Shiny reactive dataset within observeEvent - r

Question

I have a very simple app which fails. The reason it fails is that the reactive dataset is available solely within the observeEvent function but not outside. I use observeEvent to get datasets from two different sources wrangled. For this example I simply used cbind. My actual code is much more complicated.
This is a logical / syntax related problem but all my searching came up short. In essence I want merged_data() to be available for all parts of the app.
Minimum repr example - this fails because merged_data() is not available outside of the ObserveEvent.
library(shiny)
library(shinyjs)
library(DT)
# Define UI for application that draws a histogram
ui <- fluidPage(
# Application title
titlePanel("testing 1 2 3"),
# Sidebar with a slider input for number of bins
sidebarLayout(
sidebarPanel(
),
# Show a plot of the generated distribution
mainPanel(
fluidRow(
column(width = 2,
offset = 0,
align = "center",
actionButton(inputId = "fetch_data_inputId",
label = "data")
) #column
,
column(width = 10,
offset = 0,
align = "center",
DT::dataTableOutput("DT1")
) #column
)#fluidrow
)
)
)
# Define server logic required to draw a histogram
server <- function(input, output,session) {
observeEvent(input$fetch_data_inputId, {
req(iris)
button_data <- colnames(iris)
merged_data <- reactive({
if( !is.null(cbind(iris[,1:4],iris3))) {
cbind(iris[,1:4],iris3)
} else {NULL}
})
}) #observeevent
output$DT1 <- renderDataTable({#
rendered_table <- merged_data()
DT::datatable(rendered_table)
})
}
# Run the application
shinyApp(ui = ui, server = server)
Minimum repr example - this works because the datatable is created within the ObserveEvent.
library(shiny)
library(shinyjs)
library(DT)
# Define UI for application that draws a histogram
ui <- fluidPage(
# Application title
titlePanel("testing 1 2 3"),
# Sidebar with a slider input for number of bins
sidebarLayout(
sidebarPanel(
),
# Show a plot of the generated distribution
mainPanel(
fluidRow(
column(width = 2,
offset = 0,
align = "center",
actionButton(inputId = "fetch_data_inputId",
label = "data")
) #column
,
column(width = 10,
offset = 0,
align = "center",
DT::dataTableOutput("DT1")
) #column
)#fluidrow
)
)
)
# Define server logic required to draw a histogram
server <- function(input, output,session) {
observeEvent(input$fetch_data_inputId, {
req(iris)
button_data <- colnames(iris)
merged_data <- reactive({
if( !is.null(cbind(iris[,1:4],iris3))) {
cbind(iris[,1:4],iris3)
} else {NULL}
})
output$DT1 <- renderDataTable({#
rendered_table <- merged_data()
DT::datatable(rendered_table)
})
}) #observeevent
}
# Run the application
shinyApp(ui = ui, server = server)
What I really need is for the reactive dataset to continue being created within observeEvent but to be accessible outside of the ObserveEvent environment so that i use it in other parts of the app, but I suspect it's the wrong approach. So anything that works would be great.

Answer 1

library(shiny)
library(shinyjs)
library(DT)
# Define UI for application that draws a histogram
ui <- fluidPage(
# Application title
titlePanel("testing 1 2 3"),
# Sidebar with a slider input for number of bins
sidebarLayout(
sidebarPanel(
),
# Show a plot of the generated distribution
mainPanel(
fluidRow(
column(width = 2,
offset = 0,
align = "center",
actionButton(inputId = "fetch_data_inputId",
label = "data")
) #column
,
column(width = 10,
offset = 0,
align = "center",
DT::dataTableOutput("DT1")
) #column
)#fluidrow
)
)
)
# Define server logic required to draw a histogram
server <- function(input, output,session) {
merged_data <- eventReactive(input$fetch_data_inputId, {
req(iris)
button_data <- colnames(iris)
if( !is.null(cbind(iris[,1:4],iris3))) {
cbind(iris[,1:4],iris3)
} else {NULL}
}) #eventReactive
output$DT1 <- renderDataTable({#
rendered_table <- merged_data()
DT::datatable(rendered_table)
})
}
# Run the application
shinyApp(ui = ui, server = server)