Invalid SchemaException for UUID while using AvroParquetWriter

Hi,

I am getting org.apache.parquet.schema.InvalidSchemaException: Cannot write a schema with an empty group: optional group id {} while I include a UUID field on my POJO object. Without UUID everything worked fine. I have seen Parquet suports UUID as part of [#PR-71] on 2.4 release.
But I am getting InvalidSchemaException on UUID. Is there anything that I am missing or its a known issue?

**My setup details:**

**gradle dependency :**

dependencies

{ compile group: 'org.springframework.boot', name: 'spring-boot-starter' compile group: 'org.projectlombok', name: 'lombok', version: '1.16.6' compile group: 'com.amazonaws', name: 'aws-java-sdk-bundle', version: '1.11.271' compile group: 'org.apache.parquet', name: 'parquet-avro', version: '1.10.1' compile group: 'org.apache.hadoop', name: 'hadoop-common', version: '3.1.1' compile group: 'org.apache.hadoop', name: 'hadoop-aws', version: '3.1.1' compile group: 'org.apache.hadoop', name: 'hadoop-client', version: '3.1.1' compile group: 'joda-time', name: 'joda-time' compile group: 'com.fasterxml.jackson.core', name: 'jackson-databind', version: '2.6.5' compile group: 'com.fasterxml.jackson.datatype', name: 'jackson-datatype-joda', version: '2.6.5' }

**Model used:**

@Data
public class Employee

{ private UUID id; private String name; private int age; private Address address; }

@Data
public class Address

{ private String streetName; private String city; private Zip zip; }

@Data
public class Zip

{ private int zip; private int ext; }

 

**My Serializer Code:**

public void serialize(List inputDataToSerialize, CompressionCodecName compressionCodecName) throws IOException {

Path path = new Path("s3a://parquetpoc/data_"+compressionCodecName+".parquet");
Class clazz = inputDataToSerialize.get(0).getClass();

try (ParquetWriter writer = AvroParquetWriter.builder(path)
.withSchema(ReflectData.AllowNull.get().getSchema(clazz)) // generate nullable fields
.withDataModel(ReflectData.get())
.withConf(parquetConfiguration)
.withCompressionCodec(compressionCodecName)
.withWriteMode(OVERWRITE)
.withWriterVersion(ParquetProperties.WriterVersion.PARQUET_2_0)
.build()) {

for (D input : inputDataToSerialize)

{ writer.write(input); }

}
}

private List **getInputDataToSerialize**(){
Address address = new Address();
address.setStreetName("Murry Ridge Dr");
address.setCity("Murrysville");
Zip zip = new Zip();
zip.setZip(15668);
zip.setExt(1234);

address.setZip(zip);

List employees = new ArrayList<>();

IntStream.range(0, 100000).forEach(i->

{ Employee employee = new Employee(); // employee.setId(UUID.randomUUID()); employee.setAge(20); employee.setName("Test"+i); employee.setAddress(address); employees.add(employee); }

);
return employees;
}

_\*\*Where generic Type D is Employee_

**Reporter**: [Felix Kizhakkel Jose](https://issues.apache.org/jira/secure/ViewProfile.jspa?name=FelixKJose) / @FelixKJose

_{**Note**: *This issue was originally created as [PARQUET-1679](https://issues.apache.org/jira/browse/PARQUET-1679). Please see the [migration documentation](https://issues.apache.org/jira/browse/PARQUET-2502) for further details.*}

Reproduce the failure with the Employee, Address, and Zip models, including the UUID field, and the AvroParquetWriter.builder call using ReflectData.AllowNull.get().getSchema(clazz). Compare the generated schema with the working version that omits UUID. Done means identifying the UUID schema-generation problem and verifying the corrected behavior with a regression test or documented compatibility result.

Written by the indexing model from the issue text.