Turned routines to preprocess user inputs into S3 methods.

Still needs to be tested.

R/DESCRIPTION

@@ -9,7 +9,9 @@ Description: Split REDCap repeating instruments output into multiple tables.
     This will take raw output from a REDCap export and split it into a base table
     and child tables for each repeating instrument. 
 Depends: R (>= 3.4.0)
-Suggests: RCurl, 
+Suggests: 
+    RCurl, 
+    httr,
     jsonlite,
     testthat
 License: GPL-3
@@ -19,5 +21,5 @@ RoxygenNote: 6.0.1
 URL: https://github.com/SpectrumHealthResearch/REDCapRITS
 BugReports: https://github.com/SpectrumHealthResearch/REDCapRITS/issues
 Collate: 
-    'JSON2data.frame.r'
+    'process_user_input.r'
     'REDCap_split.r'

R/R/JSON2data.frame.r

@@ -1,37 +0,0 @@
-JSON2data.frame <- function (x) {
-
-  if (inherits(x, "data.frame")) {
-
-    return(x)
-
-  } else if (inherits(x, "character")) {
-
-    if (requireNamespace("jsonlite", quietly = TRUE)) {
-
-      return(jsonlite::fromJSON(x))
-
-    } else {
-
-      stop(
-        "The package 'jsonlite' is needed to convert ",
-        deparse(substitute(x)),
-        " into a data frame.",
-        "\n       Either install 'jsonlite' or pass ",
-        deparse(substitute(x)),
-        " as a 'data.frame'.",
-        call. = FALSE
-      )
-
-    }
-
-  } else {
-
-    stop(
-      deparse(substitute(x)),
-      " must be a 'data.frame' or JSON string of class 'character'.",
-      call. = FALSE
-    )
-
-  }
-
-}

R/R/REDCap_split.r

@@ -4,11 +4,12 @@
 #' and child tables for each repeating instrument. Metadata
 #' is used to determine which fields should be included in each resultant table.
 #'
-#' @param records Exported project records. May be a \code{data.frame} or
+#' @param records Exported project records. May be a \code{data.frame},
-#'   \code{character} vector containing JSON from an API call.
+#'   \code{response}, or \code{character} vector containing JSON from an API
-#' @param metadata Project metadata (the data dictionary). May be a
-#'   \code{data.frame} or \code{character} vector containing JSON from an API
 #'   call.
+#' @param metadata Project metadata (the data dictionary). May be a
+#'   \code{data.frame}, \code{response}, or \code{character} vector containing
+#'   JSON from an API call.
 #' @author Paul W. Egeler, M.S., GStat
 #' @examples
 #' \dontrun{
@@ -65,13 +66,13 @@
 #' }
 #' @return A list of \code{"data.frame"}s: one base table and zero or more
 #'   tables for each repeating instrument.
-#' @include JSON2data.frame.r
+#' @include process_user_input.r
 #' @export
 REDCap_split <- function(records, metadata) {
 
   # Process user input
-  records  <- JSON2data.frame(records)
+  records  <- process_user_input(records)
-  metadata <- JSON2data.frame(metadata)
+  metadata <- process_user_input(metadata)
 
   # Get the variable names in the dataset
   vars_in_data <- names(records)

R/R/process_user_input.r

@@ -0,0 +1,53 @@
+process_user_input <- function (x) {
+  UseMethod("process_user_input", x)
+}
+
+process_user_input.default <- function(x, ...) {
+  stop(
+    deparse(substitute(x)),
+    " must be a 'data.frame',",
+    " a 'response',",
+    " or a 'character' vector containing JSON.",
+    call. = FALSE
+  )
+}
+
+process_user_input.data.frame <- function(x, ...) {
+    x
+}
+
+process_user_input.character <- function(x, ...) {
+
+  if (!requireNamespace("jsonlite", quietly = TRUE)) {
+    stop(
+      "The package 'jsonlite' is needed to convert ",
+      deparse(substitute(x)),
+      " into a data frame.",
+      "\n       Either install 'jsonlite' or pass ",
+      deparse(substitute(x)),
+      " as a 'data.frame'.",
+      call. = FALSE
+    )
+  }
+
+  jsonlite::fromJSON(x)
+
+}
+
+process_user_input.response <- function(x, ...) {
+
+  if (!requireNamespace("httr", quietly = TRUE)) {
+    stop(
+      "The package 'httr' is needed to convert ",
+      deparse(substitute(x)),
+      " into a data frame.",
+      "\n       Either install 'httr' or pass ",
+      deparse(substitute(x)),
+      " as a 'data.frame'.",
+      call. = FALSE
+    )
+  }
+
+  httr::content(x, as = "text")
+
+}

R/man/REDCap_split.Rd

@@ -7,12 +7,13 @@
 REDCap_split(records, metadata)
 }
 \arguments{
-\item{records}{Exported project records. May be a \code{data.frame} or
+\item{records}{Exported project records. May be a \code{data.frame},
-\code{character} vector containing JSON from an API call.}
+\code{response}, or \code{character} vector containing JSON from an API
+call.}
 
 \item{metadata}{Project metadata (the data dictionary). May be a
-\code{data.frame} or \code{character} vector containing JSON from an API
+\code{data.frame}, \code{response}, or \code{character} vector containing
-call.}
+JSON from an API call.}
 }
 \value{
 A list of \code{"data.frame"}s: one base table and zero or more