[SPARK-20195][SPARKR][SQL] add createTable catalog API and deprecate createExternalTable

## What changes were proposed in this pull request?

Following up on apache#17483, add createTable (which is new in 2.2.0) and deprecate createExternalTable, plus a number of minor fixes

## How was this patch tested?

manual, unit tests

Author: Felix Cheung <[email protected]>

Closes apache#17511 from felixcheung/rceatetable.

Author: felixcheung

R/pkg/NAMESPACE

@@ -361,6 +361,7 @@ export("as.DataFrame",
        "clearCache",
        "createDataFrame",
        "createExternalTable",
+       "createTable",
        "currentDatabase",
        "dropTempTable",
        "dropTempView",

R/pkg/R/DataFrame.R

@@ -557,7 +557,7 @@ setMethod("insertInto",
             jmode <- convertToJSaveMode(ifelse(overwrite, "overwrite", "append"))
             write <- callJMethod(x@sdf, "write")
             write <- callJMethod(write, "mode", jmode)
-            callJMethod(write, "insertInto", tableName)
+            invisible(callJMethod(write, "insertInto", tableName))
           })
 
 #' Cache
@@ -2894,7 +2894,7 @@ setMethod("saveAsTable",
             write <- callJMethod(write, "format", source)
             write <- callJMethod(write, "mode", jmode)
             write <- callJMethod(write, "options", options)
-            callJMethod(write, "saveAsTable", tableName)
+            invisible(callJMethod(write, "saveAsTable", tableName))
           })
 
 #' summary

R/pkg/R/catalog.R

@@ -17,7 +17,7 @@
 
 # catalog.R: SparkSession catalog functions
 
-#' Create an external table
+#' (Deprecated) Create an external table
 #'
 #' Creates an external table based on the dataset in a data source,
 #' Returns a SparkDataFrame associated with the external table.
@@ -29,10 +29,11 @@
 #' @param tableName a name of the table.
 #' @param path the path of files to load.
 #' @param source the name of external data source.
-#' @param schema the schema of the data for certain data source.
+#' @param schema the schema of the data required for some data sources.
 #' @param ... additional argument(s) passed to the method.
 #' @return A SparkDataFrame.
-#' @rdname createExternalTable
+#' @rdname createExternalTable-deprecated
+#' @seealso \link{createTable}
 #' @export
 #' @examples
 #'\dontrun{
@@ -43,24 +44,64 @@
 #' @method createExternalTable default
 #' @note createExternalTable since 1.4.0
 createExternalTable.default <- function(tableName, path = NULL, source = NULL, schema = NULL, ...) {
+  .Deprecated("createTable", old = "createExternalTable")
+  createTable(tableName, path, source, schema, ...)
+}
+
+createExternalTable <- function(x, ...) {
+  dispatchFunc("createExternalTable(tableName, path = NULL, source = NULL, ...)", x, ...)
+}
+
+#' Creates a table based on the dataset in a data source
+#'
+#' Creates a table based on the dataset in a data source. Returns a SparkDataFrame associated with
+#' the table.
+#'
+#' The data source is specified by the \code{source} and a set of options(...).
+#' If \code{source} is not specified, the default data source configured by
+#' "spark.sql.sources.default" will be used. When a \code{path} is specified, an external table is
+#' created from the data at the given path. Otherwise a managed table is created.
+#'
+#' @param tableName the qualified or unqualified name that designates a table. If no database
+#'                  identifier is provided, it refers to a table in the current database.
+#' @param path (optional) the path of files to load.
+#' @param source (optional) the name of the data source.
+#' @param schema (optional) the schema of the data required for some data sources.
+#' @param ... additional named parameters as options for the data source.
+#' @return A SparkDataFrame.
+#' @rdname createTable
+#' @seealso \link{createExternalTable}
+#' @export
+#' @examples
+#'\dontrun{
+#' sparkR.session()
+#' df <- createTable("myjson", path="path/to/json", source="json", schema)
+#'
+#' createTable("people", source = "json", schema = schema)
+#' insertInto(df, "people")
+#' }
+#' @name createTable
+#' @note createTable since 2.2.0
+createTable <- function(tableName, path = NULL, source = NULL, schema = NULL, ...) {
   sparkSession <- getSparkSession()
   options <- varargsToStrEnv(...)
   if (!is.null(path)) {
     options[["path"]] <- path
   }
+  if (is.null(source)) {
+    source <- getDefaultSqlSource()
+  }
   catalog <- callJMethod(sparkSession, "catalog")
   if (is.null(schema)) {
-    sdf <- callJMethod(catalog, "createExternalTable", tableName, source, options)
+    sdf <- callJMethod(catalog, "createTable", tableName, source, options)
+  } else if (class(schema) == "structType") {
+    sdf <- callJMethod(catalog, "createTable", tableName, source, schema$jobj, options)
   } else {
-    sdf <- callJMethod(catalog, "createExternalTable", tableName, source, schema$jobj, options)
+    stop("schema must be a structType.")
   }
   dataFrame(sdf)
 }
 
