Run Kafka locally (with Docker) and Datadog Agent config to pull metrics from it

docker-compose-ad.yaml

---
version: "3.9"
services:
  zookeeper:
    image: quay.io/debezium/zookeeper:2.3
    ports:
     - 2181:2181
     - 2888:2888
     - 3888:3888
  kafka:
    image: quay.io/debezium/kafka:2.3
    labels:
      com.datadoghq.ad.checks: '{"kafka":{"init_config":{"is_jmx":true},"instances":[{"jmx_url":"service:jmx:rmi://localhost:9999/jndi/rmi://0.0.0.0:9999/jmxrmi","port":9999}]}}'
    ports:
     - 9092:9092
     - 9999:9999
    links:
     - zookeeper
    environment:
     - ZOOKEEPER_CONNECT=zookeeper:2181
     - JMXPORT=9999
     - JMX_PORT=9999
     - JMXHOST=0.0.0.0

docker-compose.yaml

---
version: "3.9"
services:
  zookeeper:
    image: quay.io/debezium/zookeeper:2.3
    ports:
     - 2181:2181
     - 2888:2888
     - 3888:3888
  kafka:
    image: quay.io/debezium/kafka:2.3
    ports:
     - 9092:9092
     - 9999:9999
    links:
     - zookeeper
    environment:
     - ZOOKEEPER_CONNECT=zookeeper:2181
     - JMXPORT=9999
     - JMX_PORT=9999
     - JMXHOST=0.0.0.0

kafka_conf.yaml

---
## All options defined here are available to all instances.
#
init_config:

    ## @param is_jmx - boolean - required
    ## Whether or not this file is a configuration for a JMX integration.
    #
    is_jmx: true

    ## @param collect_default_metrics - boolean - optional - default: false
    ## Whether or not the check should collect all default metrics.
    #
    collect_default_metrics: true

    ## @param new_gc_metrics - boolean - optional - default: false
    ## Set to true to use better metric names for garbage collection metrics.
    ## jvm.gc.cms.count   => jvm.gc.minor_collection_count
    ##                       jvm.gc.major_collection_count
    ## jvm.gc.parnew.time => jvm.gc.minor_collection_time
    ##                       jvm.gc.major_collection_time
    ## The default value is false to ensure backward compatibility.
    #
    new_gc_metrics: true

instances:

    ## @param host - string - required
    ## Kafka host to connect to.
    #
    # - host: 0.0.0.0
    - jmx_url: service:jmx:rmi://localhost:9999/jndi/rmi://0.0.0.0:9999/jmxrmi
      port: 9999

kafka_conf.yaml should be in /etc/datadog-agent/conf.d/kafka.d/conf.yaml