shiny-options {shiny} | R Documentation

## Global options for Shiny

### Description

There are a number of global options that affect Shiny's behavior. These can be set with (for example) `options(shiny.trace=TRUE)`.

### Details

shiny.launch.browser

  A boolean which controls the default behavior when an app is run. See `runApp` for more information.

shiny.port

  A port number that Shiny will listen on. See `runApp` for more information.

shiny.trace

  Print messages sent between the R server and the web browser client to the R console. This is useful for debugging. Possible values are `"send"` (only print messages sent to the client), `"recv"` (only print messages received by the server), `TRUE` (print all messages), or `FALSE` (default; don't print any of these messages).

shiny.autoreload

  If `TRUE` when a Shiny app is launched, the app directory will be continually monitored for changes to files that have the extensions: r, htm, html, js, css, png, jpg, jpeg, gif. If any changes are detected, all connected Shiny sessions are reloaded. This allows for fast feedback loops when tweaking Shiny UI.

  Since monitoring for changes is expensive (we simply poll for last modified times), this feature is intended only for development.

  You can customize the file patterns Shiny will monitor by setting the shiny.autoreload.pattern option. For example, to monitor only ui.R: `options(shiny.autoreload.pattern = glob2rx("ui.R"))`

  The default polling interval is 500 milliseconds. You can change this by setting e.g. `options(shiny.autoreload.interval = 2000)` (every two seconds).

shiny.reactlog

  If `TRUE`, enable logging of reactive events, which can be viewed later with the `showReactLog` function. This incurs a substantial performance penalty and should not be used in production.

shiny.usecairo

  This is used to disable graphical rendering by the Cairo package, if it is installed. See `plotPNG` for more information.

shiny.maxRequestSize

  This is a number which specifies the maximum web request size, which serves as a size limit for file uploads. If unset, the maximum request size defaults to 5MB.

shiny.suppressMissingContextError

  Normally, invoking a reactive outside of a reactive context (or `isolate()`) results in an error. If this is `TRUE`, don't error in these cases. This should only be used for debugging or demonstrations of reactivity at the console.

shiny.host

  The IP address that Shiny should listen on. See `runApp` for more information.

shiny.json.digits

  The number of digits to use when converting numbers to JSON format to send to the client web browser.

shiny.minified

  If this is `TRUE` or unset (the default), then Shiny will use minified JavaScript (`shiny.min.js`). If `FALSE`, then Shiny will use the un-minified JavaScript (`shiny.js`); this can be useful during development.

shiny.error

  This can be a function which is called when an error occurs. For example, `options(shiny.error=recover)` will result a the debugger prompt when an error occurs.

shiny.table.class

  CSS class names to use for tables.

shiny.deprecation.messages

  This controls whether messages for deprecated functions in Shiny will be printed. See `shinyDeprecated` for more information.

shiny.fullstacktrace

  Controls whether "pretty" or full stack traces are dumped to the console when errors occur during Shiny app execution. The default is `FALSE` (pretty stack traces).

shiny.stacktraceoffset

  If `TRUE`, then Shiny's printed stack traces will display srcrefs one line above their usual location. This is an arguably more intuitive arrangement for casual R users, as the name of a function appears next to the srcref where it is defined, rather than where it is currently being called from.

shiny.sanitize.errors

  If `TRUE`, then normal errors (i.e. errors not wrapped in `safeError`) won't show up in the app; a simple generic error message is printed instead (the error and strack trace printed to the console remain unchanged). The default is `FALSE` (unsanitized errors).If you want to sanitize errors in general, but you DO want a particular error `e` to get displayed to the user, then set this option to `TRUE` and use `stop(safeError(e))` for errors you want the user to see.

shiny.testmode

  If `TRUE`, then enable features for testing Shiny applications. If `FALSE` (the default), do not enable those features.

[Package shiny version 1.0.3 Index]