patricklucas opened a new issue #9718: URL: https://github.com/apache/pulsar/issues/9718
**Describe the bug** If you have an Avro "fixed" field in a record (or presumably if you try to produce a "fixed" field directly), you get a ClassCastException when producing a message. ``` java.lang.ClassCastException: class org.apache.pulsar.examples.Fixed cannot be cast to class org.apache.pulsar.shade.org.apache.avro.generic.GenericFixed (org.apache.pulsar.examples.Fixed and org.apache.pulsar.shade.org.apache.avro.generic.GenericFixed are in unnamed module of loader 'app') ``` (full traceback below) I slightly tweaked @sijie 's [`pulsar-avro-schema-example`](https://github.com/sijie/pulsar-avro-schema-example) project to demonstrate the issue: [patricklucas/pulsar-avro-schema-example](https://github.com/patricklucas/pulsar-avro-schema-example). (I updated dependencies, and then added a [fixed field](https://github.com/patricklucas/pulsar-avro-schema-example/blob/master/src/main/avro/fixed.avsc) to the [TwitterSchema](https://github.com/patricklucas/pulsar-avro-schema-example/blob/master/src/main/avro/twitter.avsc) record. Additionally, I added code to serialize the message to JSON before producing, to demonstrate that Avro itself handles the message correctly) It's possible this is unsupported in some way by Pulsar, but I couldn't find anything in the documentation about such limitations, so I thought I'd ask here. **To Reproduce** Steps to reproduce the behavior: 1. Clone the project [patricklucas/pulsar-avro-schema-example](https://github.com/patricklucas/pulsar-avro-schema-example) 2. Run [TweetProducer](https://github.com/patricklucas/pulsar-avro-schema-example/blob/master/src/main/java/org/apache/pulsar/examples/TweetProducer.java), passing a Pulsar service URL as a single argument 3. Observe error **Expected behavior** The message should be serialized successfully. **Additional context** Full traceback: ``` org.apache.pulsar.client.api.SchemaSerializationException: java.lang.ClassCastException: class org.apache.pulsar.examples.Fixed cannot be cast to class org.apache.pulsar.shade.org.apache.avro.generic.GenericFixed (org.apache.pulsar.examples.Fixed and org.apache.pulsar.shade.org.apache.avro.generic.GenericFixed are in unnamed module of loader 'app') at org.apache.pulsar.client.impl.schema.writer.AvroWriter.write(AvroWriter.java:55) at org.apache.pulsar.client.impl.schema.AbstractStructSchema.encode(AbstractStructSchema.java:50) at org.apache.pulsar.client.impl.TypedMessageBuilderImpl.value(TypedMessageBuilderImpl.java:178) at org.apache.pulsar.client.impl.ProducerBase.send(ProducerBase.java:63) at org.apache.pulsar.examples.TweetProducer.main(TweetProducer.java:43) Caused by: java.lang.ClassCastException: class org.apache.pulsar.examples.Fixed cannot be cast to class org.apache.pulsar.shade.org.apache.avro.generic.GenericFixed (org.apache.pulsar.examples.Fixed and org.apache.pulsar.shade.org.apache.avro.generic.GenericFixed are in unnamed module of loader 'app') at org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumWriter.writeFixed(GenericDatumWriter.java:339) at org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumWriter.writeWithoutConversion(GenericDatumWriter.java:147) at org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumWriter.write(GenericDatumWriter.java:82) at org.apache.pulsar.shade.org.apache.avro.reflect.ReflectDatumWriter.write(ReflectDatumWriter.java:158) at org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumWriter.writeField(GenericDatumWriter.java:206) at org.apache.pulsar.shade.org.apache.avro.specific.SpecificDatumWriter.writeField(SpecificDatumWriter.java:101) at org.apache.pulsar.shade.org.apache.avro.reflect.ReflectDatumWriter.writeField(ReflectDatumWriter.java:186) at org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumWriter.writeRecord(GenericDatumWriter.java:195) at org.apache.pulsar.shade.org.apache.avro.specific.SpecificDatumWriter.writeRecord(SpecificDatumWriter.java:83) at org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumWriter.writeWithoutConversion(GenericDatumWriter.java:130) at org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumWriter.write(GenericDatumWriter.java:82) at org.apache.pulsar.shade.org.apache.avro.reflect.ReflectDatumWriter.write(ReflectDatumWriter.java:158) at org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumWriter.write(GenericDatumWriter.java:72) at org.apache.pulsar.client.impl.schema.writer.AvroWriter.write(AvroWriter.java:53) ... 4 more ``` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
