R/shiny.R
In ymd526442121/Rproject_shiny: Web Application Framework for R
Defines functions
createUniqueId
toJSON
NS
.createOutputWriter
`$<-.shinyoutput`
`$.shinyoutput`
`[.shinyoutput`
`[<-.shinyoutput`
outputOptions
Documented in
NS
outputOptions
#' @include utils.R stack.R
NULL
#' Web Application Framework for R
#'
#' Shiny makes it incredibly easy to build interactive web applications with R.
#' Automatic "reactive" binding between inputs and outputs and extensive
#' pre-built widgets make it possible to build beautiful, responsive, and
#' powerful applications with minimal effort.
#'
#' The Shiny tutorial at \url{http://shiny.rstudio.com/tutorial/} explains
#' the framework in depth, walks you through building a simple application, and
#' includes extensive annotated examples.
#'
#' @seealso \link{shiny-options} for documentation about global options.
#'
#' @name shiny-package
#' @aliases shiny
#' @docType package
#' @import htmltools httpuv xtable digest R6 mime
NULL
# It's necessary to Depend on methods so Rscript doesn't fail. It's necessary
# to import(methods) in NAMESPACE so R CMD check doesn't complain. This
# approach isn't foolproof because Rscript -e pkgname::func() doesn't actually
# cause methods to be attached, but it's not a problem for shiny::runApp()
# since we call require(shiny) as part of loading the app.
#' @import methods
NULL
#' Global options for Shiny
#'
#' There are a number of global options that affect Shiny's behavior. These can
#' be set with (for example) \code{options(shiny.trace=TRUE)}.
#'
#' \describe{
#' \item{shiny.launch.browser}{A boolean which controls the default behavior
#' when an app is run. See \code{\link{runApp}} for more information.}
#' \item{shiny.port}{A port number that Shiny will listen on. See
#' \code{\link{runApp}} for more information.}
#' \item{shiny.trace}{If \code{TRUE}, all of the messages sent between the R
#' server and the web browser client will be printed on the console. This
#' is useful for debugging.}
#' \item{shiny.autoreload}{If \code{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:
#' \code{option(shiny.autoreload.pattern = glob2rx("ui.R"))}
#'
#' The default polling interval is 500 milliseconds. You can change this
#' by setting e.g. \code{option(shiny.autoreload.interval = 2000)} (every
#' two seconds).}
#' \item{shiny.reactlog}{If \code{TRUE}, enable logging of reactive events,
#' which can be viewed later with the \code{\link{showReactLog}} function.
#' This incurs a substantial performance penalty and should not be used in
#' production.}
#' \item{shiny.usecairo}{This is used to disable graphical rendering by the
#' Cairo package, if it is installed. See \code{\link{plotPNG}} for more
#' information.}
#' \item{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.}
#' \item{shiny.suppressMissingContextError}{Normally, invoking a reactive
#' outside of a reactive context (or \code{\link{isolate}()}) results in
#' an error. If this is \code{TRUE}, don't error in these cases. This
#' should only be used for debugging or demonstrations of reactivity at the
#' console.}
#' \item{shiny.host}{The IP address that Shiny should listen on. See
#' \code{\link{runApp}} for more information.}
#' \item{shiny.json.digits}{The number of digits to use when converting
#' numbers to JSON format to send to the client web browser.}
#' \item{shiny.minified}{If this is \code{TRUE} or unset (the default), then
#' Shiny will use minified JavaScript (\code{shiny.min.js}). If
#' \code{FALSE}, then Shiny will use the un-minified JavaScript
#' (\code{shiny.js}); this can be useful during development.}
#' \item{shiny.error}{This can be a function which is called when an error
#' occurs. For example, \code{options(shiny.error=recover)} will result a
#' the debugger prompt when an error occurs.}
#' \item{shiny.table.class}{CSS class names to use for tables.}
#' \item{shiny.deprecation.messages}{This controls whether messages for
#' deprecated functions in Shiny will be printed. See
#' \code{\link{shinyDeprecated}} for more information.}
#' \item{shiny.fullstacktrace}{Controls whether "pretty" or full stack traces
#' are dumped to the console when errors occur during Shiny app execution.
#' The default is \code{FALSE} (pretty stack traces).}
#' \item{shiny.stacktraceoffset}{If \code{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.}
#' \item{shiny.sanitize.errors}{If \code{TRUE}, then normal errors (i.e.
#' errors not wrapped in \code{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 \code{FALSE} (unsanitized
#' errors).If you want to sanitize errors in general, but you DO want a
#' particular error \code{e} to get displayed to the user, then set this option
#' to \code{TRUE} and use \code{stop(safeError(e))} for errors you want the
#' user to see.}
#' }
#' @name shiny-options
NULL
createUniqueId <- function(bytes, prefix = "", suffix = "") {
withPrivateSeed({
paste(
prefix,
paste(
format(as.hexmode(sample(256, bytes, replace = TRUE)-1), width=2),
collapse = ""),
suffix,
sep = ""
)
})
}
toJSON <- function(x, ..., dataframe = "columns", null = "null", na = "null",
auto_unbox = TRUE, digits = getOption("shiny.json.digits", 16),
use_signif = TRUE, force = TRUE, POSIXt = "ISO8601", UTC = TRUE,
rownames = FALSE, keep_vec_names = TRUE) {
# I(x) is so that length-1 atomic vectors get put in [].
jsonlite::toJSON(I(x), dataframe = dataframe, null = null, na = na,
auto_unbox = auto_unbox, digits = digits, use_signif = use_signif,
force = force, POSIXt = POSIXt, UTC = UTC, rownames = rownames,
keep_vec_names = keep_vec_names, json_verbatim = TRUE, ...)
}
# Call the workerId func with no args to get the worker id, and with an arg to
# set it.
#
# A worker ID is an opaque string that is passed in by the caller. The ID is
# added as a URL parameter (?w=<worker_id>) to any URLs that need to refer back
# to the app. This can be used as a hint for load balancers to direct requests
# to this particular process. Since the worker refers to a process, it's
# inherently global, and should never need to change.
workerId <- local({
.workerId <- NULL
function(value) {
if (missing(value)) {
.workerId
} else {
if (!is.null(.workerId)) {
if (!identical(value, .workerId)) {
warning("Ignoring workerId value--",
"it's already been set to a different value")
}
} else {
.workerId <<- value
}
}
}
})
#' Session object
#'
#' Shiny server functions can optionally include \code{session} as a parameter
#' (e.g. \code{function(input, output, session)}). The session object is an
#' environment that can be used to access information and functionality
#' relating to the session. The following list describes the items available
#' in the environment; they can be accessed using the \code{$} operator (for
#' example, \code{session$clientData$url_search}).
#'
#' @return
#' \item{clientData}{
#' A \code{\link{reactiveValues}} object that contains information about the client.
#' \itemize{
#' \item{\code{allowDataUriScheme} is a logical value that indicates whether
#' the browser is able to handle URIs that use the \code{data:} scheme.
#' }
#' \item{\code{pixelratio} reports the "device pixel ratio" from the web browser,
#' or 1 if none is reported. The value is 2 for Apple Retina displays.
#' }
#' \item{\code{singletons} - for internal use}
#' \item{\code{url_protocol}, \code{url_hostname}, \code{url_port},
#' \code{url_pathname}, \code{url_search}, and \code{url_hash_initial}
#' can be used to get the components of the URL that was requested by the
#' browser to load the Shiny app page. These values are from the
#' browser's perspective, so neither HTTP proxies nor Shiny Server will
#' affect these values. The \code{url_search} value may be used with
#' \code{\link{parseQueryString}} to access query string parameters.
#' }
#' }
#' \code{clientData} also contains information about each output.
#' \code{output_\var{outputId}_width} and \code{output_\var{outputId}_height}
#' give the dimensions (using \code{offsetWidth} and \code{offsetHeight}) of
#' the DOM element that is bound to \code{\var{outputId}}, and
#' \code{output_\var{outputId}_hidden} is a logical that indicates whether
#' the element is hidden. These values may be \code{NULL} if the output is
#' not bound.
#' }
#' \item{input}{
#' The session's \code{input} object (the same as is passed into the Shiny
#' server function as an argument).
#' }
#' \item{isClosed()}{A function that returns \code{TRUE} if the client has
#' disconnected.
#' }
#' \item{onEnded(callback)}{
#' Synonym for \code{onSessionEnded}.
#' }
#' \item{onFlush(func, once=TRUE)}{
#' Registers a function to be called before the next time (if \code{once=TRUE})
#' or every time (if \code{once=FALSE}) Shiny flushes the reactive system.
#' Returns a function that can be called with no arguments to cancel the
#' registration.
#' }
#' \item{onFlushed(func, once=TRUE)}{
#' Registers a function to be called after the next time (if \code{once=TRUE})
#' or every time (if \code{once=FALSE}) Shiny flushes the reactive system.
#' Returns a function that can be called with no arguments to cancel the
#' registration.
#' }
#' \item{onSessionEnded(callback)}{
#' Registers a function to be called after the client has disconnected.
#' Returns a function that can be called with no arguments to cancel the
#' registration.
#' }
#' \item{output}{
#' The session's \code{output} object (the same as is passed into the Shiny
#' server function as an argument).
#' }
#' \item{reactlog}{
#' For internal use.
#' }
#' \item{registerDataObj(name, data, filterFunc)}{
#' Publishes any R object as a URL endpoint that is unique to this session.
#' \code{name} must be a single element character vector; it will be used
#' to form part of the URL. \code{filterFunc} must be a function that takes
#' two arguments: \code{data} (the value that was passed into
#' \code{registerDataObj}) and \code{req} (an environment that implements
#' the Rook specification for HTTP requests). \code{filterFunc} will be
#' called with these values whenever an HTTP request is made to the URL
#' endpoint. The return value of \code{filterFunc} should be a Rook-style
#' response.
#' }
#' \item{reload()}{
#' The equivalent of hitting the browser's Reload button. Only works if the
#' session is actually connected.
#' }
#' \item{request}{
#' An environment that implements the Rook specification for HTTP requests.
#' This is the request that was used to initiate the websocket connection
#' (as opposed to the request that downloaded the web page for the app).
