Add an update.dataset() function

R/datasets.R

@@ -228,3 +228,43 @@ delete.datasets <- function(ws, name, host){
   refresh(ws, "datasets")
   ans
 }
+
+#' Update an existing R data frame in an AzureML workspace.
+#'
+#' Update an existing R data frame to an AzureML workspace using the \code{GenericTSV} format.
+#' 
+#' @inheritParams refresh
+#' @param x An R data frame object
+#' @param name A character name for an existing AzureML dataset
+#' @param description An optional character description of the dataset, description for the existing dataset will be used if none provided here
+#' @param family_id An optional AzureML family identifier, family identifier for the existing dataset will be used if none provided here
+#' @param ... Optional additional options passed to \code{write.table}
+#' @note The additional \code{\link[utils]{write.table}} options may not include \code{sep} or \code{row.names} or \code{file}, but any other options are accepted.
+#' 
+#' @return A single-row data frame of "Datasets" class that corresponds to the updated object now available in ws$datasets.
+#' @importFrom curl curl_escape new_handle handle_setheaders handle_reset handle_setopt curl_fetch_memory
+#' @importFrom jsonlite fromJSON
+#' @export
+#' @family dataset functions
+#' @example inst/examples/example_update.R
+
+update.dataset <- function(x, ws, name, description = "", family_id = "", ...)
+{
+
+  # take care of exceptions from delete: it's Microsoft dataset or dataset does not exist
+  if (name %in% datasets(ws, filter = "samples")$Name) stop("Update not allowed for Microsoft sample datasets.") 
+  else if (!(name %in% datasets(ws, filter = "my datasets")$Name)) stop("The dataset named '", name, "' does not exist.")
+
+  # check to make sure the existing file is in GenericTSV format
+  if (tolower(ws$datasets$DataTypeId[ws$datasets$Name == name]) != "generictsv") stop("The existing dataset is not of type GenericTSV.")
+
+  # use description and family_id from the existing dataset if no new values are provided
+  if (description == "") description = ws$datasets$Description[ws$datasets$Name == name]
+  if (family_id == "") family_id = ws$datasets$FamilyId[ws$datasets$Name == name]
+
+  # delete existing data
+  dr <- delete.datasets(ws, name)
+
+  # upload
+  upload.dataset(x, ws, name, description, family_id)
+}

inst/examples/example_update.R

@@ -0,0 +1,17 @@
+\dontrun{
+  library(AzureML)
+
+  ws <- workspace()
+
+  # Upload the R airquality data.frame to the workspace.
+  upload.dataset(airquality, ws, "airquality")
+
+  # Make an update by using only the first 10 rows
+  update.dataset(airquality[1:10, ], ws, "airquality")
+
+  # Download the updated dataset to check its content
+  download.datasets(ws, name = "airquality")
+
+  # Now delete what we've just uploaded
+  delete.datasets(ws, "airquality")
+}