ARROW-3731: MVP to read parquet in R library

r/R/read_parquet.R

@@ -0,0 +1,10 @@
+#' Read parquet file from disk
+#' 
+#' @param files a vector of filenames
+#' @export
+read_parquet = function(files) {
+ tables = lapply(files, function(f) {
+ return (as_tibble(shared_ptr(`arrow::Table`, read_parquet_file(f))))
+ })
+ do.call('rbind', tables)
+}

r/configure

@@ -49,7 +49,8 @@ if [ "$INCLUDE_DIR" ] || [ "$LIB_DIR" ]; then
 elif [ "$PKGCONFIG_CFLAGS" ] || [ "$PKGCONFIG_LIBS" ]; then
  echo "Found pkg-config cflags and libs!"
  PKG_CFLAGS=${PKGCONFIG_CFLAGS}
- PKG_LIBS=${PKGCONFIG_LIBS}
+ #PKG_LIBS=${PKGCONFIG_LIBS}
+ PKG_LIBS="-larrow -lparquet" # hard coded! what is the right way to do this?
 elif [[ "$OSTYPE" == "darwin"* ]]; then
  if [ "$(command -v brew)" ]; then
  BREWDIR=$(brew --prefix)

r/src/parquetfilereader.cpp

@@ -0,0 +1,38 @@
+// // Licensed to the Apache Software Foundation (ASF) under one
+// // or more contributor license agreements. See the NOTICE file
+// // distributed with this work for additional information
+// // regarding copyright ownership. The ASF licenses this file
+// // to you under the Apache License, Version 2.0 (the
+// // "License"); you may not use this file except in compliance
+// // with the License. You may obtain a copy of the License at
+// //
+// // http://www.apache.org/licenses/LICENSE-2.0
+// //
+// // Unless required by applicable law or agreed to in writing,
+// // software distributed under the License is distributed on an
+// // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// // KIND, either express or implied. See the License for the
+// // specific language governing permissions and limitations
+// // under the License.
+//
+//
+#include <arrow/api.h>
+#include <arrow/io/api.h>
+#include <parquet/arrow/reader.h>
+#include <parquet/arrow/writer.h>
+#include <parquet/exception.h>
+
+// [[Rcpp::export]]
+std::shared_ptr<arrow::Table> read_parquet_file(std::string filename) {
+ std::shared_ptr<arrow::io::ReadableFile> infile;
+ PARQUET_THROW_NOT_OK(arrow::io::ReadableFile::Open(
+ filename, arrow::default_memory_pool(), &infile));
+
+ std::unique_ptr<parquet::arrow::FileReader> reader;
+ PARQUET_THROW_NOT_OK(
+ parquet::arrow::OpenFile(infile, arrow::default_memory_pool(), &reader));
+ std::shared_ptr<arrow::Table> table;
+ PARQUET_THROW_NOT_OK(reader->ReadTable(&table));
+
+ return table;
+}