#' }
#' \item{allowReconnect(value)}{
#' If \code{value} is \code{TRUE} and run in a hosting environment (Shiny
#' Server or Connect) with reconnections enabled, then when the session ends
#' due to the network connection closing, the client will attempt to
#' reconnect to the server. If a reconnection is successful, the browser will
#' send all the current input values to the new session on the server, and
#' the server will recalculate any outputs and send them back to the client.
#' If \code{value} is \code{FALSE}, reconnections will be disabled (this is
#' the default state). If \code{"force"}, then the client browser will always
#' attempt to reconnect. The only reason to use \code{"force"} is for testing
#' on a local connection (without Shiny Server or Connect).
#' }
#' \item{sendCustomMessage(type, message)}{
#' Sends a custom message to the web page. \code{type} must be a
#' single-element character vector giving the type of message, while
#' \code{message} can be any jsonlite-encodable value. Custom messages
#' have no meaning to Shiny itself; they are used soley to convey information
#' to custom JavaScript logic in the browser. You can do this by adding
#' JavaScript code to the browser that calls
#' \code{Shiny.addCustomMessageHandler(type, function(message){...})}
#' as the page loads; the function you provide to
#' \code{addCustomMessageHandler} will be invoked each time
#' \code{sendCustomMessage} is called on the server.
#' }
#' \item{sendInputMessage(inputId, message)}{
#' Sends a message to an input on the session's client web page; if the input
#' is present and bound on the page at the time the message is received, then
#' the input binding object's \code{receiveMessage(el, message)} method will
#' be called. \code{sendInputMessage} should generally not be called directly
#' from Shiny apps, but through friendlier wrapper functions like
#' \code{\link{updateTextInput}}.
#' }
#' \item{ns(id)}{
#' Server-side version of \code{ns <- \link{NS}(id)}. If bare IDs need to be
#' explicitly namespaced for the current module, \code{session$ns("name")}
#' will return the fully-qualified ID.
#' }
#'
#' @name session
NULL
#' Namespaced IDs for inputs/outputs
#'
#' The \code{NS} function creates namespaced IDs out of bare IDs, by joining
#' them using \code{ns.sep} as the delimiter. It is intended for use in Shiny
#' modules. See \url{http://shiny.rstudio.com/articles/modules.html}.
#'
#' Shiny applications use IDs to identify inputs and outputs. These IDs must be
#' unique within an application, as accidentally using the same input/output ID
#' more than once will result in unexpected behavior. The traditional solution
#' for preventing name collisions is \emph{namespaces}; a namespace is to an ID
#' as a directory is to a file. Use the \code{NS} function to turn a bare ID
#' into a namespaced one, by combining them with \code{ns.sep} in between.
#'
#' @param namespace The character vector to use for the namespace. This can have
#' any length, though a single element is most common. Length 0 will cause the
#' \code{id} to be returned without a namespace, and length 2 will be
#' interpreted as multiple namespaces, in increasing order of specificity
#' (i.e. starting with the top-level namespace).
#' @param id The id string to be namespaced (optional).
#' @return If \code{id} is missing, returns a function that expects an id string
#' as its only argument and returns that id with the namespace prepended.
#' @seealso \url{http://shiny.rstudio.com/articles/modules.html}
#'
#' @export
NS <- function(namespace, id = NULL) {
if (missing(id)) {
function(id) {
paste(c(namespace, id), collapse = ns.sep)
}
} else {
paste(c(namespace, id), collapse = ns.sep)
}
}
#' @rdname NS
#' @export
ns.sep <- "-"
#' @include utils.R
ShinySession <- R6Class(
'ShinySession',
private = list(
# There are some private items with a leading "."; except for the dot, these
# items share a name with a public item.
websocket = 'ANY',
invalidatedOutputValues = 'Map',
invalidatedOutputErrors = 'Map',
inputMessageQueue = list(), # A list of inputMessages to send when flushed
.outputs = list(), # Keeps track of all the output observer objects
.outputOptions = list(), # Options for each of the output observer objects
progressKeys = 'character',
showcase = 'ANY',
fileUploadContext = 'FileUploadContext',
.input = 'ANY', # Internal ReactiveValues object for normal input sent from client
.clientData = 'ANY', # Internal ReactiveValues object for other data sent from the client
busyCount = 0L, # Number of observer callbacks that are pending. When 0, we are idle
closedCallbacks = 'Callbacks',
flushCallbacks = 'Callbacks',
flushedCallbacks = 'Callbacks',
inputReceivedCallbacks = 'Callbacks',
sendResponse = function(requestMsg, value) {
if (is.null(requestMsg$tag)) {
warning("Tried to send response for untagged message; method: ",
requestMsg$method)
return()
}
private$sendMessage(
response = list(tag = requestMsg$tag, value = value)
)
},
sendErrorResponse = function(requestMsg, error) {
if (is.null(requestMsg$tag))
return()
private$sendMessage(
response = list(tag = requestMsg$tag, error = error)
)
},
write = function(json) {
if (self$closed){
return()
}
if (isTRUE(getOption('shiny.trace')))
message('SEND ',
gsub('(?m)base64,[a-zA-Z0-9+/=]+','[base64 data]',json,perl=TRUE))
private$websocket$send(json)
},
sendMessage = function(...) {
# This function is a wrapper for $write
msg <- list(...)
if (anyUnnamed(msg)) {
stop("All arguments to sendMessage must be named.")
}
private$write(toJSON(msg))
},
getOutputOption = function(outputName, propertyName, defaultValue) {
opts <- private$.outputOptions[[outputName]]
if (is.null(opts))
return(defaultValue)
result <- opts[[propertyName]]
if (is.null(result))
return(defaultValue)
return(result)
},
shouldSuspend = function(name) {
# Find corresponding hidden state clientData variable, with the format
# "output_foo_hidden". (It comes from .clientdata_output_foo_hidden
# on the JS side)
# Some tricky stuff: instead of accessing names using input$names(),
# get the names directly via input$.values, to avoid triggering reactivity.
# Need to handle cases where the output object isn't actually used
# in the web page; in these cases, there's no output_foo_hidden flag,
# and hidden should be TRUE. In other words, NULL and TRUE should map to
# TRUE, FALSE should map to FALSE.
hidden <- private$.clientData$.values[[paste("output_", name, "_hidden",
sep="")]]
if (is.null(hidden)) hidden <- TRUE
return(hidden && private$getOutputOption(name, 'suspendWhenHidden', TRUE))
},
registerSessionEndCallbacks = function() {
# This is to be called from the initialization. It registers functions
# that are called when a session ends.
# Clear file upload directories, if present
self$onSessionEnded(private$fileUploadContext$rmUploadDirs)
}
),
public = list(
progressStack = 'Stack', # Stack of progress objects
input = 'reactivevalues', # Externally-usable S3 wrapper object for .input
output = 'ANY', # Externally-usable S3 wrapper object for .outputs
clientData = 'reactivevalues', # Externally-usable S3 wrapper object for .clientData
token = 'character', # Used to identify this instance in URLs
files = 'Map', # For keeping track of files sent to client
downloads = 'Map',
closed = logical(0),
request = 'ANY', # Websocket request object
singletons = character(0), # Tracks singleton HTML fragments sent to the page
user = NULL,
groups = NULL,
initialize = function(websocket) {
private$websocket <- websocket
self$closed <- FALSE
# TODO: Put file upload context in user/app-specific dir if possible
private$invalidatedOutputValues <- Map$new()
private$invalidatedOutputErrors <- Map$new()
private$fileUploadContext <- FileUploadContext$new()
private$closedCallbacks <- Callbacks$new()
private$flushCallbacks <- Callbacks$new()
private$flushedCallbacks <- Callbacks$new()
private$inputReceivedCallbacks <- Callbacks$new()
private$.input <- ReactiveValues$new()
private$.clientData <- ReactiveValues$new()
self$progressStack <- Stack$new()
self$files <- Map$new()
self$downloads <- Map$new()
self$input <- .createReactiveValues(private$.input, readonly=TRUE)
.setLabel(self$input, 'input')
self$clientData <- .createReactiveValues(private$.clientData, readonly=TRUE)
.setLabel(self$clientData, 'clientData')
self$output <- .createOutputWriter(self)
self$token <- createUniqueId(16)
private$.outputs <- list()
private$.outputOptions <- list()
private$registerSessionEndCallbacks()
if (!is.null(websocket$request$HTTP_SHINY_SERVER_CREDENTIALS)) {
try({
creds <- jsonlite::fromJSON(websocket$request$HTTP_SHINY_SERVER_CREDENTIALS)
self$user <- creds$user
self$groups <- creds$groups
}, silent=FALSE)
}
# session$request should throw an error if httpuv doesn't have
# websocket$request, but don't throw it until a caller actually
# tries to access session$request
delayedAssign('request', websocket$request, assign.env = self)
private$sendMessage(
config = list(
workerId = workerId(),
sessionId = self$token
)
)
},
makeScope = function(namespace) {
ns <- NS(namespace)
createSessionProxy(self,
input = .createReactiveValues(private$.input, readonly = TRUE, ns = ns),
output = .createOutputWriter(self, ns = ns),
sendInputMessage = function(inputId, message) {
.subset2(self, "sendInputMessage")(ns(inputId), message)
},
registerDataObj = function(name, data, filterFunc) {
.subset2(self, "registerDataObj")(ns(name), data, filterFunc)
},
ns = ns,
makeScope = function(namespace) {
self$makeScope(ns(namespace))
}
)
},
ns = function(id) {
NS(NULL, id)
},
onSessionEnded = function(sessionEndedCallback) {
"Registers the given callback to be invoked when the session is closed
(i.e. the connection to the client has been severed). The return value
is a function which unregisters the callback. If multiple callbacks are
registered, the order in which they are invoked is not guaranteed."
return(private$closedCallbacks$register(sessionEndedCallback))
},
onEnded = function(endedCallback) {
"Synonym for onSessionEnded"
return(self$onSessionEnded(endedCallback))
},
onInputReceived = function(callback) {
"Registers the given callback to be invoked when the session receives
new data from the client."
return(private$inputReceivedCallbacks$register(callback))
},
unhandledError = function(e) {
self$close()
},
close = function() {
if (!self$closed) {
private$websocket$close()
}
},
wsClosed = function() {
self$closed <- TRUE
for (output in private$.outputs) {
output$suspend()
}
# ..stacktraceon matches with the top-level ..stacktraceoff..
private$closedCallbacks$invoke(onError = printError, ..stacktraceon = TRUE)
flushReact()
lapply(appsByToken$values(), function(shinysession) {
shinysession$flushOutput()
NULL
})
},
isClosed = function() {
return(self$closed)
},
isEnded = function() {
return(self$isClosed())
},
setShowcase = function(value) {
private$showcase <- !is.null(value) && as.logical(value)
},
allowReconnect = function(value) {
if (!(identical(value, TRUE) || identical(value, FALSE) || identical(value, "force"))) {
stop('value must be TRUE, FALSE, or "force"')
}
private$write(toJSON(list(allowReconnect = value)))
},
defineOutput = function(name, func, label) {
"Binds an output generating function to this name. The function can either
take no parameters, or have named parameters for \\code{name} and
\\code{shinysession} (in the future this list may expand, so it is a good idea
to also include \\code{...} in your function signature)."
