TestJSONFile.java

/*
 * 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.arrow.vector.ipc;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertNull;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import org.apache.arrow.memory.BufferAllocator;
import org.apache.arrow.vector.FieldVector;
import org.apache.arrow.vector.VectorSchemaRoot;
import org.apache.arrow.vector.complex.StructVector;
import org.apache.arrow.vector.complex.impl.ComplexWriterImpl;
import org.apache.arrow.vector.complex.writer.BaseWriter;
import org.apache.arrow.vector.dictionary.DictionaryProvider;
import org.apache.arrow.vector.dictionary.DictionaryProvider.MapDictionaryProvider;
import org.apache.arrow.vector.types.UnionMode;
import org.apache.arrow.vector.types.pojo.ArrowType;
import org.apache.arrow.vector.types.pojo.Field;
import org.apache.arrow.vector.types.pojo.FieldType;
import org.apache.arrow.vector.types.pojo.Schema;
import org.apache.arrow.vector.util.Validator;
import org.junit.jupiter.api.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class TestJSONFile extends BaseFileTest {
  private static final Logger LOGGER = LoggerFactory.getLogger(TestJSONFile.class);

  @Test
  public void testNoBatches() throws IOException {
    File file = new File("target/no_batches.json");

    try (BufferAllocator originalVectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        StructVector parent = StructVector.empty("parent", originalVectorAllocator)) {
      BaseWriter.ComplexWriter writer = new ComplexWriterImpl("root", parent);
      BaseWriter.StructWriter rootWriter = writer.rootAsStruct();
      rootWriter.integer("int");
      rootWriter.uInt1("uint1");
      rootWriter.bigInt("bigInt");
      rootWriter.float4("float");
      JsonFileWriter jsonWriter = new JsonFileWriter(file, JsonFileWriter.config().pretty(true));
      jsonWriter.start(new VectorSchemaRoot(parent.getChild("root")).getSchema(), null);
      jsonWriter.close();
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);
    }
  }

  @Test
  public void testWriteRead() throws IOException {
    File file = new File("target/mytest.json");
    int count = COUNT;

    // write
    try (BufferAllocator originalVectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        StructVector parent = StructVector.empty("parent", originalVectorAllocator)) {
      writeData(count, parent);
      writeJSON(file, new VectorSchemaRoot(parent.getChild("root")), null);
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateContent(count, root);
      }
    }
  }

  @Test
  public void testWriteReadComplexJSON() throws IOException {
    File file = new File("target/mytest_complex.json");
    int count = COUNT;

    // write
    try (BufferAllocator originalVectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        StructVector parent = StructVector.empty("parent", originalVectorAllocator)) {
      writeComplexData(count, parent);
      writeJSON(file, new VectorSchemaRoot(parent.getChild("root")), null);
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator); ) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateComplexContent(count, root);
      }
    }
  }

  @Test
  public void testWriteComplexJSON() throws IOException {
    File file = new File("target/mytest_write_complex.json");
    int count = COUNT;
    try (BufferAllocator vectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        StructVector parent = StructVector.empty("parent", vectorAllocator)) {
      writeComplexData(count, parent);
      VectorSchemaRoot root = new VectorSchemaRoot(parent.getChild("root"));
      validateComplexContent(root.getRowCount(), root);
      writeJSON(file, root, null);
    }
  }

  public void writeJSON(File file, VectorSchemaRoot root, DictionaryProvider provider)
      throws IOException {
    JsonFileWriter writer = new JsonFileWriter(file, JsonFileWriter.config().pretty(true));
    writer.start(root.getSchema(), provider);
    writer.write(root);
    writer.close();
  }

  @Test
  public void testWriteReadUnionJSON() throws IOException {
    File file = new File("target/mytest_write_union.json");
    int count = COUNT;
    try (BufferAllocator vectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        StructVector parent = StructVector.empty("parent", vectorAllocator)) {
      writeUnionData(count, parent);
      printVectors(parent.getChildrenFromFields());

      try (VectorSchemaRoot root = new VectorSchemaRoot(parent.getChild("root"))) {
        validateUnionData(count, root);
        writeJSON(file, root, null);

        // read
        try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE)) {
          JsonFileReader reader = new JsonFileReader(file, readerAllocator);

          Schema schema = reader.start();
          LOGGER.debug("reading schema: " + schema);

          try (VectorSchemaRoot rootFromJson = reader.read(); ) {
            validateUnionData(count, rootFromJson);
            Validator.compareVectorSchemaRoot(root, rootFromJson);
          }
        }
      }
    }
  }

