
    as.vector(dailyReturn(dataInput(),type="log"))

  })



})

However whenever i run the app from R, i always get this error ERROR: could not find function "bsAlert" . However to fix this error i just have to run library("shinyBS") in my console so that the library is opened. Seeing as I have this line already in my server, why do i always have to manually run that in my console? Is there a way so that I don't get this error anymore as the library will automatically load the user chooses to run the app.

Thanks

Answer 1

create a file global.R where you define the packages to be used on both ui.R and server.R

    #global.r
library("quantmod")
library("randtests") 
library("fractal")
library("tseries")
library("car")
library("shinyBS")