Request: Starting AppDriver in a custom URL for testing bookmarking

[zsigmas]

Hi all, I have not yet found a direct way of testing bookmarking. This is relevant when creating modules that you want to guarantee will save and restore bookmarks correctly.

One possibility would be to include a parameter in the AppDriver$new method:

app <- appDriver$new(appObject, query_args = "/?inputs_&n=10"

[schloerke]

For now, you can start your app in a background process and provide the url directly.

Something like..

# Untested code!

# Start app in background process given the port value
port <- httpuv::randomPort()
app_bg <- callr::r_bg(
  function(port) {
    appObject <- make_app_object()
    shiny::runApp(
      appObject,
      port = port,
      test.mode = TRUE
    )
  },
  list(port = port),
  stderr = "|"
)
withr::defer({ app_bg$kill() })

# Wait until the app is ready
for (i in 1:100) {
  if (pingr::is_up("127.0.0.1", 12345)) {
    break
  }
  Sys.sleep(0.2)
}

# Create bookmark url
app_url <- paste0("http://127.0.0.1:", port, "/?inputs_n=10")

# Use url value
app <- appDriver$new(app_url)

# Test like normal

While not as easy as a parameter, it can be wrapped up into a method. Will probably need to adjust the {withr} call to withr::defer({ app_bg$kill() }, envir = rlang::caller_env())

[zsigmas]

Thanks a lot!

[zsigmas]

Maybe a simpler solution for this problem could be:

(notice I have corrected some typos in the URL from the previous response)

bg_app <- shinytest2::AppDriver$new(app_dir = "my/shiny/app")
bg_app_url <- bg_app$get_url()
app<- shinytest2::AppDriver$new(paste0(bg_app_url, "?_inputs_&n=10"))

This delegates all the app launching process to shinytest2::AppDriver$new

Unfortunately, this (as well as the approach proposed in #219 (comment)) has the following problem:

bg_app <- shinytest2::AppDriver$new(app_dir = "my/shiny/app")
bg_app_url <- bg_app$get_url() # Assume that bg_app_url is http://127.0.0.1:1234
app<- shinytest2::AppDriver$new(paste0(bg_app_url, "/?inputs_n=10"))
app$get_url(shinytest2::AppDriver$new(paste0(bg_app_url, "?_inputs_&n=10"))
# [1] http://127.0.0.1:1234/?_inputs_=&n=10
# Notice the equal following '?_inputs_'

This breaks any attempt to include bookmarking parameters in the url.

I was able to pinpoint the problem to:

shinytest2/R/R6-helper.R

Line 60 in 29c7a6b

private$url <- httr::build_url(res)

I will report this in a different issue that links here to separate it from this enhancement request.

[schloerke]

What a wonderful solution!

bg_app <- shinytest2::AppDriver$new(app_dir = "my/shiny/app")
bg_app_url <- bg_app$get_url()
app<- shinytest2::AppDriver$new(paste0(bg_app_url, "?_inputs_&n=10"))

With this not being too terrible to have the user implement, (for now) I'm going to just make it a FAQ entry with your solution.

[schloerke]

The issues with _inputs_ != _inputs= has been addressed in #222