Files
shiny/R/shinywrappers.R
Joe Cheng e9fc873c8d Restore HTML generating functions
These functions were temporarily ripped out of Shiny and moved
to the htmltools package. We've discovered that it's safe to
keep including them in shiny; as long as the functions in shiny
and the functions in htmltools are identical, the user won't
receive a conflict warning.
2014-05-29 14:00:48 -07:00

632 lines
23 KiB
R

globalVariables('func')
#' Mark a function as a render function
#'
#' Should be called by implementers of \code{renderXXX} functions in order to
#' mark their return values as Shiny render functions, and to provide a hint to
#' Shiny regarding what UI function is most commonly used with this type of
#' render function. This can be used in R Markdown documents to create complete
#' output widgets out of just the render function.
#'
#' @param uiFunc A function that renders Shiny UI. Must take a single argument:
#' an output ID.
#' @param renderFunc A function that is suitable for assigning to a Shiny output
#' slot.
#' @return The \code{renderFunc} function, with annotations.
#'
#' @export
markRenderFunction <- function(uiFunc, renderFunc) {
class(renderFunc) <- c("shiny.render.function", "function")
attr(renderFunc, "outputFunc") <- uiFunc
renderFunc
}
useRenderFunction <- function(renderFunc) {
outputFunction <- attr(renderFunc, "outputFunc")
id <- createUniqueId(8, "out")
o <- getDefaultReactiveDomain()$output
if (!is.null(o))
o[[id]] <- renderFunc
return(outputFunction(id))
}
#' @S3method as.tags shiny.render.function
as.tags.shiny.render.function <- function(x, ...) {
useRenderFunction(x)
}
#' Plot Output
#'
#' Renders a reactive plot that is suitable for assigning to an \code{output}
#' slot.
#'
#' The corresponding HTML output tag should be \code{div} or \code{img} and have
#' the CSS class name \code{shiny-plot-output}.
#'
#' @seealso For more details on how the plots are generated, and how to control
#' the output, see \code{\link{plotPNG}}.
#'
#' @param expr An expression that generates a plot.
#' @param width The width of the rendered plot, in pixels; or \code{'auto'} to
#' use the \code{offsetWidth} of the HTML element that is bound to this plot.
#' You can also pass in a function that returns the width in pixels or
#' \code{'auto'}; in the body of the function you may reference reactive
#' values and functions.
#' @param height The height of the rendered plot, in pixels; or \code{'auto'} to
#' use the \code{offsetHeight} of the HTML element that is bound to this plot.
#' You can also pass in a function that returns the width in pixels or
#' \code{'auto'}; in the body of the function you may reference reactive
#' values and functions.
#' @param res Resolution of resulting plot, in pixels per inch. This value is
#' passed to \code{\link{png}}. Note that this affects the resolution of PNG
#' rendering in R; it won't change the actual ppi of the browser.
#' @param ... Arguments to be passed through to \code{\link[grDevices]{png}}.
#' These can be used to set the width, height, background color, etc.
#' @param env The environment in which to evaluate \code{expr}.
#' @param quoted Is \code{expr} a quoted expression (with \code{quote()})? This
#' is useful if you want to save an expression in a variable.
#' @param func A function that generates a plot (deprecated; use \code{expr}
#' instead).
#'
#' @export
renderPlot <- function(expr, width='auto', height='auto', res=72, ...,
env=parent.frame(), quoted=FALSE, func=NULL) {
if (!is.null(func)) {
shinyDeprecated(msg="renderPlot: argument 'func' is deprecated. Please use 'expr' instead.")
} else {
installExprFunction(expr, "func", env, quoted)
}
args <- list(...)
if (is.function(width))
widthWrapper <- reactive({ width() })
else
widthWrapper <- NULL
if (is.function(height))
heightWrapper <- reactive({ height() })
else
heightWrapper <- NULL
# If renderPlot isn't going to adapt to the height of the div, then the
# div needs to adapt to the height of renderPlot. By default, plotOutput
# sets the height to 400px, so to make it adapt we need to override it
# with NULL.
outputFunc <- if (identical(height, 'auto'))
plotOutput
else
function(outputId) plotOutput(outputId, height = NULL)
return(markRenderFunction(outputFunc, function(shinysession, name, ...) {
if (!is.null(widthWrapper))
width <- widthWrapper()
if (!is.null(heightWrapper))
height <- heightWrapper()
