Unable to run a JDBC Source connector with Confluent REST API

Question

I want to run a JDBC source connector using Kafka Connect REST API. Although stand-alone mode works perfect using the following properties file:

name=source-mysql-test
connector.class=io.confluent.connect.jdbc.JdbcSourceConnector
tasks.max=1

connection.url=jdbc:mysql://localhost:3306/kafka
connection.user=myuser
connection.password=mypass


table.whitelist=MY_TABLE

# Pull all rows based on timestamp
mode=timestamp
timestamp.column.name=ROWVERSION
validate.non.null=false

# The Kafka topic will be made up of this prefix, plus the table name.
topic.prefix=MYSQL-

table.types=TABLE,VIEW
poll.interval.ms=1000

I am not able to run the connector using the REST API. Here's the call:

curl -X POST -H "Content-Type: application/json" --data '{"name": "source-mysql-test", "config": {"connector.class":"io.confluent.connect.jdbc.JdbcSourceConnector", "tasks.max":"1", "connection.url":"jdbc:mysql://localhost:3306/kafka","connection.user":"myuser","connection.password":"mypass", "table.whitelist":"MY_TABLE", "mode":"timestamp", "timestamp.column.name":"ROWVERSION", "validate.non.null":"false", "topic.prefix":"MYSQL-", "table.types":"TABLE,VIEW", "poll.interval.ms":"1000" }}' http://localhost:8083/connectors

And here's the response:

{
  "error_code": 400,
  "message": "Connector configuration is invalid and contains the following 2 error(s):\nInvalid value com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. for configuration Couldn't open connection to jdbc:mysql://localhost:3306/kafka\nInvalid value com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. for configuration Couldn't open connection to jdbc:mysql://localhost:3306/kafka\nYou can also find the above list of errors at the endpoint `/{connectorType}/config/validate`"
}

In the past I have used the REST API in order to run JDBC sink connectors without any problems!

Here are the available connector plugins:

> ls /usr/share/java/kafka-connect-jdbc/
common-utils-4.1.0.jar        mysql-connector-java-5.1.46.jar  uber-restavro-1.0-SNAPSHOT.jar
jline-0.9.94.jar              netty-3.10.5.Final.jar          
kafka-connect-jdbc-4.1.0.jar  postgresql-9.4-1206-jdbc41.jar   zkclient-0.10.jar
log4j-1.2.17.jar              slf4j-api-1.7.25.jar             zookeeper-3.4.10.jar
mssql-jdbc-6.2.2.jre8.jar     sqlite-jdbc-3.8.11.2.jar

Answer 1

The problem seems to be the compatibility of the JDBC Connector with MySQL 8. I've upgraded MySQL Connector/J from 5.1.46 to 8.0.11 and the issue has been fixed.