Flink in Docker

This is a Docker image appropriate for running Flink in Kuberenetes. You can also run it locally with docker-compose in which case you get two containers by default:

• flink-jobmanager - runs a Flink Job Manager in cluster mode and exposes a port for Flink and a port for the WebUI.
• flink-taskmanager - runs a Flink Task Manager and connects to the Flink Job Manager via static DNS name flink-jobmanager.

The Docker setup is heavily influenced by docker-flink

Usage

Build

You only need to build the Docker image if you have changed Dockerfile or the startup shell script, otherwise skip to the next step and start using directly.

To build, get the code from Github, change as desired and build an image by running make

Run locally

Get the docker-compose.yml from Github and then use the following snippets

Start JobManager and TaskManager

docker-compose up -d will start a Job Manager with a single Task Manager in background.

Scale TaskManagers

docker-compose scale flink-taskmanager=5 will scale to 5 Task Managers.

Deploy and Run a Job

1. Copy the Flink job JAR to the Job Manager

docker cp /path/to/job.jar $(docker ps --filter name=flink-jobmanager --format={{.ID}}):/job.jar to

2. Copy the data to each Flink node if necessary

for i in $(docker ps --filter name=flink --format={{.ID}}); do
  docker cp /path/to/data.csv $i:/data.csv
done

3. Run the job

docker exec -it $(docker ps --filter name=flink-jobmanager --format={{.ID}}) flink run -c <your_job_class> /job.jar [optional params]

where optional params could for example point to the dataset copied at the previous step.

Accessing Flink Web Dashboard

Navigate to http://localhost:8081

Stop Flink Cluster

docker-compose down shuts down the cluster.

Contribution

You are very welcome to open an issue or a PR on Github.