# Note that these are reactive calls. A change to the width and height
# will inherently cause a reactive plot to redraw (unless width and
# height were explicitly specified).
prefix <- 'output_'
if (width == 'auto')
width <- shinysession$clientData[[paste(prefix, name, '_width', sep='')]];
if (height == 'auto')
height <- shinysession$clientData[[paste(prefix, name, '_height', sep='')]];
if (is.null(width) || is.null(height) || width <= 0 || height <= 0)
return(NULL)
# Resolution multiplier
pixelratio <- shinysession$clientData$pixelratio
if (is.null(pixelratio))
pixelratio <- 1
coordmap <- NULL
plotFunc <- function() {
# Actually perform the plotting
result <- withVisible(func())
if (result$visible) {
# Use capture.output to squelch printing to the actual console; we
# are only interested in plot output
capture.output(print(result$value))
}
# Now capture some graphics device info before we close it
usrCoords <- par('usr')
usrBounds <- usrCoords
if (par('xlog')) {
usrBounds[c(1,2)] <- 10 ^ usrBounds[c(1,2)]
}
if (par('ylog')) {
usrBounds[c(3,4)] <- 10 ^ usrBounds[c(3,4)]
}
coordmap <<- list(
usr = c(
left = usrCoords[1],
right = usrCoords[2],
bottom = usrCoords[3],
top = usrCoords[4]
),
# The bounds of the plot area, in DOM pixels
bounds = c(
left = grconvertX(usrBounds[1], 'user', 'nfc') * width,
right = grconvertX(usrBounds[2], 'user', 'nfc') * width,
bottom = (1-grconvertY(usrBounds[3], 'user', 'nfc')) * height,
top = (1-grconvertY(usrBounds[4], 'user', 'nfc')) * height
),
log = c(
x = par('xlog'),
y = par('ylog')
),
pixelratio = pixelratio
)
}
outfile <- do.call(plotPNG, c(plotFunc, width=width*pixelratio,
height=height*pixelratio, res=res*pixelratio, args))
on.exit(unlink(outfile))
# Return a list of attributes for the img
return(list(
src=shinysession$fileUrl(name, outfile, contentType='image/png'),
width=width, height=height, coordmap=coordmap
))
}))
}
#' Image file output
#'
#' Renders a reactive image that is suitable for assigning to an \code{output}
#' slot.
#'
#' The expression \code{expr} must return a list containing the attributes for
#' the \code{img} object on the client web page. For the image to display,
#' properly, the list must have at least one entry, \code{src}, which is the
#' path to the image file. It may also useful to have a \code{contentType}
#' entry specifying the MIME type of the image. If one is not provided,
#' \code{renderImage} will try to autodetect the type, based on the file
#' extension.
#'
#' Other elements such as \code{width}, \code{height}, \code{class}, and
#' \code{alt}, can also be added to the list, and they will be used as
#' attributes in the \code{img} object.
#'
#' The corresponding HTML output tag should be \code{div} or \code{img} and have
#' the CSS class name \code{shiny-image-output}.
#'
#' @seealso For more details on how the images are generated, and how to control
#' the output, see \code{\link{plotPNG}}.
#'
#' @param expr An expression that returns a list.
#' @param env The environment in which to evaluate \code{expr}.
#' @param quoted Is \code{expr} a quoted expression (with \code{quote()})? This
#' is useful if you want to save an expression in a variable.
#' @param deleteFile Should the file in \code{func()$src} be deleted after
#' it is sent to the client browser? Generally speaking, if the image is a
#' temp file generated within \code{func}, then this should be \code{TRUE};
#' if the image is not a temp file, this should be \code{FALSE}.
#'
#' @export
#'
#' @examples
#' \dontrun{
#'
#' shinyServer(function(input, output, clientData) {
#'
#' # A plot of fixed size
#' output$plot1 <- renderImage({
#' # A temp file to save the output. It will be deleted after renderImage
#' # sends it, because deleteFile=TRUE.
#' outfile <- tempfile(fileext='.png')
#'
#' # Generate a png
#' png(outfile, width=400, height=400)
#' hist(rnorm(input$n))
#' dev.off()
#'
#' # Return a list
#' list(src = outfile,
#' alt = "This is alternate text")
#' }, deleteFile = TRUE)
#'
#' # A dynamically-sized plot
#' output$plot2 <- renderImage({
#' # Read plot2's width and height. These are reactive values, so this
#' # expression will re-run whenever these values change.
#' width <- clientData$output_plot2_width
#' height <- clientData$output_plot2_height
#'
#' # A temp file to save the output.
