GH-3149: Enable ParquetAvroReader to handle decimal types for int32/64

parquet-avro/src/main/java/org/apache/parquet/avro/AvroConverters.java

@@ -20,6 +20,8 @@
 
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
+import java.math.BigDecimal;
+import java.math.BigInteger;
 import java.nio.ByteBuffer;
 import org.apache.avro.Schema;
 import org.apache.avro.generic.GenericData;
@@ -29,6 +31,7 @@
 import org.apache.parquet.io.api.Binary;
 import org.apache.parquet.io.api.GroupConverter;
 import org.apache.parquet.io.api.PrimitiveConverter;
+import org.apache.parquet.schema.LogicalTypeAnnotation;
 import org.apache.parquet.schema.PrimitiveStringifier;
 import org.apache.parquet.schema.PrimitiveType;
 
@@ -339,4 +342,36 @@ public String convert(Binary binary) {
       return stringifier.stringify(binary);
     }
   }
+
+  static final class FieldDecimalIntConverter extends AvroPrimitiveConverter {
+    private final int scale;
+
+    public FieldDecimalIntConverter(ParentValueContainer parent, PrimitiveType type) {
+      super(parent);
+      LogicalTypeAnnotation.DecimalLogicalTypeAnnotation decimalType =
+          (LogicalTypeAnnotation.DecimalLogicalTypeAnnotation) type.getLogicalTypeAnnotation();
+      this.scale = decimalType.getScale();
+    }
+
+    @Override
+    public void addInt(int value) {
+      parent.add(new BigDecimal(BigInteger.valueOf(value), scale));
+    }
+  }
+
+  static final class FieldDecimalLongConverter extends AvroPrimitiveConverter {
+    private final int scale;
+
+    public FieldDecimalLongConverter(ParentValueContainer parent, PrimitiveType type) {
+      super(parent);
+      LogicalTypeAnnotation.DecimalLogicalTypeAnnotation decimalType =
+          (LogicalTypeAnnotation.DecimalLogicalTypeAnnotation) type.getLogicalTypeAnnotation();
+      this.scale = decimalType.getScale();
+    }
+
+    @Override
+    public void addLong(long value) {
+      parent.add(new BigDecimal(BigInteger.valueOf(value), scale));
+    }
+  }
 }

parquet-avro/src/main/java/org/apache/parquet/avro/AvroRecordConverter.java

@@ -337,6 +337,14 @@ private static Converter newConverter(
     return newConverter(schema, type, model, null, setter, validator);
   }
 
+  private static boolean isDecimalType(Type type) {
+    if (!type.isPrimitive()) {
+      return false;
+    }
+    LogicalTypeAnnotation annotation = type.getLogicalTypeAnnotation();
+    return annotation instanceof LogicalTypeAnnotation.DecimalLogicalTypeAnnotation;
+  }
+
   private static Converter newConverter(
       Schema schema,
       Type type,
@@ -359,6 +367,9 @@ private static Converter newConverter(
       case BOOLEAN:
         return new AvroConverters.FieldBooleanConverter(parent);
       case INT:
+        if (isDecimalType(type)) {
+          return new AvroConverters.FieldDecimalIntConverter(parent, type.asPrimitiveType());
+        }
         Class<?> intDatumClass = getDatumClass(conversion, knownClass, schema, model);
         if (intDatumClass == null) {
           return new AvroConverters.FieldIntegerConverter(parent);
@@ -374,6 +385,9 @@ private static Converter newConverter(
         }
         return new AvroConverters.FieldIntegerConverter(parent);
       case LONG:
+        if (isDecimalType(type)) {
+          return new AvroConverters.FieldDecimalLongConverter(parent, type.asPrimitiveType());
+        }
         return new AvroConverters.FieldLongConverter(parent);
       case FLOAT:
         return new AvroConverters.FieldFloatConverter(parent);

parquet-avro/src/test/java/org/apache/parquet/avro/TestReadWrite.java

@@ -19,6 +19,9 @@
 package org.apache.parquet.avro;
 
