How to use VS code java debugger and Kafka Connect inside of Docker Compose

You need to bind *:5005 and KAFKA_DEBUG=y won't do this. I found out the hard way and found this https://www.mrjamiebowman.com/software-development/kafka/debugging-kafka-connect-connectors-smts-in-java/ to help me.

  connect:
    image: quay.io/debezium/connect:2.6
    ports:
      - 8083:8083
      - 5005:5005
    environment:
      - BOOTSTRAP_SERVERS=kafka:9092
      - GROUP_ID=1
      - CONFIG_STORAGE_TOPIC=my_connect_configs
      - OFFSET_STORAGE_TOPIC=my_connect_offsets
      - STATUS_STORAGE_TOPIC=my_source_connect_statuses
      - CONNECT_PLUGIN_PATH=/kafka/connect,/opt/connectors
      - JAVA_TOOL_OPTIONS="-agentlib:jdwp=transport=dt_socket,address=*:5005,server=y,suspend=n"
#      - KAFKA_DEBUG=y
#      - DEBUG_SUSPEND_FLAG=y
    depends_on:
      kafka:
        condition: service_healthy
    volumes:
      - ./kafka-connect-connectors-jar:/opt/connectors

Kafka Connect in debug mode

The error you get if you don’t bind correctly (just :5005)

atwong@Albert-CelerData ~ % jdb -attach 5005
java.net.SocketException: Connection reset
 at java.base/java.net.SocketInputStream.read(SocketInputStream.java:186)
 at java.base/java.net.SocketInputStream.read(SocketInputStream.java:140)
 at jdk.jdi/com.sun.tools.jdi.SocketTransportService.handshake(SocketTransportService.java:136)
 at jdk.jdi/com.sun.tools.jdi.SocketTransportService.attach(SocketTransportService.java:255)
 at jdk.jdi/com.sun.tools.jdi.GenericAttachingConnector.attach(GenericAttachingConnector.java:119)
 at jdk.jdi/com.sun.tools.jdi.SocketAttachingConnector.attach(SocketAttachingConnector.java:83)
 at jdk.jdi/com.sun.tools.example.debug.tty.VMConnection.attachTarget(VMConnection.java:546)
 at jdk.jdi/com.sun.tools.example.debug.tty.VMConnection.open(VMConnection.java:356)
 at jdk.jdi/com.sun.tools.example.debug.tty.Env.init(Env.java:63)
 at jdk.jdi/com.sun.tools.example.debug.tty.TTY.main(TTY.java:1091)

Fatal error:
Unable to attach to target VM.

My launch.json

{
    "configurations": [
    {
        "type": "java",
        "name": "Attach to Remote Program",
        "request": "attach",
        "hostName": "localhost",
        "port": "5005"
    }
    ]
}