[Bug]: Solace Connect plugin crashes in Strimzi

[kbreit-insight]

Bug Description

Note: I am starting this with Strimzi but the issue may need to exist in Kafka Connect or Solace instead.

I am trying to deploy the Solace Kafka source connector (https://github.com/SolaceProducts/pubsubplus-connector-kafka-source) to Strimzi/Kafka. However, it crashes and provides a Java traceback. Also, someone submitted an issue in 2022 to the Solace connector (SolaceProducts/pubsubplus-connector-kafka-source#41) that came up with Confluent, but seems to be a similar problem.

Steps to reproduce

1. Deploy Strimzi.
2. Create a KafkaConnect resource.
3. Create a KafkaConnector custom resource.
4. Wait for pods to come up and watch the logs of the connect pod.
5. Here are the logs.

Expected behavior

It shouldn't crash.

Strimzi version

0.43.0

Kubernetes version

1.29.8

Installation method

Helm chart

Infrastructure

AKS

Configuration files and logs

apiVersion: kafka.strimzi.io/v1beta2
kind: KafkaConnect
metadata:
  name: solace
  namespace: kafka
  annotations:
    strimzi.io/use-connector-resources: "true"
spec:
  bootstrapServers: 10.100.12.5:31030
  build:
    plugins:
      - name: solace
        artifacts:
          - type: zip
            url: https://solaceproducts.github.io/pubsubplus-connector-kafka-source/downloads/pubsubplus-connector-kafka-source-3.1.0.zip
    output:
      type: docker
      image: your_registry.azurecr.io/your_repo/kafka-connect-solace:0.0.2
      pushSecret: acr-creds
  template:
    pod:
      imagePullSecrets:
        - name: acr-creds

apiVersion: kafka.strimzi.io/v1beta2
kind: KafkaConnector
metadata:
  name: solace-source-connector
  namespace: kafka
  labels:
    strimzi.io/cluster: solace
spec:
  class: com.solace.connector.kafka.connect.source.SolaceSourceConnector
  tasksMax: 1
  config:
    value.converter: org.apache.kafka.connect.converters.ByteArrayConverter
    key.converter: org.apache.kafka.connect.storage.StringConverter
    kafka.topic: swim
    sol.host: tcps://your_host.example.com
    sol.username: your_user
    sol.password: p@ssword
    sol.vpn_name: vpn_name
    sol.topics: some_topic

2024-10-10 13:28:49,532 INFO [solace-source-connector|task-0] ==================Initialize Connector properties (com.solace.connector.kafka.connect.source.SolaceSourceConnectorConfig) [task-thread-solace-source-connector-0]
2024-10-10 13:28:49,533 ERROR [solace-source-connector|task-0] WorkerSourceTask{id=solace-source-connector-0} Task threw an uncaught and unrecoverable exception. Task is being killed and will not recover until manually restarted (org.apache.kafka.connect.runtime.WorkerTask) [task-thread-solace-source-connector-0]
org.apache.kafka.connect.errors.ConnectException: Encountered exception in creating the message processor.
	at com.solace.connector.kafka.connect.source.SolaceSourceTask.start(SolaceSourceTask.java:74)
	at org.apache.kafka.connect.runtime.AbstractWorkerSourceTask.initializeAndStart(AbstractWorkerSourceTask.java:278)
	at org.apache.kafka.connect.runtime.WorkerTask.doStart(WorkerTask.java:175)
	at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:224)
	at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:280)
	at org.apache.kafka.connect.runtime.AbstractWorkerSourceTask.run(AbstractWorkerSourceTask.java:78)
	at org.apache.kafka.connect.runtime.isolation.Plugins.lambda$withClassLoader$1(Plugins.java:237)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:840)
Caused by: org.apache.kafka.common.KafkaException: Could not find a public no-argument constructor for com.solace.connector.kafka.connect.source.SolMessageProcessorIF
	at org.apache.kafka.common.utils.Utils.newInstance(Utils.java:401)
	at org.apache.kafka.common.config.AbstractConfig.getConfiguredInstance(AbstractConfig.java:397)
	at org.apache.kafka.common.config.AbstractConfig.getConfiguredInstance(AbstractConfig.java:436)
	at org.apache.kafka.common.config.AbstractConfig.getConfiguredInstance(AbstractConfig.java:421)
	at com.solace.connector.kafka.connect.source.SolaceSourceTask.start(SolaceSourceTask.java:71)
	... 11 more
Caused by: java.lang.NoSuchMethodException: com.solace.connector.kafka.connect.source.SolMessageProcessorIF.<init>()
	at java.base/java.lang.Class.getConstructor0(Class.java:3585)
	at java.base/java.lang.Class.getDeclaredConstructor(Class.java:2754)
	at org.apache.kafka.common.utils.Utils.newInstance(Utils.java:399)
	... 15 more

Additional context

No response

[scholzj]

As I explained on Slack ... this has nothing to do with Strimzi. It is an error from a connector you get when running it in Kafka Connect. Strimzi code has nothing to do with this. This should be closed.

[kbreit-insight]

I was able to resolve this problem. Instead of using SolaceSourceConnector I moved to ``SolaceSampleSourceConnector` and it resolved the problem. I'm thinking the former needs to be extended into custom connectors, which is why it didn't work.