How to set up Kafka-connector to use custom transform in Debezium?

Question

I'm new to Kafka and I can't figure out how to use "transforms.router.type" to make it work with my Debezium setup. So I made special event transformation java class and prepeared configuration for it to deploy to container which looks like this:

curl -X POST -H "Accept:application/json" -H "Content-Type:application/json" localhost:8083/connectors/ -d

{
  "name": "task-connector",
  "config": {
    "connector.class": "io.debezium.connector.postgresql.PostgresConnector",
    "tasks.max": "1",
    "slot.name" : "task_engine_saga",
    "database.hostname": "postgres",
    "database.port": "5432",
    "database.user": "postgres",
    "database.password": "postgres",
    "database.dbname" : "tasks",
    "schema.whitelist": "public",
    "table.whitelist" : "public.task",
    "tombstones.on.delete" : "false",
    "transforms" : "router",
    "transforms.router.type" : "com.task.connect.TaskEventRouter"
  }
}

And the response says that this config can't be found.

CREATE kafka connector task-connector....
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  1091  100   516  100   575   8322   9274 --:--:-- --:--:-- --:--:-- 17596{"error_code":400,"message":"Connector configuration is invalid and contains the following 3 error(s):\nInvalid value com.task.connect.TaskEventRouter for configuration transforms.router.type: Class com.task.connect.TaskEventRouter could not be found.\nInvalid value null for configuration transforms.router.type: Not a Transformation\nA value is required\nYou can also find the above list of errors at the endpoint `/connector-plugins/{connectorType}/config/validate`"}

Then I copied to container /connect directory my host folder with jar file in which I have my java class with event transformation logic, but it didn't help too. Could someone please help me and tell what should I do to make this custom transforms.router.type work with my Debezium set up?

My containers docker-compose set up:

version: '3'
services:
    pgadmin:
        container_name: pgadmin_container
        image: dpage/pgadmin4
        environment:
            PGADMIN_DEFAULT_EMAIL: ${PGADMIN_DEFAULT_EMAIL:-pgadmin4@pgadmin.org}
            PGADMIN_DEFAULT_PASSWORD: ${PGADMIN_DEFAULT_PASSWORD:-admin}
        volumes:
            - pgadmin:/root/.pgadmin
        ports:
            - "${PGADMIN_PORT:-5050}:80"
        restart: unless-stopped

    zookeeper:
        image: debezium/zookeeper:1.3
        ports:
            - 2181:2181
            - 2888:2888
            - 3888:3888
    kafka:
        image: debezium/kafka:1.3
        ports:
            - 9092:9092
        links:
            - zookeeper
        environment:
            - ZOOKEEPER_CONNECT=zookeeper:2181
    postgres:
        image: debezium/example-postgres:1.3
        ports:
            - 5432:5432
        environment:
            - POSTGRES_USER=postgres
            - POSTGRES_PASSWORD=postgres
            - PGDATA=/data/postgres
            - POSTGRES_DB=${POSTGRES_DB:-task_engine}
    connect:
        image: debezium/connect:1.3
        ports:
            - 8083:8083
        links:
            - kafka
            - postgres
        environment:
            - BOOTSTRAP_SERVERS=kafka:9092
            - GROUP_ID=1
            - CONFIG_STORAGE_TOPIC=my_connect_configs
            - OFFSET_STORAGE_TOPIC=my_connect_offsets
            - STATUS_STORAGE_TOPIC=my_connect_statuses

volumes:
    postgres:
    pgadmin:

Answer 1

I made special event transformation java class

From what I can tell, you have not mounted this compiled class into your debezium image or edited the plugin.path file to include that JAR

If you have created your own Docker image with that data, then you should change image: debezium/connect:1.3

This would explain why the transform is not available