#' outfile <- tempfile(fileext='.png')
#'
#' png(outfile, width=width, height=height)
#' hist(rnorm(input$obs))
#' dev.off()
#'
#' # Return a list containing the filename
#' list(src = outfile,
#' width = width,
#' height = height,
#' alt = "This is alternate text")
#' }, deleteFile = TRUE)
#'
#' # Send a pre-rendered image, and don't delete the image after sending it
#' output$plot3 <- renderImage({
#' # When input$n is 1, filename is ./images/image1.jpeg
#' filename <- normalizePath(file.path('./images',
#' paste('image', input$n, '.jpeg', sep='')))
#'
#' # Return a list containing the filename
#' list(src = filename)
#' }, deleteFile = FALSE)
#' })
#'
#' }
renderImage <- function(expr, env=parent.frame(), quoted=FALSE,
deleteFile=TRUE) {
installExprFunction(expr, "func", env, quoted)
return(markRenderFunction(imageOutput, function(shinysession, name, ...) {
imageinfo <- func()
# Should the file be deleted after being sent? If .deleteFile not set or if
# TRUE, then delete; otherwise don't delete.
if (deleteFile) {
on.exit(unlink(imageinfo$src))
}
# If contentType not specified, autodetect based on extension
if (is.null(imageinfo$contentType)) {
contentType <- getContentType(sub('^.*\\.', '', basename(imageinfo$src)))
} else {
contentType <- imageinfo$contentType
}
# Extra values are everything in imageinfo except 'src' and 'contentType'
extra_attr <- imageinfo[!names(imageinfo) %in% c('src', 'contentType')]
# Return a list with src, and other img attributes
c(src = shinysession$fileUrl(name, file=imageinfo$src, contentType=contentType),
extra_attr)
}))
}
#' Table Output
#'
#' Creates a reactive table that is suitable for assigning to an \code{output}
#' slot.
#'
#' The corresponding HTML output tag should be \code{div} and have the CSS class
#' name \code{shiny-html-output}.
#'
#' @param expr An expression that returns an R object that can be used with
#' \code{\link[xtable]{xtable}}.
#' @param ... Arguments to be passed through to \code{\link[xtable]{xtable}} and
#' \code{\link[xtable]{print.xtable}}.
#' @param env The environment in which to evaluate \code{expr}.
#' @param quoted Is \code{expr} a quoted expression (with \code{quote()})? This
#' is useful if you want to save an expression in a variable.
#' @param func A function that returns an R object that can be used with
#' \code{\link[xtable]{xtable}} (deprecated; use \code{expr} instead).
#'
#' @export
renderTable <- function(expr, ..., env=parent.frame(), quoted=FALSE, func=NULL) {
if (!is.null(func)) {
shinyDeprecated(msg="renderTable: argument 'func' is deprecated. Please use 'expr' instead.")
} else {
installExprFunction(expr, "func", env, quoted)
}
markRenderFunction(tableOutput, function() {
classNames <- getOption('shiny.table.class', 'data table table-bordered table-condensed')
data <- func()
if (is.null(data) || identical(data, data.frame()))
return("")
return(paste(
capture.output(
print(xtable(data, ...),
type='html',
html.table.attributes=paste('class="',
htmlEscape(classNames, TRUE),
'"',
sep=''), ...)),
collapse="\n"))
})
}
#' Printable Output
#'
#' Makes a reactive version of the given function that captures any printed
#' output, and also captures its printable result (unless
#' \code{\link{invisible}}), into a string. The resulting function is suitable
#' for assigning to an \code{output} slot.
#'
#' The corresponding HTML output tag can be anything (though \code{pre} is
#' recommended if you need a monospace font and whitespace preserved) and should
#' have the CSS class name \code{shiny-text-output}.
#'
#' The result of executing \code{func} will be printed inside a
#' \code{\link[utils]{capture.output}} call.
#'
#' Note that unlike most other Shiny output functions, if the given function
#' returns \code{NULL} then \code{NULL} will actually be visible in the output.
#' To display nothing, make your function return \code{\link{invisible}()}.
#'
#' @param expr An expression that may print output and/or return a printable R
#' object.
#' @param env The environment in which to evaluate \code{expr}.
#' @param quoted Is \code{expr} a quoted expression (with \code{quote()})? This
#' @param func A function that may print output and/or return a printable R
#' object (deprecated; use \code{expr} instead).
#' @param width The value for \code{\link{options}('width')}.
#' @seealso \code{\link{renderText}} for displaying the value returned from a
#' function, instead of the printed output.
