Schema-registry: avro-maven-plugin with stringType config causes 40403 Schema not found

[dkirrane]

SchemaRegistryClient.getId gets back a 40403 Schema not found.

The issue is that the avro-maven-plugin generated code adds a "avro.java.string":"String" property, so SR fails to find the matching Schema.
I think Schema Registry needs to ignore this property? Or have an option to do so?

Reproduce:

1. Register the following Schema with Schema Registry.
   I use mvn io.confluent:kafka-schema-registry-maven-plugin:5.4.0:register

{
  "type":"record",
  "name":"Artist",
  "namespace":"com.mycompany.avro",
  "fields":[
    {"name":"album","type":{"type":"string"}}
  ]
}

1. Generate PoJo for Schema using avro-maven-plugin with stringType config:

<plugin>
    <groupId>org.apache.avro</groupId>
    <artifactId>avro-maven-plugin</artifactId>
    <version>1.9.2</version>
    <executions>
        <execution>
            <phase>generate-sources</phase>
            <goals>
                <goal>schema</goal>
            </goals>
            <configuration>
                <sourceDirectory>${project.basedir}/src/main/avro</sourceDirectory>
                <stringType>String</stringType>
            </configuration>
        </execution>
    </executions>
</plugin>

ISSUE: Open the generated Artist Pojo. The SCHEMA$ field will contain a new avro.java.string property to the schema i.e.

{"name":"album","type":{"type":"string","avro.java.string":"String"}}

1. Create a Avro Producer & send an Artist record to a Topic.
   NOTE: Producer needs to set AbstractKafkaAvroSerDeConfig.AUTO_REGISTER_SCHEMAS=false

2. Producer will fail 40403 Schema not found

Caused by: io.confluent.kafka.schemaregistry.client.rest.exceptions.RestClientException: Schema not found; error code: 40403
    at io.confluent.kafka.schemaregistry.client.rest.RestService.sendHttpRequest(RestService.java:266)
    at io.confluent.kafka.schemaregistry.client.rest.RestService.httpRequest(RestService.java:322)
    at io.confluent.kafka.schemaregistry.client.rest.RestService.lookUpSubjectVersion(RestService.java:389)
    at io.confluent.kafka.schemaregistry.client.rest.RestService.lookUpSubjectVersion(RestService.java:377)
    at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.getIdFromRegistry(CachedSchemaRegistryClient.java:165)
    at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.getId(CachedSchemaRegistryClient.java:302)
    at io.confluent.kafka.serializers.AbstractKafkaAvroSerializer.serializeImpl(AbstractKafkaAvroSerializer.java:74)
    at io.confluent.kafka.serializers.KafkaAvroSerializer.serialize(KafkaAvroSerializer.java:53)
    at io.confluent.kafka.streams.serdes.avro.SpecificAvroSerializer.serialize(SpecificAvroSerializer.java:65)
    at io.confluent.kafka.streams.serdes.avro.SpecificAvroSerializer.serialize(SpecificAvroSerializer.java:38)
    at org.apache.kafka.common.serialization.Serializer.serialize(Serializer.java:62)
    at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:903)
    at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:865)
    at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:752)
    at com.mycompany.test.Producer.send(Producer.java:44)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:675)
    at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:125)
    at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:132)
    at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:124)
    at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:74)
    at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
    at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:104)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:62)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:43)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:35)
    at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
    at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:202)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:198)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:135)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:69)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:229)
    at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:197)
    at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:211)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:191)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
    at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:69)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

[Kabowyad]

Hi, @dkirrane there's already same question, where you can find solution
https://github.com/confluentinc/schema-registry/issues/868

[idkw]

Had the same issue. My workaround is just to replace all the occurrences of the avro property then the schema hashcode properly matches with the original :

String cleanSchemaJson = MyGenearatedClass.getClassSchema()
            .toString()
            // workaround for issue https://github.com/confluentinc/schema-registry/issues/1352
            // caused by https://issues.apache.org/jira/browse/AVRO-803
            .replaceAll(Pattern.quote(",\"avro.java.string\":\"String\""), "");
Schema cleanSchema = new Schema.Parser().parse(cleanSchemaJson);

[lukas-krecan]

I have filed an issue to Avro project https://issues.apache.org/jira/browse/AVRO-2838

[peknu]

One way to resolve this is to replace all string types in the avsc file same type that the plugin will generate. For example:
Replace: { "name": "comment", "type": "string" }
With:{ "name": "comment", "type": { "type": "string", "avro.java.string": "String" } }

Keep the avro-maven-plugin config:

<configuration>
    <stringType>String</stringType>
</configuration>

This way, the generated schema inserted into the jar file will be identical with the one used by the plugin to upload and verify schemas. I have only tested that the inserted schema is identical to the one in the avsc file but this should work.

[lukas-krecan]

Yes, but if you work in polyglot environment, it's weird to add avro.java.string to schema

[lukas-krecan]

At the end, we wrapped Jackson Avro serializer and it works like a charm https://github.com/productboardlabs/jackson-kafka-avro-serializer

[rayokota]

This is addressed in 5.5.1 and later by specifying auto.register.schemas=false and use.latest.version=true in the Avro serializer configs.