# jcheng 08/31/2012: User submitted an example of a dynamically calculated
# name not working unless name was eagerly evaluated. Yikes!
force(name)
# If overwriting an output object, suspend the previous copy of it
if (!is.null(private$.outputs[[name]])) {
private$.outputs[[name]]$suspend()
}
if (is.function(func)) {
funcFormals <- formals(func)
# ..stacktraceon matches with the top-level ..stacktraceoff.., because
# the observer we set up below has ..stacktraceon=FALSE
func <- wrapFunctionLabel(func, paste0("output$", name), ..stacktraceon = TRUE)
if (length(funcFormals) != 0) {
orig <- func
func <- function() {
orig(name=name, shinysession=self)
}
}
# Preserve source reference and file information when formatting the
# label for display in the reactive graph
srcref <- attr(label, "srcref")
srcfile <- attr(label, "srcfile")
label <- sprintf('output$%s', name)
attr(label, "srcref") <- srcref
attr(label, "srcfile") <- srcfile
obs <- observe(..stacktraceon = FALSE, {
private$sendMessage(recalculating = list(
name = name, status = 'recalculating'
))
value <- tryCatch(
shinyCallingHandlers(func()),
shiny.custom.error = function(cond) {
if (isTRUE(getOption("show.error.messages"))) printError(cond)
structure(NULL, class = "try-error", condition = cond)
},
shiny.output.cancel = function(cond) {
structure(NULL, class = "cancel-output")
},
shiny.silent.error = function(cond) {
# Don't let shiny.silent.error go through the normal stop
# path of try, because we don't want it to print. But we
# do want to try to return the same looking result so that
# the code below can send the error to the browser.
structure(NULL, class = "try-error", condition = cond)
},
error = function(cond) {
if (isTRUE(getOption("show.error.messages"))) printError(cond)
if (getOption("shiny.sanitize.errors", FALSE)) {
cond <- simpleError(paste("An error has occurred. Check your",
"logs or contact the app author for",
"clarification."))
}
invisible(structure(NULL, class = "try-error", condition = cond))
},
finally = {
private$sendMessage(recalculating = list(
name = name, status = 'recalculated'
))
}
)
if (inherits(value, "cancel-output")) {
return()
}
private$invalidatedOutputErrors$remove(name)
private$invalidatedOutputValues$remove(name)
if (inherits(value, 'try-error')) {
cond <- attr(value, 'condition')
type <- setdiff(class(cond), c('simpleError', 'error', 'condition'))
private$invalidatedOutputErrors$set(
name,
list(message = cond$message,
call = utils::capture.output(print(cond$call)),
type = if (length(type)) type))
}
else
private$invalidatedOutputValues$set(name, value)
}, suspended=private$shouldSuspend(name), label=label)
obs$onInvalidate(function() {
self$showProgress(name)
})
private$.outputs[[name]] <- obs
if (is.null(private$.outputOptions[[name]]))
private$.outputOptions[[name]] <- list()
}
else {
stop(paste("Unexpected", class(func), "output for", name))
}
},
flushOutput = function() {
# ..stacktraceon matches with the top-level ..stacktraceoff..
private$flushCallbacks$invoke(..stacktraceon = TRUE)
# ..stacktraceon matches with the top-level ..stacktraceoff..
on.exit(private$flushedCallbacks$invoke(..stacktraceon = TRUE))
if (length(private$progressKeys) == 0
&& length(private$invalidatedOutputValues) == 0
&& length(private$invalidatedOutputErrors) == 0
&& length(private$inputMessageQueue) == 0) {
return(invisible())
}
private$progressKeys <- character(0)
values <- private$invalidatedOutputValues
private$invalidatedOutputValues <- Map$new()
errors <- private$invalidatedOutputErrors
private$invalidatedOutputErrors <- Map$new()
inputMessages <- private$inputMessageQueue
private$inputMessageQueue <- list()
private$sendMessage(
errors = as.list(errors),
values = as.list(values),
inputMessages = inputMessages
)
},
showProgress = function(id) {
'Send a message to the client that recalculation of the output identified
by \\code{id} is in progress. There is currently no mechanism for
explicitly turning off progress for an output component; instead, all
progress is implicitly turned off when flushOutput is next called.'
# If app is already closed, be sure not to show progress, otherwise we
# will get an error because of the closed websocket
if (self$closed)
return()
if (id %in% private$progressKeys)
return()
private$progressKeys <- c(private$progressKeys, id)
self$sendProgress('binding', list(id = id))
},
sendProgress = function(type, message) {
private$sendMessage(
progress = list(type = type, message = message)
)
},
sendNotification = function(type, message) {
private$sendMessage(
notification = list(type = type, message = message)
)
},
sendModal = function(type, message) {
private$sendMessage(
modal = list(type = type, message = message)
)
},
dispatch = function(msg) {
method <- paste('@', msg$method, sep='')
func <- try(self[[method]], silent = TRUE)
if (inherits(func, 'try-error')) {
private$sendErrorResponse(msg, paste('Unknown method', msg$method))
}
value <- try(do.call(func, as.list(append(msg$args, msg$blobs))),
silent=TRUE)
if (inherits(value, 'try-error')) {
private$sendErrorResponse(msg, conditionMessage(attr(value, 'condition')))
}
else {
private$sendResponse(msg, value)
}
},
sendCustomMessage = function(type, message) {
data <- list()
data[[type]] <- message
private$sendMessage(custom = data)
},
sendInputMessage = function(inputId, message) {
data <- list(id = inputId, message = message)
# Add to input message queue
private$inputMessageQueue[[length(private$inputMessageQueue) + 1]] <- data
},
onFlush = function(flushCallback, once = TRUE) {
if (!isTRUE(once)) {
return(private$flushCallbacks$register(flushCallback))
} else {
dereg <- private$flushCallbacks$register(function() {
dereg()
flushCallback()
})
return(dereg)
}
},
onFlushed = function(flushedCallback, once = TRUE) {
if (!isTRUE(once)) {
return(private$flushedCallbacks$register(flushedCallback))
} else {
dereg <- private$flushedCallbacks$register(function() {
dereg()
flushedCallback()
})
return(dereg)
}
},
reactlog = function(logEntry) {
if (private$showcase)
private$sendMessage(reactlog = logEntry)
},
reload = function() {
private$sendMessage(reload = TRUE)
},
sendInsertUI = function(selector, multiple, where,
content, container) {
private$sendMessage(
`shiny-insert-ui` = list(
selector = selector,
multiple = multiple,
where = where,
content = content,
container = container
)
)
},
sendRemoveUI = function(selector, multiple) {
private$sendMessage(
`shiny-remove-ui` = list(
selector = selector,
multiple = multiple
)
)
},
# Public RPC methods
`@uploadieFinish` = function() {
# Do nothing; just want the side effect of flushReact, output flush, etc.
},
`@uploadInit` = function(fileInfos) {
maxSize <- getOption('shiny.maxRequestSize', 5 * 1024 * 1024)
fileInfos <- lapply(fileInfos, function(fi) {
if (is.null(fi$type))
fi$type <- getContentType(fi$name)
fi
})
sizes <- sapply(fileInfos, function(fi){ fi$size })
if (maxSize > 0 && any(sizes > maxSize)) {
stop("Maximum upload size exceeded")
}
jobId <- private$fileUploadContext$createUploadOperation(fileInfos)
return(list(jobId=jobId,
uploadUrl=paste('session', self$token, 'upload',
paste(jobId, "?w=", workerId(), sep=""),
sep='/')))
},
`@uploadEnd` = function(jobId, inputId) {
fileData <- private$fileUploadContext$getUploadOperation(jobId)$finish()
private$.input$set(inputId, fileData)
invisible()
},
# Provides a mechanism for handling direct HTTP requests that are posted
# to the session (rather than going through the websocket)
handleRequest = function(req) {
# TODO: Turn off caching for the response
subpath <- req$PATH_INFO
matches <- regmatches(subpath,
regexec("^/([a-z]+)/([^?]*)",
subpath,
ignore.case=TRUE))[[1]]
if (length(matches) == 0)
return(httpResponse(400, 'text/html', '<h1>Bad Request</h1>'))
if (matches[2] == 'file') {
savedFile <- self$files$get(URLdecode(matches[3]))
if (is.null(savedFile))
return(httpResponse(404, 'text/html', '<h1>Not Found</h1>'))
return(httpResponse(200, savedFile$contentType, savedFile$data))
}
if (matches[2] == 'upload' && identical(req$REQUEST_METHOD, "POST")) {
job <- private$fileUploadContext$getUploadOperation(matches[3])
if (!is.null(job)) {
fileName <- req$HTTP_SHINY_FILE_NAME
fileType <- req$HTTP_SHINY_FILE_TYPE
fileSize <- req$CONTENT_LENGTH
job$fileBegin()
reqInput <- req$rook.input
while (length(buf <- reqInput$read(2^16)) > 0)
job$fileChunk(buf)
job$fileEnd()
return(httpResponse(200, 'text/plain', 'OK'))
}
}
if (matches[2] == 'uploadie' && identical(req$REQUEST_METHOD, "POST")) {
id <- URLdecode(matches[3])
res <- mime::parse_multipart(req)
private$.input$set(id, res[[id]])
return(httpResponse(200, 'text/plain', 'OK'))