 import static org.apache.parquet.avro.AvroTestUtil.optional;
+import static org.apache.parquet.schema.PrimitiveType.PrimitiveTypeName.INT32;
+import static org.apache.parquet.schema.PrimitiveType.PrimitiveTypeName.INT64;
+import static org.apache.parquet.schema.Type.Repetition.REQUIRED;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 
@@ -61,17 +64,23 @@
 import org.apache.parquet.conf.ParquetConfiguration;
 import org.apache.parquet.conf.PlainParquetConfiguration;
 import org.apache.parquet.example.data.Group;
+import org.apache.parquet.example.data.GroupFactory;
+import org.apache.parquet.example.data.simple.SimpleGroupFactory;
 import org.apache.parquet.hadoop.ParquetReader;
 import org.apache.parquet.hadoop.ParquetWriter;
 import org.apache.parquet.hadoop.api.WriteSupport;
+import org.apache.parquet.hadoop.example.ExampleParquetWriter;
 import org.apache.parquet.hadoop.example.GroupReadSupport;
 import org.apache.parquet.hadoop.util.HadoopCodecs;
 import org.apache.parquet.io.InputFile;
 import org.apache.parquet.io.LocalInputFile;
 import org.apache.parquet.io.LocalOutputFile;
 import org.apache.parquet.io.api.Binary;
 import org.apache.parquet.io.api.RecordConsumer;
+import org.apache.parquet.schema.LogicalTypeAnnotation;
+import org.apache.parquet.schema.MessageType;
 import org.apache.parquet.schema.MessageTypeParser;
+import org.apache.parquet.schema.PrimitiveType;
 import org.junit.Assert;
 import org.junit.Rule;
 import org.junit.Test;
@@ -400,6 +409,68 @@ public void testFixedDecimalValues() throws Exception {
     Assert.assertEquals("Content should match", expected, records);
   }
 
+  @Test
+  public void testDecimalIntegerValues() throws Exception {
+
+    File file = temp.newFile("test_decimal_integer_values.parquet");
+    file.delete();
+    Path path = new Path(file.toString());
+
+    MessageType parquetSchema = new MessageType(
+        "test_decimal_integer_values",
+        new PrimitiveType(REQUIRED, INT32, "decimal_age")
+            .withLogicalTypeAnnotation(LogicalTypeAnnotation.decimalType(2, 5)),
+        new PrimitiveType(REQUIRED, INT64, "decimal_salary")
+            .withLogicalTypeAnnotation(LogicalTypeAnnotation.decimalType(1, 10)));
+
+    try (ParquetWriter<Group> writer =
+        ExampleParquetWriter.builder(path).withType(parquetSchema).build()) {
+
+      GroupFactory factory = new SimpleGroupFactory(parquetSchema);
+
+      Group group1 = factory.newGroup();
+      group1.add("decimal_age", 2534);
+      group1.add("decimal_salary", 234L);
+      writer.write(group1);
+
+      Group group2 = factory.newGroup();
+      group2.add("decimal_age", 4267);
+      group2.add("decimal_salary", 1203L);
+      writer.write(group2);
+    }
+
+    GenericData decimalSupport = new GenericData();
+    decimalSupport.addLogicalTypeConversion(new Conversions.DecimalConversion());
+
+    List<GenericRecord> records = Lists.newArrayList();
+    try (ParquetReader<GenericRecord> reader = AvroParquetReader.<GenericRecord>builder(path)
+        .withDataModel(decimalSupport)
+        .build()) {
+      GenericRecord rec;
+      while ((rec = reader.read()) != null) {
+        records.add(rec);
+      }
+    }
+
+    Assert.assertEquals("Should read 2 records", 2, records.size());
+
+    // INT32 values
+    Object firstAge = records.get(0).get("decimal_age");
+    Object secondAge = records.get(1).get("decimal_age");
+
+    Assert.assertTrue("Should be BigDecimal, but is " + firstAge.getClass(), firstAge instanceof BigDecimal);
+    Assert.assertEquals("Should be 25.34, but is " + firstAge, new BigDecimal("25.34"), firstAge);
+    Assert.assertEquals("Should be 42.67, but is " + secondAge, new BigDecimal("42.67"), secondAge);
+
+    // INT64 values
+    Object firstSalary = records.get(0).get("decimal_salary");
+    Object secondSalary = records.get(1).get("decimal_salary");
+
+    Assert.assertTrue("Should be BigDecimal, but is " + firstSalary.getClass(), firstSalary instanceof BigDecimal);
+    Assert.assertEquals("Should be 23.4, but is " + firstSalary, new BigDecimal("23.4"), firstSalary);
+    Assert.assertEquals("Should be 120.3, but is " + secondSalary, new BigDecimal("120.3"), secondSalary);
+  }
+
   @Test
   public void testAll() throws Exception {
     Schema schema =