"Failed to discover artifact type from content." for /apis/ccompat/v7/schemas/ids/ID call

[simonepm]

On Apicurio Registry v3.6.0 we register proto artifacts in the format <topic_name>-value using v2 API using null as group id.

Correctly we can see the schema registered in v7 ccompat:

/apis/ccompat/v7/subjects/<topic_name>-value/versions/version

The endpoint returns a subject with a certain ID

But, when looking for the schema by ID:

/apis/ccompat/v7/schemas/ids/ID

We receive:

{
    "message": "Failed to discover artifact type from content.",
    "error_code": 0
}

This is the same error returned when using io.confluent.kafka.serializers.protobuf.KafkaProtobufDeserializer causing the failure of our proto deserializations.

Is there a way to make /apis/ccompat/v7/schemas/ids/ID endpoint responding? In Apicurio 2 registry image this call works correctly, seems just a regression in Apicurio 3 registry image.

io/confluent/kafka/schemaregistry/client/rest/RestService.java

[apicurio-bot]

Thank you for reporting an issue!

Pinging @carlesarnal to respond or triage.