}
if (matches[2] == 'download') {
# A bunch of ugliness here. Filenames can be dynamically generated by
# the user code, so we don't know what they'll be in advance. But the
# most reliable way to use non-ASCII filenames for downloads is to
# put the actual filename in the URL. So we will start with URLs in
# the form:
#
# /session/$TOKEN/download/$NAME
#
# When a request matching that pattern is received, we will calculate
# the filename and see if it's non-ASCII; if so, we'll redirect to
#
# /session/$TOKEN/download/$NAME/$FILENAME
#
# And when that pattern is received, we will actually return the file.
# Note that this means the filename and contents could be determined
# a few moments apart from each other (an HTTP roundtrip basically),
# hopefully that won't be enough to matter for anyone.
dlmatches <- regmatches(matches[3],
regexec("^([^/]+)(/[^/]+)?$",
matches[3]))[[1]]
dlname <- URLdecode(dlmatches[2])
download <- self$downloads$get(dlname)
if (is.null(download))
return(httpResponse(404, 'text/html', '<h1>Not Found</h1>'))
filename <- ifelse(is.function(download$filename),
Context$new(getDefaultReactiveDomain(), '[download]')$run(
download$filename
),
download$filename)
# If the URL does not contain the filename, and the desired filename
# contains non-ASCII characters, then do a redirect with the desired
# name tacked on the end.
if (dlmatches[3] == '' && grepl('[^ -~]', filename)) {
return(httpResponse(302, 'text/html', '<h1>Found</h1>', c(
'Location' = sprintf('%s/%s',
URLencode(dlname, TRUE),
URLencode(filename, TRUE)),
'Cache-Control' = 'no-cache')))
}
# Make temp file with the same extension as the user-visible filename.
# If the extension is not used, some functions such as pdf() and zip()
# may append the extension they expect, meaning the data we want will
# be written to a file other than our temp file (e.g. file1231.zip
# instead of file1231.zip).
ext <- tools::file_ext(filename)
if (nzchar(ext))
ext <- paste(".", ext, sep = "")
tmpdata <- tempfile(fileext = ext)
# ..stacktraceon matches with the top-level ..stacktraceoff..
result <- try(shinyCallingHandlers(Context$new(getDefaultReactiveDomain(), '[download]')$run(
function() { ..stacktraceon..(download$func(tmpdata)) }
)), silent = TRUE)
if (inherits(result, 'try-error')) {
unlink(tmpdata)
stop(attr(result, "condition", exact = TRUE))
}
return(httpResponse(
200,
download$contentType %OR% getContentType(filename),
# owned=TRUE means tmpdata will be deleted after response completes
list(file=tmpdata, owned=TRUE),
c(
'Content-Disposition' = ifelse(
dlmatches[3] == '',
'attachment; filename="' %.%
gsub('(["\\\\])', '\\\\\\1', filename) %.% # yes, that many \'s
'"',
'attachment'
),
'Cache-Control'='no-cache')))
}
if (matches[2] == 'dataobj') {
# /session/$TOKEN/dataobj/$NAME
dlmatches <- regmatches(matches[3],
regexec("^([^/]+)(/[^/]+)?$",
matches[3]))[[1]]
dlname <- URLdecode(dlmatches[2])
download <- self$downloads$get(dlname)
return(download$filter(download$data, req))
}
return(httpResponse(404, 'text/html', '<h1>Not Found</h1>'))
},
saveFileUrl = function(name, data, contentType, extra=list()) {
"Creates an entry in the file map for the data, and returns a URL pointing
to the file."
self$files$set(name, list(data=data, contentType=contentType))
return(sprintf('session/%s/file/%s?w=%s&r=%s',
URLencode(self$token, TRUE),
URLencode(name, TRUE),
workerId(),
createUniqueId(8)))
},
# Send a file to the client
fileUrl = function(name, file, contentType='application/octet-stream') {
"Return a URL for a file to be sent to the client. If allowDataUriScheme
is TRUE, then the file will be base64 encoded and embedded in the URL.
Otherwise, a URL pointing to the file will be returned."
bytes <- file.info(file)$size
if (is.na(bytes))
return(NULL)
fileData <- readBin(file, 'raw', n=bytes)
if (isTRUE(private$.clientData$.values$allowDataUriScheme)) {
b64 <- rawToBase64(fileData)
return(paste('data:', contentType, ';base64,', b64, sep=''))
} else {
return(self$saveFileUrl(name, fileData, contentType))
}
},
registerDownload = function(name, filename, contentType, func) {
self$downloads$set(name, list(filename = filename,
contentType = contentType,
func = func))
return(sprintf('session/%s/download/%s?w=%s',
URLencode(self$token, TRUE),
URLencode(name, TRUE),
workerId()))
},
# register a data object on the server side (for datatable or selectize, etc)
registerDataObj = function(name, data, filterFunc) {
# abusing downloads at the moment
self$downloads$set(name, list(data = data, filter = filterFunc))
return(sprintf('session/%s/dataobj/%s?w=%s',
URLencode(self$token, TRUE),
URLencode(name, TRUE),
workerId()))
},
# This function suspends observers for hidden outputs and resumes observers
# for un-hidden outputs.
manageHiddenOutputs = function() {
# Find hidden state for each output, and suspend/resume accordingly
for (outputName in names(private$.outputs)) {
if (private$shouldSuspend(outputName)) {
private$.outputs[[outputName]]$suspend()
} else {
private$.outputs[[outputName]]$resume()
}
}
},
# Set the normal and client data input variables
manageInputs = function(data) {
private$inputReceivedCallbacks$invoke(data)
data_names <- names(data)
# Separate normal input variables from client data input variables
clientdata_idx <- grepl("^.clientdata_", data_names)
# Set normal (non-clientData) input values
private$.input$mset(data[data_names[!clientdata_idx]])
# Strip off .clientdata_ from clientdata input names, and set values
input_clientdata <- data[data_names[clientdata_idx]]
names(input_clientdata) <- sub("^.clientdata_", "",
names(input_clientdata))
private$.clientData$mset(input_clientdata)
},
outputOptions = function(name, ...) {
# If no name supplied, return the list of options for all outputs
if (is.null(name))
return(private$.outputOptions)
if (! name %in% names(private$.outputs))
stop(name, " is not in list of output objects")
opts <- list(...)
# If no options are set, return the options for the specified output
if (length(opts) == 0)
return(private$.outputOptions[[name]])
# Set the appropriate option
validOpts <- c("suspendWhenHidden", "priority")
for (optname in names(opts)) {
if (! optname %in% validOpts)
stop(optname, " is not a valid option")
private$.outputOptions[[name]][[optname]] <- opts[[optname]]
}
# If any changes to suspendWhenHidden, need to re-run manageHiddenOutputs
if ("suspendWhenHidden" %in% names(opts)) {
self$manageHiddenOutputs()
}
if ("priority" %in% names(opts)) {
private$.outputs[[name]]$setPriority(opts[['priority']])
}
invisible()
},
incrementBusyCount = function() {
if (private$busyCount == 0L) {
private$sendMessage(busy = "busy")
}
private$busyCount <- private$busyCount + 1L
},
decrementBusyCount = function() {
private$busyCount <- private$busyCount - 1L
if (private$busyCount == 0L) {
private$sendMessage(busy = "idle")
}
}
),
active = list(
session = function() {
shinyDeprecated(
msg = paste("Attempted to access deprecated shinysession$session object.",
"Please just access the shinysession object directly."),
version = "0.11.1"
)
self
}
)
)
.createOutputWriter <- function(shinysession, ns = identity) {
structure(list(impl=shinysession, ns=ns), class='shinyoutput')
}
#' @export
`$<-.shinyoutput` <- function(x, name, value) {
name <- .subset2(x, 'ns')(name)
label <- deparse(substitute(value))
if (length(substitute(value)) > 1) {
# value is an object consisting of a call and its arguments. Here we want
# to find the source references for the first argument (if there are
# arguments), which generally corresponds to the reactive expression--
# e.g. in renderTable({ x }), { x } is the expression to trace.
attr(label, "srcref") <- srcrefFromShinyCall(substitute(value)[[2]])
srcref <- attr(substitute(value)[[2]], "srcref")
if (length(srcref) > 0)
attr(label, "srcfile") <- srcFileOfRef(srcref[[1]])
}
.subset2(x, 'impl')$defineOutput(name, value, label)
return(invisible(x))
}
#' @export
`[[<-.shinyoutput` <- `$<-.shinyoutput`
#' @export
`$.shinyoutput` <- function(x, name) {
stop("Reading objects from shinyoutput object not allowed.")
}
#' @export
`[[.shinyoutput` <- `$.shinyoutput`
#' @export
`[.shinyoutput` <- function(values, name) {
stop("Single-bracket indexing of shinyoutput object is not allowed.")
}
#' @export
`[<-.shinyoutput` <- function(values, name, value) {
stop("Single-bracket indexing of shinyoutput object is not allowed.")
}
#' Set options for an output object.
#'
#' These are the available options for an output object:
#' \itemize{
#' \item suspendWhenHidden. When \code{TRUE} (the default), the output object
#' will be suspended (not execute) when it is hidden on the web page. When
#' \code{FALSE}, the output object will not suspend when hidden, and if it
#' was already hidden and suspended, then it will resume immediately.
#' \item priority. The priority level of the output object. Queued outputs
#' with higher priority values will execute before those with lower values.
#' }
#'
#' @examples
#' \dontrun{
#' # Get the list of options for all observers within output
#' outputOptions(output)
#'
#' # Disable suspend for output$myplot
#' outputOptions(output, "myplot", suspendWhenHidden = FALSE)
#'
#' # Change priority for output$myplot
#' outputOptions(output, "myplot", priority = 10)
#'
#' # Get the list of options for output$myplot
#' outputOptions(output, "myplot")
#' }
#'
#' @param x A shinyoutput object (typically \code{output}).
#' @param name The name of an output observer in the shinyoutput object.
#' @param ... Options to set for the output observer.
#' @export
outputOptions <- function(x, name, ...) {
if (!inherits(x, "shinyoutput"))
stop("x must be a shinyoutput object.")
name <- .subset2(x, 'ns')(name)
.subset2(x, 'impl')$outputOptions(name, ...)
}
ymd526442121/Rproject_shiny documentation built on May 4, 2019, 5:31 p.m.
