Kafka is a distributed streaming platform that lets you publish and subscribe to streams of records in fault-tolerant way and lets you process streams of records as they occur.
NOTE: This image is no longer maintained. See confluentinc/cp-kafka for Kafka images.
Kafka is a distributed system that uses Zookeeper to coordinate Kafka brokers and keep track of Kafka topics and partitions. Before starting Kafka, you need a Zookeeper service that it can connect to. The official zookeeper image can be used to create and start a Zookeeper container.
docker run --name zookeeper -d zookeeper
Next, create and start a Kafka container, with a link to the Zookeeper container. This Kafka image is pre-configured to connect to Zookeeper using the service name zookeeper on port 2181, the default Zookeeper client port.
docker run --name kakfa --link zookeeper:zookeeper -d ucalgary/kafka
Docker Compose files can be used to define and run multi-container systems. Since Kafka requires Zookeeper to run, a Compose file is a great way to define the two services and deploy them together.
Here is a simple Compose file that defines services for Zookeeper and Kafka.
version: '3'
services:
zookeeper:
image: zookeeper
kafka:
image: ucalgary/kafka
depends_on:
- zookeeper
Both services will be connected to a default network for this stack when it is brought up using Docker Compose or deployed as a stack in swarm mode. Containers for the kafka service can automatically connect to zookeeper containers via the service name.
The depends_on parameter expresses a dependency from the kafka service to the zookeeper service. If you specifically tell Docker Compose to start the kafka service, Docker Compose will also start the zookeeper service because of the declared dependency.
Note: depends_on does not apply for Docker stack deployments.