-createExternalTable <- function(x, ...) {
-  dispatchFunc("createExternalTable(tableName, path = NULL, source = NULL, ...)", x, ...)
-}
-
 #' Cache Table
 #'
 #' Caches the specified table in-memory.

R/pkg/inst/tests/testthat/test_sparkSQL.R

@@ -281,7 +281,7 @@ test_that("create DataFrame from RDD", {
   setHiveContext(sc)
   sql("CREATE TABLE people (name string, age double, height float)")
   df <- read.df(jsonPathNa, "json", schema)
-  invisible(insertInto(df, "people"))
+  insertInto(df, "people")
   expect_equal(collect(sql("SELECT age from people WHERE name = 'Bob'"))$age,
                c(16))
   expect_equal(collect(sql("SELECT height from people WHERE name ='Bob'"))$height,
@@ -1268,33 +1268,43 @@ test_that("column calculation", {
 
 test_that("test HiveContext", {
   setHiveContext(sc)
-  df <- createExternalTable("json", jsonPath, "json")
+
+  schema <- structType(structField("name", "string"), structField("age", "integer"),
+                       structField("height", "float"))
+  createTable("people", source = "json", schema = schema)
+  df <- read.df(jsonPathNa, "json", schema)
+  insertInto(df, "people")
+  expect_equal(collect(sql("SELECT age from people WHERE name = 'Bob'"))$age, c(16))
+  sql("DROP TABLE people")
+
+  df <- createTable("json", jsonPath, "json")
   expect_is(df, "SparkDataFrame")
   expect_equal(count(df), 3)
   df2 <- sql("select * from json")
   expect_is(df2, "SparkDataFrame")
   expect_equal(count(df2), 3)
 
   jsonPath2 <- tempfile(pattern = "sparkr-test", fileext = ".tmp")
-  invisible(saveAsTable(df, "json2", "json", "append", path = jsonPath2))
+  saveAsTable(df, "json2", "json", "append", path = jsonPath2)
   df3 <- sql("select * from json2")
   expect_is(df3, "SparkDataFrame")
   expect_equal(count(df3), 3)
   unlink(jsonPath2)
 
   hivetestDataPath <- tempfile(pattern = "sparkr-test", fileext = ".tmp")
-  invisible(saveAsTable(df, "hivetestbl", path = hivetestDataPath))
+  saveAsTable(df, "hivetestbl", path = hivetestDataPath)
   df4 <- sql("select * from hivetestbl")
   expect_is(df4, "SparkDataFrame")
   expect_equal(count(df4), 3)
   unlink(hivetestDataPath)
 
   parquetDataPath <- tempfile(pattern = "sparkr-test", fileext = ".tmp")
-  invisible(saveAsTable(df, "parquetest", "parquet", mode = "overwrite", path = parquetDataPath))
+  saveAsTable(df, "parquetest", "parquet", mode = "overwrite", path = parquetDataPath)
   df5 <- sql("select * from parquetest")
   expect_is(df5, "SparkDataFrame")
   expect_equal(count(df5), 3)
   unlink(parquetDataPath)
+
   unsetHiveContext()
 })