R - Shiny Conditional Input - r

Question

I am trying to get input choices dependent on previous input.
require(shiny)
require(dplyr)
dat <- data.frame(id1 = c(rep("A",5),rep("B",5)),
id2 = c(rep("C",3),rep("D",3),rep("E",4)),
id3 = c(rep("F",2),rep("G",3),rep("H",5)), stringsAsFactors=FALSE)
ui <- shinyUI(fluidPage(
sidebarPanel(
selectInput('id1', 'ID1', choices = unique(dat$id1)),
selectInput("id2", "ID2", choices = unique(dat$id2)),
selectInput("id3", "ID3", choices = unique(dat$id3))
)
)
)
server <- function(input, output,session) {
observeEvent(
{
input$id1
},{
input$id2
temp <- dat %>% filter(id1%in%input$id1)
updateSelectInput(session,"id2",choices = unique(temp$id2))
}
)
}
shinyApp(ui = ui, server = server)
This works for Input 1 and 2, however if i add another Input to observeEvent, the app chrashes. E.g:
server <- function(input, output,session) {
observeEvent(
{
input$id1
},{
input$id2
temp <- dat %>% filter(id1%in%input$id1)
updateSelectInput(session,"id2",choices = unique(temp$id2))
},{
input$id3
temp <- dat %>% filter(id1%in%input$id1 & id2%in%input$id2)
updateSelectInput(session,"id3",choices = unique(temp$id3))
}
)
}
How can I pass further Inputs to observeEvent ?

Answer 1

Update: I found a solution for the problem. I wrapped the Inputs in a reactive function, split the Output and passed it to the corresponding observeEvent functions.
server <- function(input, output,session) {
change <- reactive({
unlist(strsplit(paste(c(input$id1,input$id2,input$id3),collapse="|"),"|",fixed=TRUE))
})
observeEvent(input$id1,{
temp <- dat %>% filter(id1 %in% change()[1])
updateSelectInput(session,"id2",choices = unique(temp$id2))
}
)
observeEvent(input$id2,{
temp <- dat %>% filter(id1 %in% change()[1] & id2 %in% change()[2])
updateSelectInput(session,"id3",choices = unique(temp$id3))
}
)
}