[Question] Example for SASL_PLAINTEXT configuration using official apache/kafka Docker image

[姚泰然]

Hi:

I am looking for a reference or a docker-compose example on how to properly
configure SASL_PLAINTEXT authentication using the official
image(apache/kafka:latest).

I tried the following file, but it is not working:

```yaml
services:
  kafka:
    image: apache/kafka:latest
    container_name: kafka
    hostname: kafka
    restart: always
    extra_hosts:
      - "kafka:127.0.0.1"
    ports:
      - 9092:9092
    environment:
      KAFKA_NODE_ID: 1
      KAFKA_PROCESS_ROLES: broker,controller
      KAFKA_CONTROLLER_QUORUM_VOTERS: 1@kafka:9093
      KAFKA_LOG_RETENTION_HOURS: 72
      KAFKA_NUM_PARTITIONS: 3
      KAFKA_AUTO_CREATE_TOPICS_ENABLE: 'true'
      KAFKA_DEFAULT_REPLICATION_FACTOR: 1
      KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR: 1
      KAFKA_TRANSACTION_STATE_LOG_REPLICATION_FACTOR: 1
      KAFKA_TRANSACTION_STATE_LOG_MIN_ISR: 1

      KAFKA_LISTENERS: CONTROLLER://:9093,BROKER://0.0.0.0:9092
      KAFKA_ADVERTISED_LISTENERS: BROKER://localhost:9092
      KAFKA_LISTENER_SECURITY_PROTOCOL_MAP:
CONTROLLER:PLAINTEXT,BROKER:SASL_PLAINTEXT
      KAFKA_INTER_BROKER_LISTENER_NAME: BROKER
      KAFKA_CONTROLLER_LISTENER_NAMES: CONTROLLER

      KAFKA_SASL_ENABLED_MECHANISMS: PLAIN
      KAFKA_SASL_MECHANISM_INTER_BROKER_PROTOCOL: PLAIN
      KAFKA_LISTENER_NAME_BROKER_SASL_ENABLED_MECHANISMS: PLAIN
      KAFKA_LISTENER_NAME_BROKER_PLAIN_SASL_JAAS_CONFIG:
'org.apache.kafka.common.security.plain.PlainLoginModule required
username="admin" password="123456" user_admin="123456";'

    volumes:
      - kafka_data:/var/lib/kafka/data

volumes:
  kafka_data:
```
`docker logs` output: sasl.jaas.config = null

Thanks for the help.