R Package Documentation
Browse R Packages
We want your feedback!
Note that we can't provide technical support on individual packages. You should contact the package authors for that.
Defines functions createUniqueId toJSON NS .createOutputWriter `$<-.shinyoutput` `$.shinyoutput` `[.shinyoutput` `[<-.shinyoutput` outputOptions
Documented in NS outputOptions
#' @include utils.R stack.R
NULL
#' Web Application Framework for R
#'
#' Shiny makes it incredibly easy to build interactive web applications with R.
#' Automatic "reactive" binding between inputs and outputs and extensive
#' pre-built widgets make it possible to build beautiful, responsive, and
#' powerful applications with minimal effort.
#'
#' The Shiny tutorial at \url{http://shiny.rstudio.com/tutorial/} explains
#' the framework in depth, walks you through building a simple application, and
#' includes extensive annotated examples.
#'
#' @seealso \link{shiny-options} for documentation about global options.
#'
#' @name shiny-package
#' @aliases shiny
#' @docType package
#' @import htmltools httpuv xtable digest R6 mime
NULL
# It's necessary to Depend on methods so Rscript doesn't fail. It's necessary
# to import(methods) in NAMESPACE so R CMD check doesn't complain. This
# approach isn't foolproof because Rscript -e pkgname::func() doesn't actually
# cause methods to be attached, but it's not a problem for shiny::runApp()
# since we call require(shiny) as part of loading the app.
#' @import methods
NULL
#' Global options for Shiny
#'
#' There are a number of global options that affect Shiny's behavior. These can
#' be set with (for example) \code{options(shiny.trace=TRUE)}.
#'
#' \describe{
#' \item{shiny.launch.browser}{A boolean which controls the default behavior
#' when an app is run. See \code{\link{runApp}} for more information.}
#' \item{shiny.port}{A port number that Shiny will listen on. See
#' \code{\link{runApp}} for more information.}
#' \item{shiny.trace}{If \code{TRUE}, all of the messages sent between the R
#' server and the web browser client will be printed on the console. This
#' is useful for debugging.}
#' \item{shiny.autoreload}{If \code{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:
#' \code{option(shiny.autoreload.pattern = glob2rx("ui.R"))}
#'
#' The default polling interval is 500 milliseconds. You can change this
#' by setting e.g. \code{option(shiny.autoreload.interval = 2000)} (every
#' two seconds).}
#' \item{shiny.reactlog}{If \code{TRUE}, enable logging of reactive events,
#' which can be viewed later with the \code{\link{showReactLog}} function.
#' This incurs a substantial performance penalty and should not be used in
#' production.}
#' \item{shiny.usecairo}{This is used to disable graphical rendering by the
#' Cairo package, if it is installed. See \code{\link{plotPNG}} for more
#' information.}
#' \item{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.}
#' \item{shiny.suppressMissingContextError}{Normally, invoking a reactive
#' outside of a reactive context (or \code{\link{isolate}()}) results in
#' an error. If this is \code{TRUE}, don't error in these cases. This
#' should only be used for debugging or demonstrations of reactivity at the
#' console.}
#' \item{shiny.host}{The IP address that Shiny should listen on. See
#' \code{\link{runApp}} for more information.}
#' \item{shiny.json.digits}{The number of digits to use when converting
#' numbers to JSON format to send to the client web browser.}
#' \item{shiny.minified}{If this is \code{TRUE} or unset (the default), then
#' Shiny will use minified JavaScript (\code{shiny.min.js}). If
#' \code{FALSE}, then Shiny will use the un-minified JavaScript
#' (\code{shiny.js}); this can be useful during development.}
#' \item{shiny.error}{This can be a function which is called when an error
#' occurs. For example, \code{options(shiny.error=recover)} will result a
#' the debugger prompt when an error occurs.}
#' \item{shiny.table.class}{CSS class names to use for tables.}
#' \item{shiny.deprecation.messages}{This controls whether messages for
#' deprecated functions in Shiny will be printed. See
#' \code{\link{shinyDeprecated}} for more information.}
#' \item{shiny.fullstacktrace}{Controls whether "pretty" or full stack traces
#' are dumped to the console when errors occur during Shiny app execution.
#' The default is \code{FALSE} (pretty stack traces).}
#' \item{shiny.stacktraceoffset}{If \code{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.}
#' \item{shiny.sanitize.errors}{If \code{TRUE}, then normal errors (i.e.
#' errors not wrapped in \code{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 \code{FALSE} (unsanitized
#' errors).If you want to sanitize errors in general, but you DO want a
#' particular error \code{e} to get displayed to the user, then set this option
#' to \code{TRUE} and use \code{stop(safeError(e))} for errors you want the
#' user to see.}
#' }
#' @name shiny-options
NULL
createUniqueId <- function(bytes, prefix = "", suffix = "") {
withPrivateSeed({
paste(
prefix,
paste(
format(as.hexmode(sample(256, bytes, replace = TRUE)-1), width=2),
collapse = ""),
suffix,
sep = ""
)
})
}
toJSON <- function(x, ..., dataframe = "columns", null = "null", na = "null",
auto_unbox = TRUE, digits = getOption("shiny.json.digits", 16),
use_signif = TRUE, force = TRUE, POSIXt = "ISO8601", UTC = TRUE,
rownames = FALSE, keep_vec_names = TRUE) {
# I(x) is so that length-1 atomic vectors get put in [].
jsonlite::toJSON(I(x), dataframe = dataframe, null = null, na = na,
auto_unbox = auto_unbox, digits = digits, use_signif = use_signif,
force = force, POSIXt = POSIXt, UTC = UTC, rownames = rownames,
keep_vec_names = keep_vec_names, json_verbatim = TRUE, ...)
}
# Call the workerId func with no args to get the worker id, and with an arg to
# set it.
#
# A worker ID is an opaque string that is passed in by the caller. The ID is
# added as a URL parameter (?w=<worker_id>) to any URLs that need to refer back
# to the app. This can be used as a hint for load balancers to direct requests
# to this particular process. Since the worker refers to a process, it's
# inherently global, and should never need to change.
workerId <- local({
.workerId <- NULL
function(value) {
if (missing(value)) {
.workerId
} else {
if (!is.null(.workerId)) {
if (!identical(value, .workerId)) {
warning("Ignoring workerId value--",
"it's already been set to a different value")
}
} else {
.workerId <<- value
}
}
}
})
#' Session object
#'
#' Shiny server functions can optionally include \code{session} as a parameter
#' (e.g. \code{function(input, output, session)}). The session object is an
#' environment that can be used to access information and functionality
#' relating to the session. The following list describes the items available
#' in the environment; they can be accessed using the \code{$} operator (for
#' example, \code{session$clientData$url_search}).
#'
#' @return
#' \item{clientData}{
#' A \code{\link{reactiveValues}} object that contains information about the client.
#' \itemize{
#' \item{\code{allowDataUriScheme} is a logical value that indicates whether
#' the browser is able to handle URIs that use the \code{data:} scheme.
#' }
#' \item{\code{pixelratio} reports the "device pixel ratio" from the web browser,
#' or 1 if none is reported. The value is 2 for Apple Retina displays.
#' }
#' \item{\code{singletons} - for internal use}
#' \item{\code{url_protocol}, \code{url_hostname}, \code{url_port},
#' \code{url_pathname}, \code{url_search}, and \code{url_hash_initial}
#' can be used to get the components of the URL that was requested by the
#' browser to load the Shiny app page. These values are from the
#' browser's perspective, so neither HTTP proxies nor Shiny Server will
#' affect these values. The \code{url_search} value may be used with
#' \code{\link{parseQueryString}} to access query string parameters.
#' }
#' }
#' \code{clientData} also contains information about each output.
#' \code{output_\var{outputId}_width} and \code{output_\var{outputId}_height}
#' give the dimensions (using \code{offsetWidth} and \code{offsetHeight}) of
#' the DOM element that is bound to \code{\var{outputId}}, and
#' \code{output_\var{outputId}_hidden} is a logical that indicates whether
#' the element is hidden. These values may be \code{NULL} if the output is
#' not bound.
#' }
#' \item{input}{
#' The session's \code{input} object (the same as is passed into the Shiny
#' server function as an argument).
#' }
#' \item{isClosed()}{A function that returns \code{TRUE} if the client has
#' disconnected.
#' }
#' \item{onEnded(callback)}{
#' Synonym for \code{onSessionEnded}.
#' }
#' \item{onFlush(func, once=TRUE)}{
#' Registers a function to be called before the next time (if \code{once=TRUE})
#' or every time (if \code{once=FALSE}) Shiny flushes the reactive system.
#' Returns a function that can be called with no arguments to cancel the
#' registration.
#' }
#' \item{onFlushed(func, once=TRUE)}{
#' Registers a function to be called after the next time (if \code{once=TRUE})
#' or every time (if \code{once=FALSE}) Shiny flushes the reactive system.
#' Returns a function that can be called with no arguments to cancel the
#' registration.
#' }
#' \item{onSessionEnded(callback)}{
#' Registers a function to be called after the client has disconnected.
#' Returns a function that can be called with no arguments to cancel the
#' registration.
#' }
#' \item{output}{
#' The session's \code{output} object (the same as is passed into the Shiny
#' server function as an argument).
#' }
#' \item{reactlog}{
#' For internal use.
#' }
#' \item{registerDataObj(name, data, filterFunc)}{
#' Publishes any R object as a URL endpoint that is unique to this session.
#' \code{name} must be a single element character vector; it will be used
#' to form part of the URL. \code{filterFunc} must be a function that takes
#' two arguments: \code{data} (the value that was passed into
#' \code{registerDataObj}) and \code{req} (an environment that implements
#' the Rook specification for HTTP requests). \code{filterFunc} will be
#' called with these values whenever an HTTP request is made to the URL
#' endpoint. The return value of \code{filterFunc} should be a Rook-style
#' response.
#' }
#' \item{reload()}{
#' The equivalent of hitting the browser's Reload button. Only works if the
#' session is actually connected.
#' }
#' \item{request}{
#' An environment that implements the Rook specification for HTTP requests.
#' This is the request that was used to initiate the websocket connection
#' (as opposed to the request that downloaded the web page for the app).
