Shiny app promises works locally but not on shiny server

Posit Professional & Hosted Products shinyapps.io
,
1

I am struggling to debug my shiny app that has been deployed on the shiny server. It works fine locally, and it correctly deploys to the server but when I try to click the action button to return a get request it disconnects from the server. I think it has something to do with the promises in my code.
Here is the log I am getting from shiny server:

  85: promiseDomain$onThen
  84: action
  77: promise
  76: promise$then
  75: then
  74: %...>%
  73: getFile
  72: observeEventHandler
   1: runApp

And the code is something like this:

library(ggplot2)
library(dplyr)
library(lubridate)
library(promises)
library(future)
library(httr)

plan(multisession)

ColombiaStations <- c("541853724", "12345678")
source("./qc_functions.R")

ui <- shinyUI(fluidPage(
  title = "CSV Service",
Panel(
      selectInput("station", "Pick a station", choices = ColombiaStations),
      actionButton('getStationData', 'Get station data', 
    ) 
  )
)

server <- function(input, session, output){session$onSessionEnded(stopApp)
  
  observeEvent(input$getStationData, getFile(input$station))
}

shinyApp(ui, server)


**qc_functions.R**

getFile<- function(station) {

  urlCSV <- paste0("http://url-where-the-data-is",station)
  data <- future(GET(urlCSV)) %...>% cleanFile()

}

cleanFile <- function(response) {

  data <- content(response)
  write.csv(data, file="output.csv")
}

Note that this is a simplified version, and in reality I am cleaning up the file in the cleanFile function. Just wondering what's going wrong here?

Thanks

2

your problem is almost certianly in your url/data as this app I adapted from your partial example works fine for me

library(ggplot2)
library(dplyr)
library(lubridate)
library(promises)
library(future)
library(httr)
library(shiny)
library(shinyWidgets)

plan(multisession)

ColombiaStations <- c("541853724", "12345678")


getFile<- function(station) {
  cat("enter getFile with ",station,"\n")
  urlCSV <- "https://people.sc.fsu.edu/~jburkardt/data/csv/addresses.csv"
  data <- future(GET(urlCSV)) %...>% cleanFile()
  cat("ending getFile\n")
  data
}

cleanFile <- function(response) {
  cat("enter cleanFile\n")
  data <- content(response)
  cat("got content response\n")
  write.csv(data, file="output.csv")
  cat("written output, end CleanFile\n")
}

ui <- shinyUI(fluidPage(
  title = "CSV Service",
  shinyWidgets::panel(
    selectInput("station", "Pick a station", choices = ColombiaStations),
    actionButton('getStationData', 'Get station data', 
    ) 
  )
))

server <- function(input, session, output){session$onSessionEnded(stopApp)
  
  observeEvent(input$getStationData, {
    cat("button pressed with ",input$station, " will getFile")
    getFile(input$station)})
    cat("end button press event\n")
}

shinyApp(ui, server)