#'
#' @example res/text-example.R
#'
#' @export
renderPrint <- function(expr, env = parent.frame(), quoted = FALSE, func = NULL,
width = getOption('width')) {
if (!is.null(func)) {
shinyDeprecated(msg="renderPrint: argument 'func' is deprecated. Please use 'expr' instead.")
} else {
installExprFunction(expr, "func", env, quoted)
}
markRenderFunction(verbatimTextOutput, function() {
op <- options(width = width)
on.exit(options(op), add = TRUE)
paste(capture.output(func()), collapse = "\n")
})
}
#' Text Output
#'
#' Makes a reactive version of the given function that also uses
#' \code{\link[base]{cat}} to turn its result into a single-element character
#' vector.
#'
#' The corresponding HTML output tag can be anything (though \code{pre} is
#' recommended if you need a monospace font and whitespace preserved) and should
#' have the CSS class name \code{shiny-text-output}.
#'
#' The result of executing \code{func} will passed to \code{cat}, inside a
#' \code{\link[utils]{capture.output}} call.
#'
#' @param expr An expression that returns an R object that can be used as an
#' argument to \code{cat}.
#' @param env The environment in which to evaluate \code{expr}.
#' @param quoted Is \code{expr} a quoted expression (with \code{quote()})? This
#' is useful if you want to save an expression in a variable.
#' @param func A function that returns an R object that can be used as an
#' argument to \code{cat}.(deprecated; use \code{expr} instead).
#'
#' @seealso \code{\link{renderPrint}} for capturing the print output of a
#' function, rather than the returned text value.
#'
#' @example res/text-example.R
#'
#' @export
renderText <- function(expr, env=parent.frame(), quoted=FALSE, func=NULL) {
if (!is.null(func)) {
shinyDeprecated(msg="renderText: argument 'func' is deprecated. Please use 'expr' instead.")
} else {
installExprFunction(expr, "func", env, quoted)
}
markRenderFunction(textOutput, function() {
value <- func()
return(paste(capture.output(cat(value)), collapse="\n"))
})
}
#' UI Output
#'
#' \bold{Experimental feature.} Makes a reactive version of a function that
#' generates HTML using the Shiny UI library.
#'
#' The corresponding HTML output tag should be \code{div} and have the CSS class
#' name \code{shiny-html-output} (or use \code{\link{uiOutput}}).
#'
#' @param expr An expression that returns a Shiny tag object, \code{\link{HTML}},
#' or a list of such objects.
#' @param env The environment in which to evaluate \code{expr}.
#' @param quoted Is \code{expr} a quoted expression (with \code{quote()})? This
#' is useful if you want to save an expression in a variable.
#' @param func A function that returns a Shiny tag object, \code{\link{HTML}},
#' or a list of such objects (deprecated; use \code{expr} instead).
#'
#' @seealso conditionalPanel
#'
#' @export
#' @examples
#' \dontrun{
#' output$moreControls <- renderUI({
#' list(
#'
#' )
#' })
#' }
renderUI <- function(expr, env=parent.frame(), quoted=FALSE, func=NULL) {
if (!is.null(func)) {
shinyDeprecated(msg="renderUI: argument 'func' is deprecated. Please use 'expr' instead.")
} else {
installExprFunction(expr, "func", env, quoted)
}
markRenderFunction(uiOutput, function(shinysession, name, ...) {
result <- func()
if (is.null(result) || length(result) == 0)
return(NULL)
result <- takeSingletons(result, shinysession$singletons, desingleton=FALSE)$ui
result <- surroundSingletons(result)
dependencies <- lapply(resolveDependencies(findDependencies(result)),
createWebDependency)
names(dependencies) <- NULL
# renderTags returns a list with head, singletons, and html
output <- list(
html = doRenderTags(result),
deps = dependencies
)
return(output)
})
}
#' File Downloads
#'
#' Allows content from the Shiny application to be made available to the user as
#' file downloads (for example, downloading the currently visible data as a CSV
#' file). Both filename and contents can be calculated dynamically at the time
#' the user initiates the download. Assign the return value to a slot on
#' \code{output} in your server function, and in the UI use
#' \code{\link{downloadButton}} or \code{\link{downloadLink}} to make the
#' download available.
#'
#' @param filename A string of the filename, including extension, that the
#' user's web browser should default to when downloading the file; or a
#' function that returns such a string. (Reactive values and functions may be
#' used from this function.)