#' }
#' \item{allowReconnect(value)}{
#' If \code{value} is \code{TRUE} and run in a hosting environment (Shiny
#' Server or Connect) with reconnections enabled, then when the session ends
#' due to the network connection closing, the client will attempt to
#' reconnect to the server. If a reconnection is successful, the browser will
#' send all the current input values to the new session on the server, and
#' the server will recalculate any outputs and send them back to the client.
#' If \code{value} is \code{FALSE}, reconnections will be disabled (this is
#' the default state). If \code{"force"}, then the client browser will always
#' attempt to reconnect. The only reason to use \code{"force"} is for testing
#' on a local connection (without Shiny Server or Connect).
#' }
#' \item{sendCustomMessage(type, message)}{
#' Sends a custom message to the web page. \code{type} must be a
#' single-element character vector giving the type of message, while
#' \code{message} can be any jsonlite-encodable value. Custom messages
#' have no meaning to Shiny itself; they are used soley to convey information
#' to custom JavaScript logic in the browser. You can do this by adding
#' JavaScript code to the browser that calls
#' \code{Shiny.addCustomMessageHandler(type, function(message){...})}
#' as the page loads; the function you provide to
#' \code{addCustomMessageHandler} will be invoked each time
#' \code{sendCustomMessage} is called on the server.
#' }
#' \item{sendInputMessage(inputId, message)}{
#' Sends a message to an input on the session's client web page; if the input
#' is present and bound on the page at the time the message is received, then
#' the input binding object's \code{receiveMessage(el, message)} method will
#' be called. \code{sendInputMessage} should generally not be called directly
#' from Shiny apps, but through friendlier wrapper functions like
#' \code{\link{updateTextInput}}.
#' }
#' \item{ns(id)}{
#' Server-side version of \code{ns <- \link{NS}(id)}. If bare IDs need to be
#' explicitly namespaced for the current module, \code{session$ns("name")}
#' will return the fully-qualified ID.
#' }
#'
#' @name session
NULL
#' Namespaced IDs for inputs/outputs
#'
#' The \code{NS} function creates namespaced IDs out of bare IDs, by joining
#' them using \code{ns.sep} as the delimiter. It is intended for use in Shiny
#' modules. See \url{http://shiny.rstudio.com/articles/modules.html}.
#'
#' Shiny applications use IDs to identify inputs and outputs. These IDs must be
#' unique within an application, as accidentally using the same input/output ID
#' more than once will result in unexpected behavior. The traditional solution
#' for preventing name collisions is \emph{namespaces}; a namespace is to an ID
#' as a directory is to a file. Use the \code{NS} function to turn a bare ID
#' into a namespaced one, by combining them with \code{ns.sep} in between.
#'
#' @param namespace The character vector to use for the namespace. This can have
#' any length, though a single element is most common. Length 0 will cause the
#' \code{id} to be returned without a namespace, and length 2 will be
#' interpreted as multiple namespaces, in increasing order of specificity
#' (i.e. starting with the top-level namespace).
#' @param id The id string to be namespaced (optional).
#' @return If \code{id} is missing, returns a function that expects an id string
#' as its only argument and returns that id with the namespace prepended.
#' @seealso \url{http://shiny.rstudio.com/articles/modules.html}
#'
#' @export
NS <- function(namespace, id = NULL) {
if (missing(id)) {
function(id) {
paste(c(namespace, id), collapse = ns.sep)
}
} else {
paste(c(namespace, id), collapse = ns.sep)
}
}
#' @rdname NS
#' @export
ns.sep <- "-"
#' @include utils.R
ShinySession <- R6Class(
'ShinySession',
private = list(
# There are some private items with a leading "."; except for the dot, these
# items share a name with a public item.
websocket = 'ANY',
invalidatedOutputValues = 'Map',
invalidatedOutputErrors = 'Map',
inputMessageQueue = list(), # A list of inputMessages to send when flushed
.outputs = list(), # Keeps track of all the output observer objects
.outputOptions = list(), # Options for each of the output observer objects
progressKeys = 'character',
showcase = 'ANY',
fileUploadContext = 'FileUploadContext',
.input = 'ANY', # Internal ReactiveValues object for normal input sent from client
.clientData = 'ANY', # Internal ReactiveValues object for other data sent from the client
busyCount = 0L, # Number of observer callbacks that are pending. When 0, we are idle
closedCallbacks = 'Callbacks',
flushCallbacks = 'Callbacks',
flushedCallbacks = 'Callbacks',
inputReceivedCallbacks = 'Callbacks',
sendResponse = function(requestMsg, value) {
if (is.null(requestMsg$tag)) {
warning("Tried to send response for untagged message; method: ",
requestMsg$method)
return()
}
private$sendMessage(
response = list(tag = requestMsg$tag, value = value)
)
},
sendErrorResponse = function(requestMsg, error) {
if (is.null(requestMsg$tag))
return()
private$sendMessage(
response = list(tag = requestMsg$tag, error = error)
)
},
write = function(json) {
if (self$closed){
return()
}
if (isTRUE(getOption('shiny.trace')))
message('SEND ',
gsub('(?m)base64,[a-zA-Z0-9+/=]+','[base64 data]',json,perl=TRUE))
private$websocket$send(json)
},
sendMessage = function(...) {
# This function is a wrapper for $write
msg <- list(...)
if (anyUnnamed(msg)) {
stop("All arguments to sendMessage must be named.")
}
private$write(toJSON(msg))
},
getOutputOption = function(outputName, propertyName, defaultValue) {
opts <- private$.outputOptions[[outputName]]
if (is.null(opts))
return(defaultValue)
result <- opts[[propertyName]]
if (is.null(result))
return(defaultValue)
return(result)
},
shouldSuspend = function(name) {
# Find corresponding hidden state clientData variable, with the format
# "output_foo_hidden". (It comes from .clientdata_output_foo_hidden
# on the JS side)
# Some tricky stuff: instead of accessing names using input$names(),
# get the names directly via input$.values, to avoid triggering reactivity.
# Need to handle cases where the output object isn't actually used
# in the web page; in these cases, there's no output_foo_hidden flag,
# and hidden should be TRUE. In other words, NULL and TRUE should map to
# TRUE, FALSE should map to FALSE.
hidden <- private$.clientData$.values[[paste("output_", name, "_hidden",
sep="")]]
if (is.null(hidden)) hidden <- TRUE
return(hidden && private$getOutputOption(name, 'suspendWhenHidden', TRUE))
},
registerSessionEndCallbacks = function() {
# This is to be called from the initialization. It registers functions
# that are called when a session ends.
# Clear file upload directories, if present
self$onSessionEnded(private$fileUploadContext$rmUploadDirs)
}
),
public = list(
progressStack = 'Stack', # Stack of progress objects
input = 'reactivevalues', # Externally-usable S3 wrapper object for .input
output = 'ANY', # Externally-usable S3 wrapper object for .outputs
clientData = 'reactivevalues', # Externally-usable S3 wrapper object for .clientData
token = 'character', # Used to identify this instance in URLs
files = 'Map', # For keeping track of files sent to client
downloads = 'Map',
closed = logical(0),
request = 'ANY', # Websocket request object
singletons = character(0), # Tracks singleton HTML fragments sent to the page
user = NULL,
groups = NULL,
initialize = function(websocket) {
private$websocket <- websocket
self$closed <- FALSE
# TODO: Put file upload context in user/app-specific dir if possible
private$invalidatedOutputValues <- Map$new()
private$invalidatedOutputErrors <- Map$new()
private$fileUploadContext <- FileUploadContext$new()
private$closedCallbacks <- Callbacks$new()
private$flushCallbacks <- Callbacks$new()
private$flushedCallbacks <- Callbacks$new()
private$inputReceivedCallbacks <- Callbacks$new()
private$.input <- ReactiveValues$new()
private$.clientData <- ReactiveValues$new()
self$progressStack <- Stack$new()
self$files <- Map$new()
self$downloads <- Map$new()
self$input <- .createReactiveValues(private$.input, readonly=TRUE)
.setLabel(self$input, 'input')
self$clientData <- .createReactiveValues(private$.clientData, readonly=TRUE)
.setLabel(self$clientData, 'clientData')
self$output <- .createOutputWriter(self)
self$token <- createUniqueId(16)
private$.outputs <- list()
private$.outputOptions <- list()
private$registerSessionEndCallbacks()
if (!is.null(websocket$request$HTTP_SHINY_SERVER_CREDENTIALS)) {
try({
creds <- jsonlite::fromJSON(websocket$request$HTTP_SHINY_SERVER_CREDENTIALS)
self$user <- creds$user
self$groups <- creds$groups
}, silent=FALSE)
}
# session$request should throw an error if httpuv doesn't have
# websocket$request, but don't throw it until a caller actually
# tries to access session$request
delayedAssign('request', websocket$request, assign.env = self)
private$sendMessage(
config = list(
workerId = workerId(),
sessionId = self$token
)
)
},
makeScope = function(namespace) {
ns <- NS(namespace)
createSessionProxy(self,
input = .createReactiveValues(private$.input, readonly = TRUE, ns = ns),
output = .createOutputWriter(self, ns = ns),
sendInputMessage = function(inputId, message) {
.subset2(self, "sendInputMessage")(ns(inputId), message)
},
registerDataObj = function(name, data, filterFunc) {
.subset2(self, "registerDataObj")(ns(name), data, filterFunc)
},
ns = ns,
makeScope = function(namespace) {
self$makeScope(ns(namespace))
}
)
},
ns = function(id) {
NS(NULL, id)
},
onSessionEnded = function(sessionEndedCallback) {
"Registers the given callback to be invoked when the session is closed
(i.e. the connection to the client has been severed). The return value
is a function which unregisters the callback. If multiple callbacks are
registered, the order in which they are invoked is not guaranteed."
return(private$closedCallbacks$register(sessionEndedCallback))
},
onEnded = function(endedCallback) {
"Synonym for onSessionEnded"
return(self$onSessionEnded(endedCallback))
},
onInputReceived = function(callback) {
"Registers the given callback to be invoked when the session receives
new data from the client."
return(private$inputReceivedCallbacks$register(callback))
},
unhandledError = function(e) {
self$close()
},
close = function() {
if (!self$closed) {
private$websocket$close()
}
},
wsClosed = function() {
self$closed <- TRUE
for (output in private$.outputs) {
output$suspend()
}
# ..stacktraceon matches with the top-level ..stacktraceoff..
private$closedCallbacks$invoke(onError = printError, ..stacktraceon = TRUE)
flushReact()
lapply(appsByToken$values(), function(shinysession) {
shinysession$flushOutput()
NULL
})
},
isClosed = function() {
return(self$closed)
},
isEnded = function() {
return(self$isClosed())
},
setShowcase = function(value) {
private$showcase <- !is.null(value) && as.logical(value)
},
allowReconnect = function(value) {
if (!(identical(value, TRUE) || identical(value, FALSE) || identical(value, "force"))) {
stop('value must be TRUE, FALSE, or "force"')
}
private$write(toJSON(list(allowReconnect = value)))
},
defineOutput = function(name, func, label) {
"Binds an output generating function to this name. The function can either
take no parameters, or have named parameters for \\code{name} and
\\code{shinysession} (in the future this list may expand, so it is a good idea
to also include \\code{...} in your function signature)."
