Error connecting to local Bitnami Docker Kafka from Spring Boot application - docker

Question

Spring Boot (version 2.2) application with Spring Kafka (version 2.4) can't establish a connection with Bitnami Docker Kafka (version 2) executed from the official docker-compose.yml
version: '2'
services:
zookeeper:
image: 'bitnami/zookeeper:3'
ports:
- '2181:2181'
volumes:
- 'zookeeper_data:/bitnami'
environment:
- ALLOW_ANONYMOUS_LOGIN=yes
kafka:
image: 'bitnami/kafka:2'
ports:
- '9092:9092'
volumes:
- 'kafka_data:/bitnami'
environment:
- KAFKA_CFG_ZOOKEEPER_CONNECT=zookeeper:2181
- ALLOW_PLAINTEXT_LISTENER=yes
depends_on:
- zookeeper
volumes:
zookeeper_data:
driver: local
kafka_data:
driver: local
Spring application keeps producing the following warning:
[kafka-admin-client-thread | adminclient-1] WARN o.apache.kafka.clients.NetworkClient.initiateConnect - [AdminClient clientId=adminclient-1] Error connecting to node 2228a9a3b8c5:9092 (id: 1001 rack: null) java.net.UnknownHostException: 2228a9a3b8c5
or
[kafka-admin-client-thread | adminclient-1] WARN o.apache.kafka.clients.NetworkClient.processDisconnection - [AdminClient clientId=adminclient-1] Connection to node -1 (localhost/127.0.0.1:9092) could not be established. Broker may not be available.

Answer 1

To establish connection with Bitnami Docker Kafka running on `localhost, add the following environment variables:
KAFKA_CFG_LISTENERS=PLAINTEXT://:9092
KAFKA_CFG_ADVERTISED_LISTENERS=PLAINTEXT://localhost:9092
docker-compose.yml kafka service:
kafka:
image: 'bitnami/kafka:2'
ports:
- '9092:9092'
volumes:
- 'kafka_data:/bitnami'
environment:
- KAFKA_CFG_ZOOKEEPER_CONNECT=zookeeper:2181
- ALLOW_PLAINTEXT_LISTENER=yes
- KAFKA_CFG_LISTENERS=PLAINTEXT://:9092
- KAFKA_CFG_ADVERTISED_LISTENERS=PLAINTEXT://localhost:9092