我需要創建一個已創建主題的 kafka 圖像

Question

我有一個要求，我需要使用容器中已有的主題在本地設置 kafka。我正在使用ladoop/fast-data-dev來執行此操作

我是如何手動操作的-

docker run -d --name landoopkafka -p 2181:2181 -p 3030:3030 -p 8081:8081 -p 8082:8082 -p 8083:8083 -p 9092:9092 -e ADV_HOST=localhost landoop/fast-data-dev

運行此命令后，我的容器已啟動並正在運行。

現在我在這個容器內的 go 到 bash 就像 docker -exec -it landopkafka ZD576914BB40C9998CCE691

並使用此命令創建主題

kafka-topics --zookeeper localhost:2181 --create --topic hello_topic --partitions 1 --replication-factor 1

我的主題已創建。

但我的要求是我需要一個 docker 文件，該文件將創建主題，我只需要運行它。

或者

我需要運行的 docker 撰寫文件

伙計們，我需要幫助，因為我對 docker 和 kafka 完全陌生

Answer 1

我也必須這樣做！ 如果我不想使用wurstmeister圖像怎么辦？ 我決定制作一個自定義腳本來完成這項工作，並在一個單獨的容器中運行這個腳本。

存儲庫

https://github.com/yan-khonski-it/kafka-compose

請注意，它適用於使用zookeeper的 kafka 版本。 Zookeeper 是 Kafka 的必備工具嗎？

使用所有主題和 zookeeper 啟動 kafka - docker-compose up -d 。

---

實施細節。

docker-compose.yml

# These services are kafka related. This docker-compose allows to start kafka locally quickly.

version: '2.1'

networks:
  demo-network:
    name: demo-network
    driver: bridge

services:
  zookeeper:
    image: "confluentinc/cp-zookeeper:${CONFLUENT_PLATFORM_VERSION}"
    container_name: zookeeper
    environment:
      ZOOKEEPER_CLIENT_PORT: 32181
      ZOOKEEPER_TICK_TIME: 2000
    ports:
      - 32181:32181
    hostname: zookeeper
    networks:
      - demo-network

  kafka:
    image: "confluentinc/cp-kafka:${CONFLUENT_PLATFORM_VERSION}"
    container_name: kafka
    hostname: kafka
    ports:
      - 9092:9092
      - 29092:29092

    environment:
      KAFKA_ZOOKEEPER_CONNECT: zookeeper:32181
      KAFKA_BROKER_ID: 1
      KAFKA_LISTENER_SECURITY_PROTOCOL_MAP: PLAINTEXT:PLAINTEXT,PLAINTEXT_HOST:PLAINTEXT
      KAFKA_ADVERTISED_LISTENERS: PLAINTEXT://localhost:9092,PLAINTEXT_HOST://kafka:29092
      LISTENERS: PLAINTEXT://0.0.0.0:9092
      KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR: 1

    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
    depends_on:
      - "zookeeper"
    networks:
      - demo-network

  # Automatically creates required kafka topics if they were not created.
  kafka-topics-creator:
    build:
      context: kafka-topic-creator
      dockerfile: Dockerfile
    container_name: kafka-topics-creator
    depends_on:
      - zookeeper
      - kafka
    environment:
      ZOOKEEPER_HOSTS: "zookeeper:32181"
      KAFKA_TOPICS: "topic_v1 topic_v2"
    networks:
      - demo-network

然后我有一個目錄kafka-topics-creator 。 在這里，我有三個文件create-kafka-topics.sh ， Dockerfile ， README.md 。

Dockerfile

# It is recommened to use same version as kafka broker is used.
# So no additional images are pulled.
FROM confluentinc/cp-kafka:4.1.2

WORKDIR usr/bin

# Once it is executed, this container is not needed.
COPY create-kafka-topics.sh create-kafka-topics.sh
ENTRYPOINT ["./create-kafka-topics.sh"]

創建-kafka-topics.sh

#!/bin/bash

# Simply wait until original kafka container and zookeeper are started.
sleep 15.0s

# Parse string of kafka topics into an array
# https://stackoverflow.com/a/10586169/4587961
kafkatopicsArrayString="$KAFKA_TOPICS"
IFS=' ' read -r -a kafkaTopicsArray <<< "$kafkatopicsArrayString"

# A separate variable for zookeeper hosts.
zookeeperHostsValue=$ZOOKEEPER_HOSTS

# Create kafka topic for each topic item from split array of topics.
for newTopic in "${kafkaTopicsArray[@]}"; do
  # https://kafka.apache.org/quickstart
  kafka-topics --create --topic "$newTopic" --partitions 1 --replication-factor 1 --if-not-exists --zookeeper "$zookeeperHostsValue"
done

README.md - 所以其他人知道如何使用它。總是記錄你的東西 - 好建議。

# Creates kafka topics automatically.

## Parameters
`ZOOKEEPER_HOSTS` - zookeeper hosts,  I used value `"zookeeper:32181"` to run it locally.

`KAFKA_TOPICS` - space separated list of kafka topics. Example, `topic_1, topic_2, topic_3`.

Note, this container should run only **after** your original kafka broker and zookeeper are running.
After this container creates topics, it is not needed anymore.

如何檢查主題是否已創建。

一種解決方案是檢查kafka-topics-creator容器的日志。

docker logs kafka-topics-creator應該打印

$ docker logs kafka-topics-creator
WARNING: Due to limitations in metric names, topics with a period ('.') or underscore ('_') could collide. To avoid issues it is best to use either, but not both.
Created topic "topic_v1".
WARNING: Due to limitations in metric names, topics with a period ('.') or underscore ('_') could collide. To avoid issues it is best to use either, but not both.
Created topic "topic_v2".

Answer 2

您應該嘗試使用支持環境變量的 wurstmeister/kafka 映像在容器啟動期間創建主題。

當然，Landoop 容器還有很多其他有用的東西，但聽起來你只想要 Kafka 而不想搞亂編輯任何 Dockerfile

另一種解決方案是在運行創建腳本的Kafka 之后啟動第二個容器，然后自行停止

Answer 3

您可以像這樣創建 docker-compose 文件...

version: '2'

services:
  zookeeper:
      image: wurstmeister/zookeeper:latest
      ports:
        - "2181:2181"

  kafka:
      image: wurstmeister/kafka:0.10.2.1
      ports:
        - "9092:9092"
      environment:
        KAFKA_ADVERTISED_HOST_NAME: 127.0.0.1
        KAFKA_CREATE_TOPICS: "MY_TOPIC_ONE:1:1,/
                              MY_TOPIC_TWO:1:1"
        KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
      volumes:
        - /var/run/docker.sock:/var/run/docker.sock

將您的主題放在那里並運行docker-compose up