Configure shinysnap for a session

Sets the app identity and the defaults used by snap_take() and snap_restore() for the current session. Calling it is optional: every snap_*() server function creates the per-session state on first use with the defaults below. Call it again to change the settings.

Usage

snap_enable(
  app = NULL,
  version = NULL,
  exclude = NULL,
  include = NULL,
  live_only = TRUE,
  use_restore_context = TRUE,
  verbose = FALSE,
  session = shiny::getDefaultReactiveDomain()
)

Arguments

app, version

The name and version of the app, written into every snapshot file. They default to the options shinysnap.app and shinysnap.version, which packaged apps can set once in .onLoad().

exclude, include

Character vectors of regular expressions matched against fully namespaced input ids. Matching exclude patterns are never captured; when include is given, only matching ids are. Ids excluded with shiny's setBookmarkExclude() are always honoured too.

live_only

Capture only inputs that are currently on the page (as reported by the client script), dropping values of inputs whose UI has been removed. Set to FALSE to capture every value shiny remembers.

use_restore_context

Prime shiny's restoreInput() mechanism during a restore, so that dynamic UI re-rendered during the restore is built with the restored values. Turn off only to debug.

verbose

Print messages about what is captured, dropped, and restored.

session

The Shiny session. Defaults to the current session.

Value

The session's controller, an R6 object, invisibly. It holds the snapshot configuration and is intended for internal use.

Examples

if (interactive()) {
  library(shiny)

  server <- function(input, output, session) {
    snap_enable(app = "myapp", version = "2.4.0", exclude = c("^btn_", "^nav_"))
  }
}