How to use

getSchemaByID

method

in

com.linkedin.camus.schemaregistry.SchemaRegistry

 public MessageDecoderHelper invoke(String id) {
  this.schema = (this.registry.getSchemaByID(this.topicName, id));
  if (this.schema == null)
   throw new IllegalStateException("Unknown schema id: " + id);
  this.targetSchema = JSONToAvroMessageDecoder.this.latestSchema;
  return this;
 }
}

 public MessageDecoderHelper invoke() {
  buffer = getByteBuffer(payload);
  String id = Integer.toString(buffer.getInt());
  schema = registry.getSchemaByID(topicName, id);
  if (schema == null)
   throw new IllegalStateException("Unknown schema id: " + id);
  start = buffer.position() + buffer.arrayOffset();
  length = buffer.limit() - 5;
  // try to get a target schema, if any
  targetSchema = latestSchema;
  return this;
 }
}

private synchronized S fetchFromSchemaRegistry(String topic, String id) {
 try {
  S schema = registry.getSchemaByID(topic, id);
  return schema;
 } catch (SchemaNotFoundException e) {
  addFetchToFailureHistory(id);
  throw e;
 }
}

 @Test
 public void testMinInterval() throws InterruptedException {
  EasyMock.expect(registry.getSchemaByID(EasyMock.anyString(), EasyMock.anyString())).andThrow(
    new SchemaNotFoundException());
  EasyMock.expectLastCall().times(4);
  EasyMock.replay(registry);
  props.setProperty(GET_SCHEMA_BY_ID_MAX_RETIRES, String.valueOf(Integer.MAX_VALUE));
  props.setProperty(GET_SCHEMA_BY_ID_MIN_INTERVAL_SECONDS, "2");
  cachedRegistry = new CachedSchemaRegistry<Schema>(registry, props);
  for (int i = 0; i < 2; i++) {
   for (int j = 0; j < 5; j++) {
    try {
     cachedRegistry.getSchemaByID("dummyTopic", "dummyID");
    } catch (SchemaNotFoundException e) {
    }
    try {
     cachedRegistry.getSchemaByID("dummyTopic", "dummyID2");
    } catch (SchemaNotFoundException e) {
    }
   }
   Thread.sleep(2500);
  }
  EasyMock.verify(registry);
 }
}

@Test
public void testMaxRetries() {
 EasyMock.expect(registry.getSchemaByID(EasyMock.anyString(), EasyMock.anyString())).andThrow(
   new SchemaNotFoundException());
 EasyMock.expectLastCall().times(20);
 EasyMock.replay(registry);
 props.setProperty(GET_SCHEMA_BY_ID_MAX_RETIRES, "10");
 props.setProperty(GET_SCHEMA_BY_ID_MIN_INTERVAL_SECONDS, "0");
 cachedRegistry = new CachedSchemaRegistry<Schema>(registry, props);
 for (int i = 0; i < 100; i++) {
  try {
   cachedRegistry.getSchemaByID("dummyTopic", "dummyID");
  } catch (SchemaNotFoundException e) {
  }
  try {
   cachedRegistry.getSchemaByID("dummyTopic", "dummyID2");
  } catch (SchemaNotFoundException e) {
  }
 }
 EasyMock.verify(registry);
}

private synchronized S fetchFromSchemaRegistry(String topic, String id) {
 try {
  S schema = registry.getSchemaByID(topic, id);
  return schema;
 } catch (SchemaNotFoundException e) {
  addFetchToFailureHistory(id);
  throw e;
 }
}

@Test
public void testWithSchema() {
  SchemaRegistry schemaRegistry = createMock(SchemaRegistry.class);
  Schema schema = SchemaBuilder.record("testRecord").namespace("my.name.space")
      .fields().name("field").type().stringType().noDefault().endRecord();
  expect(schemaRegistry.getSchemaByID("myTopic", "1751217253")).andReturn(schema);
  replay(schemaRegistry);
  KafkaAvroMessageDecoder kafkaAvroMessageDecoder = new KafkaAvroMessageDecoder();
  final byte[] bytes = "whatever".getBytes();
  bytes[0] = 0x0; // Magic byte
  KafkaAvroMessageDecoder.MessageDecoderHelper messageDecoderHelper = kafkaAvroMessageDecoder.new MessageDecoderHelper(schemaRegistry, "myTopic", bytes);
  KafkaAvroMessageDecoder.MessageDecoderHelper actualResult = messageDecoderHelper.invoke();
  verify(schemaRegistry);
  assertEquals("my.name.space", actualResult.getSchema().getNamespace());
  assertEquals(5, actualResult.getStart());
  assertEquals(bytes, actualResult.getBuffer().array());
  assertEquals(3, actualResult.getLength());
}

 registry.getSchemaByID("test", "abc");
 fail("Should have failed with a SchemaNotFoundException.");
} catch (SchemaNotFoundException e) {
 registry.getSchemaByID("test", "abc");
 fail("Should have failed with a SchemaNotFoundException.");
} catch (SchemaNotFoundException e) {
assertEquals(getSchema1(), registry.getSchemaByID("test", id));
assertEquals(new SchemaDetails("test", id, getSchema1()), registry.getLatestSchemaByTopic("test"));
assertEquals(getSchema1(), registry.getSchemaByID("test", id));
assertEquals(getSchema2(), registry.getSchemaByID("test", secondId));
assertEquals(new SchemaDetails("test", secondId, getSchema2()), registry.getLatestSchemaByTopic("test"));
 registry.getSchemaByID("test-2", "");
 fail("Should have failed with a SchemaNotFoundException.");
} catch (SchemaNotFoundException e) {
assertEquals(getSchema1(), registry.getSchemaByID("test", id));
assertEquals(getSchema2(), registry.getSchemaByID("test", secondId));
assertEquals(new SchemaDetails("test", secondId, getSchema2()), registry.getLatestSchemaByTopic("test"));