In RStudio, select File | New File | Shiny Web App:

Enter the following code in app.R:

# Packt: Big Data Analytics 
# Chapter 8 Tutorial 
 
library(shiny) 
library(shinydashboard) 
library(data.table) 
library(DT) 
library(shinyjs) 
 
 
cms_factor_dt<- readRDS("~/r/rulespackt/cms_factor_dt.rds") 
cms_rules_dt<- readRDS("~/r/rulespackt/cms_rules_dt.rds") 
 
# Define UI for application that draws a histogram 
ui<- dashboardPage (skin="green",    
dashboardHeader(title = "Apriori Algorithm"), 
dashboardSidebar( 
useShinyjs(), 
sidebarMenu( 
uiOutput("company"), 
uiOutput("searchlhs"), 
uiOutput("searchrhs"), 
uiOutput("support2"), 
uiOutput("confidence"), 
uiOutput("lift"), 
downloadButton('downloadMatchingRules', "Download Rules") 
 
         ) 
),dashboardBody( 
tags$head( 
tags$link(rel = "stylesheet", type = "text/css", href = "packt2.css"), 
tags$link(rel = "stylesheet", type = "text/css", href = "//fonts.googleapis.com/css?family=Fanwood+Text"), 
tags$link(rel = "stylesheet", type = "text/css", href = "//fonts.googleapis.com/css?family=Varela"), 
tags$link(rel = "stylesheet", type = "text/css", href = "fonts.css"), 
 
tags$style(type="text/css", "select { max-width: 200px; }"), 
tags$style(type="text/css", "textarea { max-width: 185px; }"), 
tags$style(type="text/css", ".jslider { max-width: 200px; }"), 
tags$style(type='text/css', ".well { max-width: 250px; padding: 10px; font-size: 8px}"), 
tags$style(type='text/css', ".span4 { max-width: 250px; }") 
 
         ), 
fluidRow( 
dataTableOutput("result") 
) 
       ), 
       title = "Aprior Algorithm" 
) 
 
# Define server logic required to draw a histogram 
server <- function(input, output, session) { 
 
  PLACEHOLDERLIST2 <- list( 
    placeholder = 'Select All', 
onInitialize = I('function() { this.setValue(""); }') 
  ) 
 
output$company<- renderUI({ 
datasetList<- c("Select All",as.character(unique(sort(cms_factor_dt$company)))) 
selectizeInput("company", "Select Company" ,  
datasetList, multiple = FALSE,options = PLACEHOLDERLIST2,selected="Select All") 
  }) 
 
output$searchlhs<- renderUI({ 
textInput("searchlhs", "Search LHS", placeholder = "Search") 
  }) 
 
output$searchrhs<- renderUI({ 
textInput("searchrhs", "Search RHS", placeholder = "Search") 
  }) 
 
  output$support2 <- renderUI({ 
sliderInput("support2", label = 'Support',min=0,max=0.04,value=0.01,step=0.005) 
  }) 
 
output$confidence<- renderUI({ 
sliderInput("confidence", label = 'Confidence',min=0,max=1,value=0.5) 
  }) 
 
output$lift<- renderUI({ 
sliderInput("lift", label = 'Lift',min=0,max=10,value=0.8) 
  }) 
 
dataInput<- reactive({ 
    print(input$support2) 
    print(input$company) 
    print(identical(input$company,"")) 
 
    temp <- cms_rules_dt[support > input$support2 & confidence >input$confidence& lift >input$lift] 
 
    if(!identical(input$searchlhs,"")){ 
searchTerm<- paste0("*",input$searchlhs,"*") 
      temp <- temp[LHS %like% searchTerm] 
    } 
 
    if(!identical(input$searchrhs,"")){ 
searchTerm<- paste0("*",input$searchrhs,"*") 
      temp <- temp[RHS %like% searchTerm] 
    } 
 
if(!identical(input$company,"Select All")){ 
      # print("HERE") 
      temp <- temp[grepl(input$company,rules)] 
    } 
    temp[,.(LHS,RHS,support,confidence,lift)] 
  }) 
 
output$downloadMatchingRules<- downloadHandler( 
    filename = "Rules.csv", 
    content = function(file) { 
      write.csv(dataInput(), file, row.names=FALSE) 
    } 
  ) 
 
output$result<- renderDataTable({ 
    z = dataInput() 
    if (nrow(z) == 0) { 
      z <- data.table("LHS" = '', "RHS"='', "Support"='', "Confidence"='', "Lift" = '') 
    } 
setnames(z, c("LHS", "RHS", "Support", "Confidence", "Lift")) 
datatable(z,options = list(scrollX = TRUE)) 
  }) 
 
}  shinyApp(ui = ui, server = server)

The following image shows the code being copied and saved in a file called app.R.