# jcheng 08/31/2012: User submitted an example of a dynamically calculated
# name not working unless name was eagerly evaluated. Yikes!
force(name)
# If overwriting an output object, suspend the previous copy of it
if (!is.null(private$.outputs[[name]])) {
private$.outputs[[name]]$suspend()
}
if (is.function(func)) {
funcFormals <- formals(func)
# ..stacktraceon matches with the top-level ..stacktraceoff.., because
# the observer we set up below has ..stacktraceon=FALSE
func <- wrapFunctionLabel(func, paste0("output$", name), ..stacktraceon = TRUE)
if (length(funcFormals) != 0) {
orig <- func
func <- function() {
orig(name=name, shinysession=self)
}
}
# Preserve source reference and file information when formatting the
# label for display in the reactive graph
srcref <- attr(label, "srcref")
srcfile <- attr(label, "srcfile")
label <- sprintf('output$%s', name)
attr(label, "srcref") <- srcref
attr(label, "srcfile") <- srcfile
obs <- observe(..stacktraceon = FALSE, {
private$sendMessage(recalculating = list(
name = name, status = 'recalculating'
))
value <- tryCatch(
shinyCallingHandlers(func()),
shiny.custom.error = function(cond) {
if (isTRUE(getOption("show.error.messages"))) printError(cond)
structure(NULL, class = "try-error", condition = cond)
},
shiny.output.cancel = function(cond) {
structure(NULL, class = "cancel-output")
},
shiny.silent.error = function(cond) {
# Don't let shiny.silent.error go through the normal stop
# path of try, because we don't want it to print. But we
# do want to try to return the same looking result so that
# the code below can send the error to the browser.
structure(NULL, class = "try-error", condition = cond)
},
error = function(cond) {
if (isTRUE(getOption("show.error.messages"))) printError(cond)
if (getOption("shiny.sanitize.errors", FALSE)) {
cond <- simpleError(paste("An error has occurred. Check your",
"logs or contact the app author for",
"clarification."))
}
invisible(structure(NULL, class = "try-error", condition = cond))
},
finally = {
private$sendMessage(recalculating = list(
name = name, status = 'recalculated'
))
}
)
if (inherits(value, "cancel-output")) {
return()
}
private$invalidatedOutputErrors$remove(name)
private$invalidatedOutputValues$remove(name)
if (inherits(value, 'try-error')) {
cond <- attr(value, 'condition')
type <- setdiff(class(cond), c('simpleError', 'error', 'condition'))
private$invalidatedOutputErrors$set(
name,
list(message = cond$message,
call = utils::capture.output(print(cond$call)),
type = if (length(type)) type))
}
else
private$invalidatedOutputValues$set(name, value)
}, suspended=private$shouldSuspend(name), label=label)
obs$onInvalidate(function() {
self$showProgress(name)
})
private$.outputs[[name]] <- obs
if (is.null(private$.outputOptions[[name]]))
private$.outputOptions[[name]] <- list()
}
else {
stop(paste("Unexpected", class(func), "output for", name))
}
},
flushOutput = function() {
# ..stacktraceon matches with the top-level ..stacktraceoff..
private$flushCallbacks$invoke(..stacktraceon = TRUE)
# ..stacktraceon matches with the top-level ..stacktraceoff..
on.exit(private$flushedCallbacks$invoke(..stacktraceon = TRUE))
if (length(private$progressKeys) == 0
&& length(private$invalidatedOutputValues) == 0
&& length(private$invalidatedOutputErrors) == 0
&& length(private$inputMessageQueue) == 0) {
return(invisible())
}
private$progressKeys <- character(0)
values <- private$invalidatedOutputValues
private$invalidatedOutputValues <- Map$new()
errors <- private$invalidatedOutputErrors
private$invalidatedOutputErrors <- Map$new()
inputMessages <- private$inputMessageQueue
private$inputMessageQueue <- list()
private$sendMessage(
errors = as.list(errors),
values = as.list(values),
inputMessages = inputMessages
)
},
showProgress = function(id) {
'Send a message to the client that recalculation of the output identified
by \\code{id} is in progress. There is currently no mechanism for
explicitly turning off progress for an output component; instead, all
progress is implicitly turned off when flushOutput is next called.'
# If app is already closed, be sure not to show progress, otherwise we
# will get an error because of the closed websocket
if (self$closed)
return()
if (id %in% private$progressKeys)
return()
private$progressKeys <- c(private$progressKeys, id)
self$sendProgress('binding', list(id = id))
},
sendProgress = function(type, message) {
private$sendMessage(
progress = list(type = type, message = message)
)
},
sendNotification = function(type, message) {
private$sendMessage(
notification = list(type = type, message = message)
)
},
sendModal = function(type, message) {
private$sendMessage(
modal = list(type = type, message = message)
)
},
dispatch = function(msg) {
method <- paste('@', msg$method, sep='')
func <- try(self[[method]], silent = TRUE)
if (inherits(func, 'try-error')) {
private$sendErrorResponse(msg, paste('Unknown method', msg$method))
}
value <- try(do.call(func, as.list(append(msg$args, msg$blobs))),
silent=TRUE)
if (inherits(value, 'try-error')) {
private$sendErrorResponse(msg, conditionMessage(attr(value, 'condition')))
}
else {
private$sendResponse(msg, value)
}
},
sendCustomMessage = function(type, message) {
data <- list()
data[[type]] <- message
private$sendMessage(custom = data)
},
sendInputMessage = function(inputId, message) {
data <- list(id = inputId, message = message)
# Add to input message queue
private$inputMessageQueue[[length(private$inputMessageQueue) + 1]] <- data
},
onFlush = function(flushCallback, once = TRUE) {
if (!isTRUE(once)) {
return(private$flushCallbacks$register(flushCallback))
} else {
dereg <- private$flushCallbacks$register(function() {
dereg()
flushCallback()
})
return(dereg)
}
},
onFlushed = function(flushedCallback, once = TRUE) {
if (!isTRUE(once)) {
return(private$flushedCallbacks$register(flushedCallback))
} else {
dereg <- private$flushedCallbacks$register(function() {
dereg()
flushedCallback()
})
return(dereg)
}
},
reactlog = function(logEntry) {
if (private$showcase)
private$sendMessage(reactlog = logEntry)
},
reload = function() {
private$sendMessage(reload = TRUE)
},
sendInsertUI = function(selector, multiple, where,
content, container) {
private$sendMessage(
`shiny-insert-ui` = list(
selector = selector,
multiple = multiple,
where = where,
content = content,
container = container
)
)
},
sendRemoveUI = function(selector, multiple) {
private$sendMessage(
`shiny-remove-ui` = list(
selector = selector,
multiple = multiple
)
)
},
# Public RPC methods
`@uploadieFinish` = function() {
# Do nothing; just want the side effect of flushReact, output flush, etc.
},
`@uploadInit` = function(fileInfos) {
maxSize <- getOption('shiny.maxRequestSize', 5 * 1024 * 1024)
fileInfos <- lapply(fileInfos, function(fi) {
if (is.null(fi$type))
fi$type <- getContentType(fi$name)
fi
})
sizes <- sapply(fileInfos, function(fi){ fi$size })
if (maxSize > 0 && any(sizes > maxSize)) {
stop("Maximum upload size exceeded")
}
jobId <- private$fileUploadContext$createUploadOperation(fileInfos)
return(list(jobId=jobId,
uploadUrl=paste('session', self$token, 'upload',
paste(jobId, "?w=", workerId(), sep=""),
sep='/')))
},
`@uploadEnd` = function(jobId, inputId) {
fileData <- private$fileUploadContext$getUploadOperation(jobId)$finish()
private$.input$set(inputId, fileData)
invisible()
},
# Provides a mechanism for handling direct HTTP requests that are posted
# to the session (rather than going through the websocket)
handleRequest = function(req) {
# TODO: Turn off caching for the response
subpath <- req$PATH_INFO
matches <- regmatches(subpath,
regexec("^/([a-z]+)/([^?]*)",
subpath,
ignore.case=TRUE))[[1]]
if (length(matches) == 0)
return(httpResponse(400, 'text/html', '<h1>Bad Request</h1>'))
if (matches[2] == 'file') {
savedFile <- self$files$get(URLdecode(matches[3]))
if (is.null(savedFile))
return(httpResponse(404, 'text/html', '<h1>Not Found</h1>'))
return(httpResponse(200, savedFile$contentType, savedFile$data))
}
if (matches[2] == 'upload' && identical(req$REQUEST_METHOD, "POST")) {
job <- private$fileUploadContext$getUploadOperation(matches[3])
if (!is.null(job)) {
fileName <- req$HTTP_SHINY_FILE_NAME
fileType <- req$HTTP_SHINY_FILE_TYPE
fileSize <- req$CONTENT_LENGTH
job$fileBegin()
reqInput <- req$rook.input
while (length(buf <- reqInput$read(2^16)) > 0)
job$fileChunk(buf)
job$fileEnd()
return(httpResponse(200, 'text/plain', 'OK'))
}
}
if (matches[2] == 'uploadie' && identical(req$REQUEST_METHOD, "POST")) {
id <- URLdecode(matches[3])
res <- mime::parse_multipart(req)
private$.input$set(id, res[[id]])
return(httpResponse(200, 'text/plain', 'OK'))
