[
https://issues.apache.org/jira/browse/KAFKA-5891?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16167493#comment-16167493
]
Artem Plotnikov commented on KAFKA-5891:
----------------------------------------
Seems like Kafka Connect's Cast transformation loses schema information
(basically, schema name) while doing type casting. I was able to reproduce this
problem with the following test in org.apache.kafka.connect.transforms.CastTest
for current trunk repository branch:
{code}
@SuppressWarnings("unchecked")
@Test
public void castWholeRecordValueWithSchemaBooleanAndTimestampField() {
final Cast<SourceRecord> xform = new Cast.Value<>();
xform.configure(Collections.singletonMap(Cast.SPEC_CONFIG,
"int64:boolean"));
SchemaBuilder builder = SchemaBuilder.struct();
builder.field("int64", Schema.INT64_SCHEMA);
builder.field("timestamp", Timestamp.SCHEMA);
Schema supportedTypesSchema = builder.build();
Struct recordValue = new Struct(supportedTypesSchema);
recordValue.put("int64", (long) 64);
recordValue.put("timestamp", new java.sql.Timestamp(0L));
SourceRecord transformed = xform.apply(new SourceRecord(null, null,
"topic", 0,
supportedTypesSchema, recordValue));
assertEquals(true, ((Struct) transformed.value()).get("int64"));
assertEquals(new java.sql.Timestamp(0L), ((Struct)
transformed.value()).get("timestamp"));
}
{code}
The problem is that Timestamp.SCHEMA has schema.type = 'INT64' and schema.name
= "org.apache.kafka.connect.data.Timestamp", but
org.apache.kafka.connect.transforms.Cast#getOrBuildSchema method copies
schema.type only:
{code}
SchemaBuilder fieldBuilder =
convertFieldType(casts.containsKey(field.name()) ? casts.get(field.name())
: field.schema().type());
{code}
> Cast transformation fails if record schema contains timestamp field
> -------------------------------------------------------------------
>
> Key: KAFKA-5891
> URL: https://issues.apache.org/jira/browse/KAFKA-5891
> Project: Kafka
> Issue Type: Bug
> Components: KafkaConnect
> Affects Versions: 0.11.0.0
> Reporter: Artem Plotnikov
>
> I have the following simple type cast transformation:
> {code}
> name=postgresql-source-simple
> connector.class=io.confluent.connect.jdbc.JdbcSourceConnector
> tasks.max=1
> connection.url=jdbc:postgresql://localhost:5432/testdb?user=postgres&password=mysecretpassword
> query=SELECT 1::INT as a, '2017-09-14 10:23:54'::TIMESTAMP as b
> transforms=Cast
> transforms.Cast.type=org.apache.kafka.connect.transforms.Cast$Value
> transforms.Cast.spec=a:boolean
> mode=bulk
> topic.prefix=clients
> {code}
> Which fails with the following exception in runtime:
> {code}
> [2017-09-14 16:51:01,885] ERROR Task postgresql-source-simple-0 threw an
> uncaught and unrecoverable exception
> (org.apache.kafka.connect.runtime.WorkerTask:148)
> org.apache.kafka.connect.errors.DataException: Invalid Java object for schema
> type INT64: class java.sql.Timestamp for field: "null"
> at
> org.apache.kafka.connect.data.ConnectSchema.validateValue(ConnectSchema.java:239)
> at
> org.apache.kafka.connect.data.ConnectSchema.validateValue(ConnectSchema.java:209)
> at org.apache.kafka.connect.data.Struct.put(Struct.java:214)
> at
> org.apache.kafka.connect.transforms.Cast.applyWithSchema(Cast.java:152)
> at org.apache.kafka.connect.transforms.Cast.apply(Cast.java:108)
> at
> org.apache.kafka.connect.runtime.TransformationChain.apply(TransformationChain.java:38)
> at
> org.apache.kafka.connect.runtime.WorkerSourceTask.sendRecords(WorkerSourceTask.java:190)
> at
> org.apache.kafka.connect.runtime.WorkerSourceTask.execute(WorkerSourceTask.java:168)
> at
> org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:146)
> at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:190)
> at
> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
> at java.util.concurrent.FutureTask.run(FutureTask.java:266)
> at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> at java.lang.Thread.run(Thread.java:745)
> {code}
> If I remove the transforms.* part of the connector it will work correctly.
> Actually, it doesn't really matter which types I use in the transformation
> for field 'a', just the existence of a timestamp field brings the exception.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