  @Test
  public void testWriteReadDateTimeJSON() throws IOException {
    File file = new File("target/mytest_datetime.json");
    int count = COUNT;

    // write
    try (BufferAllocator vectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        StructVector parent = StructVector.empty("parent", vectorAllocator)) {

      writeDateTimeData(count, parent);

      printVectors(parent.getChildrenFromFields());

      VectorSchemaRoot root = new VectorSchemaRoot(parent.getChild("root"));
      validateDateTimeContent(count, root);

      writeJSON(file, new VectorSchemaRoot(parent.getChild("root")), null);
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateDateTimeContent(count, root);
      }
    }
  }

  @Test
  public void testWriteReadDictionaryJSON() throws IOException {
    File file = new File("target/mytest_dictionary.json");

    // write
    try (BufferAllocator vectorAllocator =
        allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE)) {
      MapDictionaryProvider provider = new MapDictionaryProvider();

      try (VectorSchemaRoot root = writeFlatDictionaryData(vectorAllocator, provider)) {
        printVectors(root.getFieldVectors());
        validateFlatDictionary(root, provider);
        writeJSON(file, root, provider);
      }

      // Need to close dictionary vectors
      for (long id : provider.getDictionaryIds()) {
        provider.lookup(id).getVector().close();
      }
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateFlatDictionary(root, reader);
      }
    }
  }

  @Test
  public void testWriteReadNestedDictionaryJSON() throws IOException {
    File file = new File("target/mytest_dict_nested.json");

    // data being written:
    // [['foo', 'bar'], ['foo'], ['bar']] -> [[0, 1], [0], [1]]

    // write
    try (BufferAllocator vectorAllocator =
        allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE)) {
      MapDictionaryProvider provider = new MapDictionaryProvider();

      try (VectorSchemaRoot root = writeNestedDictionaryData(vectorAllocator, provider)) {
        printVectors(root.getFieldVectors());
        validateNestedDictionary(root, provider);
        writeJSON(file, root, provider);
      }

      // Need to close dictionary vectors
      for (long id : provider.getDictionaryIds()) {
        provider.lookup(id).getVector().close();
      }
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateNestedDictionary(root, reader);
      }
    }
  }

  @Test
  public void testWriteReadDecimalJSON() throws IOException {
    File file = new File("target/mytest_decimal.json");

    // write
    try (BufferAllocator vectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        VectorSchemaRoot root = writeDecimalData(vectorAllocator)) {
      printVectors(root.getFieldVectors());
      validateDecimalData(root);
      writeJSON(file, root, null);
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateDecimalData(root);
      }
    }
  }

  @Test
  public void testSetStructLength() throws IOException {
    File file = new File("../../docs/source/format/integration_json_examples/struct.json");
    if (!file.exists()) {
      file = new File("../docs/source/format/integration_json_examples/struct.json");
    }
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        FieldVector vector = root.getVector("struct_nullable");
        assertEquals(7, vector.getValueCount());
      }
    }
  }

  @Test
  public void testWriteReadVarBinJSON() throws IOException {
    File file = new File("target/mytest_varbin.json");
    int count = COUNT;

    // write
    try (BufferAllocator vectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        StructVector parent = StructVector.empty("parent", vectorAllocator)) {
      writeVarBinaryData(count, parent);
      VectorSchemaRoot root = new VectorSchemaRoot(parent.getChild("root"));
      validateVarBinary(count, root);
      writeJSON(file, new VectorSchemaRoot(parent.getChild("root")), null);
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateVarBinary(count, root);
      }
    }
  }

  @Test
  public void testWriteReadMapJSON() throws IOException {
    File file = new File("target/mytest_map.json");

    // write
    try (BufferAllocator vectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        VectorSchemaRoot root = writeMapData(vectorAllocator)) {
      printVectors(root.getFieldVectors());
      validateMapData(root);
      writeJSON(file, root, null);
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {
      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateMapData(root);
      }
    }
  }

  @Test
  public void testWriteReadNullJSON() throws IOException {
    File file = new File("target/mytest_null.json");
    int valueCount = 10;

    // write
    try (BufferAllocator vectorAllocator =
            allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
        VectorSchemaRoot root = writeNullData(valueCount)) {
      printVectors(root.getFieldVectors());
      validateNullData(root, valueCount);
      writeJSON(file, root, null);
    }

