Merge the uploaded csv with the current data frame in r shiny - r

Question

The example that I'm working with is the iris data. If the current data contains iris[1:15,], how can I upload a .csv file with more iris data and click a button to combine the uploaded data with the current data and save everything in one dataframe?
Here is what I have so far based on what I've read. I was able to create the fileInput and action button but I think my issue is with the reactive button. I'm not sure how to use it properly to achieve what I need.
library(shiny)
library(DT)
data1<-data.frame(iris[1:15,])
ui <- fluidPage(
sidebarLayout(
sidebarPanel(
fileInput("file1", "Choose CSV File",
accept = c(
"text/csv",
"text/comma-separated-values,text/plain",
".csv")
),
numericInput('num','Number of rows',value=10,min=0),
actionButton("update", "Combine Data")),
mainPanel(
tableOutput("table")
)
)
)
server <- function(input, output) {
output$table <- renderTable({
head(data1,n=input$num)
})
x<-reactive({
req(input$file1)
df_uploaded <- read.csv(input$file1$datapath,
header = input$header,
sep = input$sep,
quote = input$quote,
stringsAsFactors = FALSE)
data2<-data.frame(df_uploaded)
return(data2)
})
merged_data<-eventReactive(input$update,{
datam<-rbind.data.frame(data1,x())
return(datam)
})
# output$table <- renderTable({
# head(merged_data(),n=input$num)})
}
shinyApp(ui, server)
Thanks!

Answer 1

The main issue is that read.csv receiving invalid argument i.e. NULL for header, sep, quote as you don't have input$header, input$sep, input$quote in UI.
library(shiny)
library(DT)
data1<-data.frame(iris[1:15,])
ui <- fluidPage(
sidebarLayout(
sidebarPanel(
fileInput("file1", "Choose CSV File",
accept = c(
"text/csv",
"text/comma-separated-values,text/plain",
".csv")
),
numericInput('num','Number of rows',value=10,min=0),
actionButton("update", "Combine Data")),
mainPanel(
tableOutput("table")
)
)
)
server <- function(input, output) {
# output$table <- renderTable({
# head(data1,n=input$num)
# })
x<-reactive({
req(input$file1)
df_uploaded <- read.csv(input$file1$datapath,
#you don't have these variables in the UI, so they will raise an error
#header = input$header,
#sep = input$sep,
#quote = input$quote,
stringsAsFactors = FALSE)
#No need data2 and return(data2) as read.csv returns data.frame by default
#data2<-data.frame(df_uploaded)
#return(data2)
})
merged_data<-eventReactive(input$update,{
datam<-rbind.data.frame(data1, x())
return(datam)
})
output$table <- renderTable({
head(merged_data(), n=input$num)})
}
shinyApp(ui, server)