这是indexloc提供的服务，不要输入任何密码
Skip to content

[BAEL-8051-serialize-enum-value-in-avro] - article code #18479

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Apr 25, 2025
Merged

[BAEL-8051-serialize-enum-value-in-avro] - article code #18479

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
179 changes: 179 additions & 0 deletions ...-libraries-3/src/test/java/com/baeldung/apache/avro/SerializeEnumValueInAvroUnitTest.java
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,179 @@
package com.baeldung.apache.avro;

import org.apache.avro.Schema;
import org.apache.avro.SchemaBuilder;
import org.apache.avro.file.DataFileReader;
import org.apache.avro.file.DataFileWriter;
import org.apache.avro.generic.GenericData;
import org.apache.avro.generic.GenericDatumReader;
import org.apache.avro.generic.GenericDatumWriter;
import org.apache.avro.generic.GenericRecord;
import org.apache.avro.io.DatumReader;
import org.apache.avro.io.DatumWriter;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.io.TempDir;

import java.io.File;
import java.io.IOException;
import java.nio.file.Path;

import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
import static org.junit.jupiter.api.Assertions.assertEquals;

public class SerializeEnumValueInAvroUnitTest {

@TempDir
Path tempDir;

private Schema colorEnum;
private Schema recordSchema;
private Schema unionSchema;
private Schema recordWithUnionSchema;

@BeforeEach
void setUp() {
// Create enum schema
colorEnum = SchemaBuilder.enumeration("Color")
.namespace("com.baeldung.apache.avro")
.symbols("UNKNOWN", "GREEN", "RED", "BLUE");

// Create record schema with enum field
recordSchema = SchemaBuilder.record("ColorRecord")
.namespace("com.baeldung.apache.avro")
.fields()
.name("color")
.type(colorEnum)
.noDefault()
.endRecord();

// Create union schema with enum and null
unionSchema = SchemaBuilder.unionOf()
.type(colorEnum)
.and()
.nullType()
.endUnion();

// Create record schema with union field
recordWithUnionSchema = SchemaBuilder.record("ColorRecordWithUnion")
.namespace("com.baeldung.apache.avro")
.fields()
.name("color")
.type(unionSchema)
.noDefault()
.endRecord();
}

@Test
void whenSerializingEnum_thenSuccess() throws IOException {
File file = tempDir.resolve("color.avro").toFile();

// Create record with enum value
GenericRecord record = new GenericData.Record(recordSchema);
GenericData.EnumSymbol colorSymbol = new GenericData.EnumSymbol(colorEnum, "RED");
record.put("color", colorSymbol);

// Write to file
DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(recordSchema);
try (DataFileWriter<GenericRecord> dataFileWriter = new DataFileWriter<>(datumWriter)) {
dataFileWriter.create(recordSchema, file);
dataFileWriter.append(record);
}

// Read from file
DatumReader<GenericRecord> datumReader = new GenericDatumReader<>(recordSchema);
try (DataFileReader<GenericRecord> dataFileReader = new DataFileReader<>(file, datumReader)) {
GenericRecord result = dataFileReader.next();
assertEquals("RED", result.get("color").toString());
}
}

@Test
void whenSerializingEnumInUnion_thenSuccess() throws IOException {
File file = tempDir.resolve("colorUnion.avro").toFile();

// Create record with enum in union
GenericRecord record = new GenericData.Record(recordWithUnionSchema);
GenericData.EnumSymbol colorSymbol = new GenericData.EnumSymbol(colorEnum, "GREEN");
record.put("color", colorSymbol);

// Write to file
DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(recordWithUnionSchema);
try (DataFileWriter<GenericRecord> dataFileWriter = new DataFileWriter<>(datumWriter)) {
dataFileWriter.create(recordWithUnionSchema, file);
dataFileWriter.append(record);
}

// Read from file
DatumReader<GenericRecord> datumReader = new GenericDatumReader<>(recordWithUnionSchema);
try (DataFileReader<GenericRecord> dataFileReader = new DataFileReader<>(file, datumReader)) {
GenericRecord result = dataFileReader.next();
assertEquals("GREEN", result.get("color").toString());
}
}

@Test
void whenSerializingNullInUnion_thenSuccess() throws IOException {
File file = tempDir.resolve("colorNull.avro").toFile();

// Create record with null in union
GenericRecord record = new GenericData.Record(recordWithUnionSchema);
record.put("color", null);

// Write to file
DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(recordWithUnionSchema);
assertDoesNotThrow(() -> {
try (DataFileWriter<GenericRecord> dataFileWriter = new DataFileWriter<>(datumWriter)) {
dataFileWriter.create(recordWithUnionSchema, file);
dataFileWriter.append(record);
}
});
}

@Test
void whenSchemaEvolution_thenDefaultValueUsed() throws IOException {
// Create schema with new enum value and default at schema level
String evolvedSchemaJson = "{\"type\":\"record\"," +
"\"name\":\"ColorRecord\"," +
"\"namespace\":\"com.baeldung.apache.avro\"," +
"\"fields\":[{\"name\":\"color\"," +
"\"type\":{\"type\":\"enum\"," +
"\"name\":\"Color\"," +
"\"symbols\":[\"UNKNOWN\",\"GREEN\",\"RED\",\"BLUE\",\"YELLOW\"]," +
"\"default\":\"UNKNOWN\"}}]}";

Schema evolvedRecordSchema = new Schema.Parser().parse(evolvedSchemaJson);
Schema evolvedEnum = evolvedRecordSchema.getField("color").schema();

File file = tempDir.resolve("colorEvolved.avro").toFile();

// Create record with new enum value
GenericRecord record = new GenericData.Record(evolvedRecordSchema);
GenericData.EnumSymbol colorSymbol = new GenericData.EnumSymbol(evolvedEnum, "YELLOW");
record.put("color", colorSymbol);

// Write with evolved schema
DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(evolvedRecordSchema);
try (DataFileWriter<GenericRecord> dataFileWriter = new DataFileWriter<>(datumWriter)) {
dataFileWriter.create(evolvedRecordSchema, file);
dataFileWriter.append(record);
}

// Create old schema without YELLOW but WITH default
String originalSchemaJson = "{\"type\":\"record\"," +
"\"name\":\"ColorRecord\"," +
"\"namespace\":\"com.baeldung.apache.avro\"," +
"\"fields\":[{\"name\":\"color\",\"type\":{\"type\":\"enum\",\"name\":\"Color\"," +
"\"symbols\":[\"UNKNOWN\",\"GREEN\",\"RED\",\"BLUE\"]," +
"\"default\":\"UNKNOWN\"}}]}";

Schema originalRecordSchema = new Schema.Parser().parse(originalSchemaJson);

// Read with original schema
DatumReader<GenericRecord> datumReader = new GenericDatumReader<>(evolvedRecordSchema, originalRecordSchema);
try (DataFileReader<GenericRecord> dataFileReader = new DataFileReader<>(file, datumReader)) {
GenericRecord result = dataFileReader.next();
assertEquals("UNKNOWN", result.get("color").toString());
}
}
}