Demo - From Kafka Streams To Kafka Connectors

This Repository is created to help those who wants to set up Confluent Kafka Cluster, MySql in Docker Desktop. Then produce the messages using Kafka Producer Template, then these messages will be processed using Kafka Streams Processor and then posted to MySql using Kafka Connect API (with JDBC Connector)

I have used below tech stack

• Spring Boot

• Spring Integration

• Spring Kafka

• Kafka streams

• Confluent Kafka [Connect - JDBC Connector, Schema Registry, Avros]

• Kotlin

REST Ops

# Available Connectors
http://localhost:8083/connectors

#Installed Plugins
http://localhost:8083/connector-plugins

#Install a JDBC Connector Plugin
curl -X POST \
  -H "Content-Type: application/json" \
  --data '{ "name" : "mysql-sink-connector", "config" : { "connection.url" : "jdbc:mysql://mysql:3306/deals_db", "connection.user" : "<replace_username>", "connection.password" : "<replace_password>", "connection.attempts" : "3", "connection.backoff.ms" : "5000", "table.whitelist" : "deals_db.ALERTSUBSCRIPTION", "table.name.format" : "deals_db.ALERTSUBSCRIPTION", "db.timezone" : "UTC", "connector.class" : "io.confluent.connect.jdbc.JdbcSinkConnector", "dialect.name" : "MySqlDatabaseDialect", "auto.create" : "true", "auto.evolve" : "true", "tasks.max" : "1", "batch.size" : "10", "topics" : "deals_topic_processed", "value.converter.schema.enable":"true", "key.converter.schemas.enable": "false", "key.converter" :"org.apache.kafka.connect.storage.StringConverter", "value.converter" : "io.confluent.connect.avro.AvroConverter", "value.converter.schema.registry.url" : "http://schema-registry:8081", "insert.mode" : "INSERT", "pk.mode" : "none" }}' \
  http://localhost:8083/connectors

#Get Installed Plugin Status
http://localhost:8083/connectors/mysql-sink-connector/status

Maven Commands

• Setup the Environment i.e. Kafka & MySQL with below command

    $> docker compose up -d

• Start Kafka Producer with below command

    $> cd kafka-producer
    $> mvn spring-boot:run -Dspring.profiles.active=avro

• If you just want to consume above messages start consumer app

    $> cd kafka-consumer
    $> mvn spring-boot:run -Dspring.profiles.active=avro

• To post to messages to Database using JDBC Connector, start the processor app with below command

    $> cd stream-processor
    $> mvn spring-boot:run -Dspring.profiles.active=avro

Open Database Explorer of your own choice (I am using IntelliJ - Database Tool)

Query the Table that you have provided in schema

You should see data flowing to Mysql

Helpful References

Kafka Connector Ref- MySQL

Database Identifiers, Case Sensitivity Guidelines

Troubleshooting JDBC Connectors

Kafka Connect Official Github Repo

Confluent Cluster Docker YML Reference

Confluent Kafka Examples - Demo Scene

~ Happy Learning!

Questions with setup? Find me in LinkedIn