}
if (matches[2] == 'download') {
# A bunch of ugliness here. Filenames can be dynamically generated by
# the user code, so we don't know what they'll be in advance. But the
# most reliable way to use non-ASCII filenames for downloads is to
# put the actual filename in the URL. So we will start with URLs in
# the form:
#
# /session/$TOKEN/download/$NAME
#
# When a request matching that pattern is received, we will calculate
# the filename and see if it's non-ASCII; if so, we'll redirect to
#
# /session/$TOKEN/download/$NAME/$FILENAME
#
# And when that pattern is received, we will actually return the file.
# Note that this means the filename and contents could be determined
# a few moments apart from each other (an HTTP roundtrip basically),
# hopefully that won't be enough to matter for anyone.
dlmatches <- regmatches(matches[3],
regexec("^([^/]+)(/[^/]+)?$",
matches[3]))[[1]]
dlname <- URLdecode(dlmatches[2])
download <- self$downloads$get(dlname)
if (is.null(download))
return(httpResponse(404, 'text/html', '<h1>Not Found</h1>'))
filename <- ifelse(is.function(download$filename),
Context$new(getDefaultReactiveDomain(), '[download]')$run(
download$filename
),
download$filename)
# If the URL does not contain the filename, and the desired filename
# contains non-ASCII characters, then do a redirect with the desired
# name tacked on the end.
if (dlmatches[3] == '' && grepl('[^ -~]', filename)) {
return(httpResponse(302, 'text/html', '<h1>Found</h1>', c(
'Location' = sprintf('%s/%s',
URLencode(dlname, TRUE),
URLencode(filename, TRUE)),
'Cache-Control' = 'no-cache')))
}
# Make temp file with the same extension as the user-visible filename.
# If the extension is not used, some functions such as pdf() and zip()
# may append the extension they expect, meaning the data we want will
# be written to a file other than our temp file (e.g. file1231.zip
# instead of file1231.zip).
ext <- tools::file_ext(filename)
if (nzchar(ext))
ext <- paste(".", ext, sep = "")
tmpdata <- tempfile(fileext = ext)
# ..stacktraceon matches with the top-level ..stacktraceoff..
result <- try(shinyCallingHandlers(Context$new(getDefaultReactiveDomain(), '[download]')$run(
function() { ..stacktraceon..(download$func(tmpdata)) }
)), silent = TRUE)
if (inherits(result, 'try-error')) {
unlink(tmpdata)
stop(attr(result, "condition", exact = TRUE))
}
return(httpResponse(
200,
download$contentType %OR% getContentType(filename),
# owned=TRUE means tmpdata will be deleted after response completes
list(file=tmpdata, owned=TRUE),
c(
'Content-Disposition' = ifelse(
dlmatches[3] == '',
'attachment; filename="' %.%
gsub('(["\\\\])', '\\\\\\1', filename) %.% # yes, that many \'s
'"',
'attachment'
),
'Cache-Control'='no-cache')))
}
if (matches[2] == 'dataobj') {
# /session/$TOKEN/dataobj/$NAME
dlmatches <- regmatches(matches[3],
regexec("^([^/]+)(/[^/]+)?$",
matches[3]))[[1]]
dlname <- URLdecode(dlmatches[2])
download <- self$downloads$get(dlname)
return(download$filter(download$data, req))
}
return(httpResponse(404, 'text/html', '<h1>Not Found</h1>'))
},
saveFileUrl = function(name, data, contentType, extra=list()) {
"Creates an entry in the file map for the data, and returns a URL pointing
to the file."
self$files$set(name, list(data=data, contentType=contentType))
return(sprintf('session/%s/file/%s?w=%s&r=%s',
URLencode(self$token, TRUE),
URLencode(name, TRUE),
workerId(),
createUniqueId(8)))
},
# Send a file to the client
fileUrl = function(name, file, contentType='application/octet-stream') {
"Return a URL for a file to be sent to the client. If allowDataUriScheme
is TRUE, then the file will be base64 encoded and embedded in the URL.
Otherwise, a URL pointing to the file will be returned."
bytes <- file.info(file)$size
if (is.na(bytes))
return(NULL)
fileData <- readBin(file, 'raw', n=bytes)
if (isTRUE(private$.clientData$.values$allowDataUriScheme)) {
b64 <- rawToBase64(fileData)
return(paste('data:', contentType, ';base64,', b64, sep=''))
} else {
return(self$saveFileUrl(name, fileData, contentType))
}
},
registerDownload = function(name, filename, contentType, func) {
self$downloads$set(name, list(filename = filename,
contentType = contentType,
func = func))
return(sprintf('session/%s/download/%s?w=%s',
URLencode(self$token, TRUE),
URLencode(name, TRUE),
workerId()))
},
# register a data object on the server side (for datatable or selectize, etc)
registerDataObj = function(name, data, filterFunc) {
# abusing downloads at the moment
self$downloads$set(name, list(data = data, filter = filterFunc))
return(sprintf('session/%s/dataobj/%s?w=%s',
URLencode(self$token, TRUE),
URLencode(name, TRUE),
workerId()))
},
# This function suspends observers for hidden outputs and resumes observers
# for un-hidden outputs.
manageHiddenOutputs = function() {
# Find hidden state for each output, and suspend/resume accordingly
for (outputName in names(private$.outputs)) {
if (private$shouldSuspend(outputName)) {
private$.outputs[[outputName]]$suspend()
} else {
private$.outputs[[outputName]]$resume()
}
}
},
# Set the normal and client data input variables
manageInputs = function(data) {
private$inputReceivedCallbacks$invoke(data)
data_names <- names(data)
# Separate normal input variables from client data input variables
clientdata_idx <- grepl("^.clientdata_", data_names)
# Set normal (non-clientData) input values
private$.input$mset(data[data_names[!clientdata_idx]])
# Strip off .clientdata_ from clientdata input names, and set values
input_clientdata <- data[data_names[clientdata_idx]]
names(input_clientdata) <- sub("^.clientdata_", "",
names(input_clientdata))
private$.clientData$mset(input_clientdata)
},
outputOptions = function(name, ...) {
# If no name supplied, return the list of options for all outputs
if (is.null(name))
return(private$.outputOptions)
if (! name %in% names(private$.outputs))
stop(name, " is not in list of output objects")
opts <- list(...)
# If no options are set, return the options for the specified output
if (length(opts) == 0)
return(private$.outputOptions[[name]])
# Set the appropriate option
validOpts <- c("suspendWhenHidden", "priority")
for (optname in names(opts)) {
if (! optname %in% validOpts)
stop(optname, " is not a valid option")
private$.outputOptions[[name]][[optname]] <- opts[[optname]]
}
# If any changes to suspendWhenHidden, need to re-run manageHiddenOutputs
if ("suspendWhenHidden" %in% names(opts)) {
self$manageHiddenOutputs()
}
if ("priority" %in% names(opts)) {
private$.outputs[[name]]$setPriority(opts[['priority']])
}
invisible()
},
incrementBusyCount = function() {
if (private$busyCount == 0L) {
private$sendMessage(busy = "busy")
}
private$busyCount <- private$busyCount + 1L
},
decrementBusyCount = function() {
private$busyCount <- private$busyCount - 1L
if (private$busyCount == 0L) {
private$sendMessage(busy = "idle")
}
}
),
active = list(
session = function() {
shinyDeprecated(
msg = paste("Attempted to access deprecated shinysession$session object.",
"Please just access the shinysession object directly."),
version = "0.11.1"
)
self
}
)
)
.createOutputWriter <- function(shinysession, ns = identity) {
structure(list(impl=shinysession, ns=ns), class='shinyoutput')
}
#' @export
`$<-.shinyoutput` <- function(x, name, value) {
name <- .subset2(x, 'ns')(name)
label <- deparse(substitute(value))
if (length(substitute(value)) > 1) {
# value is an object consisting of a call and its arguments. Here we want
# to find the source references for the first argument (if there are
# arguments), which generally corresponds to the reactive expression--
# e.g. in renderTable({ x }), { x } is the expression to trace.
attr(label, "srcref") <- srcrefFromShinyCall(substitute(value)[[2]])
srcref <- attr(substitute(value)[[2]], "srcref")
if (length(srcref) > 0)
attr(label, "srcfile") <- srcFileOfRef(srcref[[1]])
}
.subset2(x, 'impl')$defineOutput(name, value, label)
return(invisible(x))
}
#' @export
`[[<-.shinyoutput` <- `$<-.shinyoutput`
#' @export
`$.shinyoutput` <- function(x, name) {
stop("Reading objects from shinyoutput object not allowed.")
}
#' @export
`[[.shinyoutput` <- `$.shinyoutput`
#' @export
`[.shinyoutput` <- function(values, name) {
stop("Single-bracket indexing of shinyoutput object is not allowed.")
}
#' @export
`[<-.shinyoutput` <- function(values, name, value) {
stop("Single-bracket indexing of shinyoutput object is not allowed.")
}
#' Set options for an output object.
#'
#' These are the available options for an output object:
#' \itemize{
#' \item suspendWhenHidden. When \code{TRUE} (the default), the output object
#' will be suspended (not execute) when it is hidden on the web page. When
#' \code{FALSE}, the output object will not suspend when hidden, and if it
#' was already hidden and suspended, then it will resume immediately.
#' \item priority. The priority level of the output object. Queued outputs
#' with higher priority values will execute before those with lower values.
#' }
#'
#' @examples
#' \dontrun{
#' # Get the list of options for all observers within output
#' outputOptions(output)
#'
#' # Disable suspend for output$myplot
#' outputOptions(output, "myplot", suspendWhenHidden = FALSE)
#'
#' # Change priority for output$myplot
#' outputOptions(output, "myplot", priority = 10)
#'
#' # Get the list of options for output$myplot
#' outputOptions(output, "myplot")
#' }
#'
#' @param x A shinyoutput object (typically \code{output}).
#' @param name The name of an output observer in the shinyoutput object.
#' @param ... Options to set for the output observer.
#' @export
outputOptions <- function(x, name, ...) {
if (!inherits(x, "shinyoutput"))
stop("x must be a shinyoutput object.")
name <- .subset2(x, 'ns')(name)
.subset2(x, 'impl')$outputOptions(name, ...)
}
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