    // read
    try (BufferAllocator readerAllocator =
            allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
        JsonFileReader reader = new JsonFileReader(file, readerAllocator)) {

      Schema schema = reader.start();
      LOGGER.debug("reading schema: " + schema);

      // initialize vectors
      try (VectorSchemaRoot root = reader.read(); ) {
        validateNullData(root, valueCount);
      }
    }
  }

  /** Regression test for ARROW-17107. */
  @Test
  public void testRoundtripEmptyVector() throws Exception {
    final List<Field> fields =
        Arrays.asList(
            Field.nullable("utf8", ArrowType.Utf8.INSTANCE),
            Field.nullable("largeutf8", ArrowType.LargeUtf8.INSTANCE),
            Field.nullable("binary", ArrowType.Binary.INSTANCE),
            Field.nullable("largebinary", ArrowType.LargeBinary.INSTANCE),
            Field.nullable("fixedsizebinary", new ArrowType.FixedSizeBinary(2)),
            Field.nullable("decimal128", new ArrowType.Decimal(3, 2, 128)),
            Field.nullable("decimal128", new ArrowType.Decimal(3, 2, 256)),
            new Field(
                "list",
                FieldType.nullable(ArrowType.List.INSTANCE),
                Collections.singletonList(Field.nullable("items", new ArrowType.Int(32, true)))),
            new Field(
                "largelist",
                FieldType.nullable(ArrowType.LargeList.INSTANCE),
                Collections.singletonList(Field.nullable("items", new ArrowType.Int(32, true)))),
            new Field(
                "map",
                FieldType.nullable(new ArrowType.Map(/*keyssorted*/ false)),
                Collections.singletonList(
                    new Field(
                        "items",
                        FieldType.notNullable(ArrowType.Struct.INSTANCE),
                        Arrays.asList(
                            Field.notNullable("keys", new ArrowType.Int(32, true)),
                            Field.nullable("values", new ArrowType.Int(32, true)))))),
            new Field(
                "fixedsizelist",
                FieldType.nullable(new ArrowType.FixedSizeList(2)),
                Collections.singletonList(Field.nullable("items", new ArrowType.Int(32, true)))),
            new Field(
                "denseunion",
                FieldType.nullable(new ArrowType.Union(UnionMode.Dense, new int[] {0})),
                Collections.singletonList(Field.nullable("items", new ArrowType.Int(32, true)))),
            new Field(
                "sparseunion",
                FieldType.nullable(new ArrowType.Union(UnionMode.Sparse, new int[] {0})),
                Collections.singletonList(Field.nullable("items", new ArrowType.Int(32, true)))));

    for (final Field field : fields) {
      final Schema schema = new Schema(Collections.singletonList(field));
      try (final VectorSchemaRoot root = VectorSchemaRoot.create(schema, allocator)) {
        Path outputPath = Files.createTempFile("arrow-", ".json");
        File outputFile = outputPath.toFile();
        outputFile.deleteOnExit();

        // Try with no allocation
        try (final JsonFileWriter jsonWriter =
            new JsonFileWriter(outputFile, JsonFileWriter.config().pretty(true))) {
          jsonWriter.start(schema, null);
          jsonWriter.write(root);
        } catch (Exception e) {
          throw new RuntimeException("Test failed for empty vector of type " + field, e);
        }

        try (JsonFileReader reader = new JsonFileReader(outputFile, allocator)) {
          final Schema readSchema = reader.start();
          assertEquals(schema, readSchema);
          try (final VectorSchemaRoot data = reader.read()) {
            assertNotNull(data);
            assertEquals(0, data.getRowCount());
          }
          assertNull(reader.read());
        }

        // Try with an explicit allocation
        root.allocateNew();
        root.setRowCount(0);
        try (final JsonFileWriter jsonWriter =
            new JsonFileWriter(outputFile, JsonFileWriter.config().pretty(true))) {
          jsonWriter.start(schema, null);
          jsonWriter.write(root);
        } catch (Exception e) {
          throw new RuntimeException("Test failed for empty vector of type " + field, e);
        }

        try (JsonFileReader reader = new JsonFileReader(outputFile, allocator)) {
          final Schema readSchema = reader.start();
          assertEquals(schema, readSchema);
          try (final VectorSchemaRoot data = reader.read()) {
            assertNotNull(data);
            assertEquals(0, data.getRowCount());
          }
          assertNull(reader.read());
        }
      }
    }
  }
}