Kafka Connect JDBC Sink Connector: Class Loader Not Found - apache-kafka

Question

Using Confluent Docker all in one package with tag 5.4.1; I am struggling to get a jdbc sink connector up and running.
When I launch the following connector:
{
"name": "mySink",
"connector.class": "io.confluent.connect.jdbc.JdbcSinkConnector",
"value.converter": "org.apache.kafka.connect.json.JsonConverter",
"topics": [
"myTopic"
],
"connection.url": "jdbc:sqlserver://sqlserver:1433;databaseName=myDB",
"connection.user": "user",
"connection.password": "**********",
"dialect.name": "SqlServerDatabaseDialect",
"insert.mode": "insert",
"table.name.format": "TableSink",
"pk.mode": "kafka",
"fields.whitelist": [
"offset",
"value"
],
"auto.create": "true"
}
(Some attributes edited)
I get the following exception on from the connect container:
ERROR Plugin class loader for connector: 'io.confluent.connect.jdbc.JdbcSinkConnector' was not found.
I have the following environment variable for connect:
CONNECT_PLUGIN_PATH: "/usr/share/java,/usr/share/confluent-hub-components"
And if I check in the container I have:
/usr/share/java/kafka-connect-jdbc
With the following files:
./jtds-1.3.1.jar
./common-utils-5.4.0.jar
./slf4j-api-1.7.26.jar
./kafka-connect-jdbc-5.4.0.jar
./postgresql-9.4.1212.jar
./sqlite-jdbc-3.25.2.jar
./mssql-jdbc-8.2.0.jre8.jar
./mssql-jdbc-8.2.0.jre13.jar
./mssql-jdbc-8.2.0.jre11.jar
The only changes I have made from the base connect image are the mssql jdbc drivers. These are working fine for a jdbc source connector.
Extra information as requested:
Output from curl -s localhost:8083/connector-plugins|jq '.[].class'
"io.confluent.connect.activemq.ActiveMQSourceConnector"
"io.confluent.connect.elasticsearch.ElasticsearchSinkConnector"
"io.confluent.connect.gcs.GcsSinkConnector"
"io.confluent.connect.ibm.mq.IbmMQSourceConnector"
"io.confluent.connect.jdbc.JdbcSinkConnector"
"io.confluent.connect.jdbc.JdbcSourceConnector"
"io.confluent.connect.jms.JmsSourceConnector"
"io.confluent.connect.s3.S3SinkConnector"
"io.confluent.connect.storage.tools.SchemaSourceConnector"
"io.confluent.kafka.connect.datagen.DatagenConnector"
"org.apache.kafka.connect.file.FileStreamSinkConnector"
"org.apache.kafka.connect.file.FileStreamSourceConnector"
"org.apache.kafka.connect.mirror.MirrorCheckpointConnector"
"org.apache.kafka.connect.mirror.MirrorHeartbeatConnector"
"org.apache.kafka.connect.mirror.MirrorSourceConnector"
docker-compose from:
https://github.com/confluentinc/examples/tree/5.4.1-post/cp-all-in-one
Images:
confluentinc/cp-ksql-cli:5.4.1
confluentinc/cp-enterprise-control-center:5.4.1
confluentinc/cp-ksql-server:5.4.1
cnfldemos/cp-server-connect-datagen:0.2.0-5.4.0
confluentinc/cp-kafka-rest:5.4.1
confluentinc/cp-schema-registry:5.4.1
confluentinc/cp-server:5.4.1
confluentinc/cp-zookeeper:5.4.1