content: /*
   * 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.
   */
  package org.apache.beam.it.gcp.artifacts.utils;
  
  import java.io.ByteArrayInputStream;
  import java.io.File;
  import java.io.IOException;
  import java.nio.file.Files;
  import java.util.ArrayList;
  import java.util.List;
  import org.apache.avro.Schema;
  import org.apache.avro.generic.GenericRecord;
  import org.apache.hadoop.fs.Path;
  import org.apache.parquet.avro.AvroParquetReader;
  import org.apache.parquet.avro.AvroParquetWriter;
  import org.apache.parquet.hadoop.ParquetReader;
  import org.apache.parquet.hadoop.ParquetWriter;
  import org.apache.parquet.io.DelegatingSeekableInputStream;
  import org.apache.parquet.io.InputFile;
  import org.apache.parquet.io.SeekableInputStream;
  
  /**
   * The {@link ParquetTestUtil} class provides common utilities used for executing tests that involve
   * Parquet.
   */
  public class ParquetTestUtil {
  
    /**
     * Create Parquet file for the given schema and records list.
     *
     * @param schema Schema to use.
     * @param records Records to write to the sink.
     * @return Byte array that represents the content.
     */
    public static byte[] createParquetFile(Schema schema, List<GenericRecord> records)
        throws IOException {
  
      File tempFile = createTempFile();
      Path file = new Path(tempFile.getPath());
  
      AvroParquetWriter.Builder<GenericRecord> builder = AvroParquetWriter.builder(file);
      ParquetWriter<GenericRecord> parquetWriter = builder.withSchema(schema).build();
      for (GenericRecord record : records) {
        parquetWriter.write(record);
      }
      parquetWriter.close();
  
      return Files.readAllBytes(tempFile.toPath());
    }
  
    /**
     * Read Parquet records to a list of {@link GenericRecord}.
     *
     * @param contents Byte array with contents to read.
     * @return A list with all records.
     */
    public static List<GenericRecord> readRecords(byte[] contents) throws IOException {
      List<GenericRecord> records = new ArrayList<>();
  
      try (ParquetReader<GenericRecord> reader =
          AvroParquetReader.<GenericRecord>builder(new ParquetByteArrayInput(contents)).build()) {
        GenericRecord record;
        while ((record = reader.read()) != null) {
          records.add(record);
        }
      }
      return records;
    }
  
    private static File createTempFile() throws IOException {
      File tempFile = File.createTempFile(ParquetTestUtil.class.getSimpleName(), ".tmp");
      tempFile.deleteOnExit();
      boolean unused = tempFile.delete();
      return tempFile;
    }
  
    static class ParquetByteArrayInput implements InputFile {
      private final byte[] data;
  
      private static class SeekByteArray extends ByteArrayInputStream {
        public SeekByteArray(byte[] buf) {
          super(buf);
        }
  
        public void setPos(int pos) {
          this.pos = pos;
        }
  
        public int getPos() {
          return this.pos;
        }
      }
  
      public ParquetByteArrayInput(byte[] data) {
        this.data = data;
      }
  
      @Override
      public long getLength() {
        return this.data.length;
      }
  
      @Override
      public SeekableInputStream newStream() throws IOException {
        return new DelegatingSeekableInputStream(new SeekByteArray(this.data)) {
          @Override
          public void seek(long newPos) {
            ((SeekByteArray) this.getStream()).setPos((int) newPos);
          }
  
          @Override
          public long getPos() {
            return ((SeekByteArray) this.getStream()).getPos();
          }
        };
      }
    }
  }
  