#' @param content A function that takes a single argument \code{file} that is a
#' file path (string) of a nonexistent temp file, and writes the content to
#' that file path. (Reactive values and functions may be used from this
#' function.)
#' @param contentType A string of the download's
#' \href{http://en.wikipedia.org/wiki/Internet_media_type}{content type}, for
#' example \code{"text/csv"} or \code{"image/png"}. If \code{NULL} or
#' \code{NA}, the content type will be guessed based on the filename
#' extension, or \code{application/octet-stream} if the extension is unknown.
#'
#' @examples
#' \dontrun{
#' # In server.R:
#' output$downloadData <- downloadHandler(
#' filename = function() {
#' paste('data-', Sys.Date(), '.csv', sep='')
#' },
#' content = function(file) {
#' write.csv(data, file)
#' }
#' )
#'
#' # In ui.R:
#' downloadLink('downloadData', 'Download')
#' }
#'
#' @export
downloadHandler <- function(filename, content, contentType=NA) {
return(markRenderFunction(downloadButton, function(shinysession, name, ...) {
shinysession$registerDownload(name, filename, contentType, content)
}))
}
#' Table output with the JavaScript library DataTables
#'
#' Makes a reactive version of the given function that returns a data frame (or
#' matrix), which will be rendered with the DataTables library. Paging,
#' searching, filtering, and sorting can be done on the R side using Shiny as
#' the server infrastructure.
#'
#' For the \code{options} argument, the character elements that have the class
#' \code{"AsIs"} (usually returned from \code{\link{I}()}) will be evaluated in
#' JavaScript. This is useful when the type of the option value is not supported
#' in JSON, e.g., a JavaScript function, which can be obtained by evaluating a
#' character string.
#' @param expr An expression that returns a data frame or a matrix.
#' @param options A list of initialization options to be passed to DataTables,
#' or a function to return such a list.
#' @param searchDelay The delay for searching, in milliseconds (to avoid too
#' frequent search requests).
#' @param callback A JavaScript function to be applied to the DataTable object.
#' This is useful for DataTables plug-ins, which often require the DataTable
#' instance to be available (\url{http://datatables.net/extras/}).
#' @references \url{http://datatables.net}
#' @export
#' @inheritParams renderPlot
#' @examples # pass a callback function to DataTables using I()
#' renderDataTable(iris,
#' options = list(
#' iDisplayLength = 5,
#' fnInitComplete = I("function(oSettings, json) {alert('Done.');}")
#' )
#' )
renderDataTable <- function(expr, options = NULL, searchDelay = 500,
callback = 'function(oTable) {}',
env = parent.frame(), quoted = FALSE) {
installExprFunction(expr, "func", env, quoted)
markRenderFunction(dataTableOutput, function(shinysession, name, ...) {
res <- checkAsIs(if (is.function(options)) options() else options)
data <- func()
if (length(dim(data)) != 2) return() # expects a rectangular data object
action <- shinysession$registerDataObj(name, data, dataTablesJSON)
list(
colnames = colnames(data), action = action, options = res$options,
evalOptions = if (length(res$eval)) I(res$eval), searchDelay = searchDelay,
callback = paste(callback, collapse = '\n')
)
})
}
# Deprecated functions ------------------------------------------------------
#' Plot output (deprecated)
#'
#' See \code{\link{renderPlot}}.
#' @param func A function.
#' @param width Width.
#' @param height Height.
#' @param ... Other arguments to pass on.
#' @export
reactivePlot <- function(func, width='auto', height='auto', ...) {
shinyDeprecated(new="renderPlot")
renderPlot({ func() }, width=width, height=height, ...)
}
#' Table output (deprecated)
#'
#' See \code{\link{renderTable}}.
#' @param func A function.
#' @param ... Other arguments to pass on.
#' @export
reactiveTable <- function(func, ...) {
shinyDeprecated(new="renderTable")
renderTable({ func() })
}
#' Print output (deprecated)
#'
#' See \code{\link{renderPrint}}.
#' @param func A function.
#' @export
reactivePrint <- function(func) {
shinyDeprecated(new="renderPrint")
renderPrint({ func() })
}
#' UI output (deprecated)
#'
#' See \code{\link{renderUI}}.
#' @param func A function.
#' @export
reactiveUI <- function(func) {
shinyDeprecated(new="renderUI")
renderUI({ func() })
}
#' Text output (deprecated)
#'
#' See \code{\link{renderText}}.
#' @param func A function.
#' @export
reactiveText <- function(func) {
shinyDeprecated(new="renderText")
renderText({ func() })
}