slRunRServer {shinylight}

Start a ShinyLight server which runs R that it is sent

Description

Start a ShinyLight server which runs R that it is sent

Usage

slRunRServer(
  permittedSymbols,
  appDir = NULL,
  host = "127.0.0.1",
  port = NULL,
  daemonize = FALSE,
  initialize = NULL
)

Arguments

permittedSymbols

List of symbols that are permitted in the R commands passed. Remember to include data, $ and <-.

appDir

Directory containing files to serve (for example system.file("www", package = "your-package"))

host

IP address to listen on, default is "127.0.0.1" (localhost). Use "0.0.0.0" to run in a docker container.

port

Internet port of the virtual server. If not defined, a random free port will be chosen and the browser will be opened to show the GUI.

daemonize

If TRUE, keep serving forever without returning. This is useful when called from RScript, to keep

initialize

A json string or list (that will be converted to a JSON string) to be passed to the JavaScript as initial data. The index.html must contain a line containing var shinylight_initial_data=, which will be replaced with code that sets shinylight_initial_data to this supplied JSON string.

Value

server object, unless daemonize is TRUE.

See Also

slServer for the more general form of this function, or slStop to stop a running server. shinylight.runR is the JavaScript function you need to call to pass R code from the browser to the server.

Examples

server <- slRunRServer(
  permitted = list("*"),
  port = 50053
)
# Normally we would use shinylight.js to send the function over
# and receive the result, not R and websocket.
ws <- websocket::WebSocket$new("ws://127.0.0.1:50053/x")
resultdata <- NULL
ws$onMessage(function(event) {
  resultdata <<- jsonlite::fromJSON(event$data)$result$data
})
ws$onOpen(function(event) {
  ws$send('{"method":"runR","params":{"Rcommand":"3 * 57"}}')
})
timeout = 30
while(is.null(resultdata) && 0 < timeout) {
  later::run_now()
  Sys.sleep(0.1)
  timeout <- timeout - 1
}
ws$close()
slStop(server)
stopifnot(resultdata == 171)  # 3 * 57 == 171
grDevices::png()  # workaround; you do not have to do this