Kubernetes compose (Kompose)

kompose is a tool to help users familiar with docker-compose move to Kubernetes. It takes a Docker Compose file and translates it into Kubernetes objects, it can then submit those objects to a Kubernetes endpoint with the kompose up command.

kompose is a convenience tool to go from local Docker development to managing your application with Kubernetes. We don't assume that the transformation from docker compose format to Kubernetes API objects will be perfect, but it helps tremendously to start Kubernetizing your application.

Download

Grab the latest release

Usage

You need a Docker Compose file handy. There is a sample gitlab compose file in the samples/ directory for testing. You will convert the compose file to K8s objects with kompose k8s convert.

$ cd examples/

$ ls
docker-gitlab.yml

$ kompose convert -f docker-gitlab.yml -y

$ ls
docker-gitlab.yml       gitlab-rc.yaml   postgresql-deployment.yaml  postgresql-svc.yaml      redisio-rc.yaml
gitlab-deployment.yaml  gitlab-svc.yaml  postgresql-rc.yaml          redisio-deployment.yaml  redisio-svc.yaml

Next step you will submit these above objects to a kubernetes endpoint that is automatically taken from kubectl.

$ kompose up

Check that the replication controllers and services have been created.

$ kubectl get rc
NAME         DESIRED   CURRENT   AGE
gitlab       1         1         1m
postgresql   1         1         1m
redisio      1         1         1m

$ kubectl get svc
NAME         CLUSTER-IP     EXTERNAL-IP   PORT(S)               AGE
gitlab       10.0.247.129   nodes         10080/TCP,10022/TCP   1m
kubernetes   10.0.0.1       <none>        443/TCP               17h
postgresql   10.0.237.13    <none>        5432/TCP              1m
redisio      10.0.242.93    <none>        6379/TCP              1m

kompose also allows you to list the replication controllers and services with the ps subcommand. You can delete them with the delete subcommand.

$ kompose ps --rc
Name           Containers     Images                        Replicas  Selectors           
redisio        redisio        sameersbn/redis               1         service=redisio
postgresql     postgresql     sameersbn/postgresql:9.4-18   1         service=postgresql
gitlab         gitlab         sameersbn/gitlab:8.6.4        1         service: gitlab

$ kompose ps --svc
Name         Cluster IP          Ports                   Selectors
gitlab       10.0.247.129        TCP(10080),TCP(10022)   service=gitlab
postgresql   10.0.237.13         TCP(5432)               service=postgresql
redisio      10.0.242.93         TCP(6379)               service=redisio


$ kompose delete --rc --name gitlab
$ kompose ps --rc
Name           Containers     Images                        Replicas  Selectors
redisio        redisio        sameersbn/redis               1         service=redisio
postgresql     postgresql     sameersbn/postgresql:9.4-18   1         service=postgresql

And finally you can scale a replication controller with scale.

$ kompose scale --scale 3 --rc redisio
Scaling redisio to: 3
$ kompose ps --rc
Name           Containers     Images                        Replicas  Selectors           
redisio        redisio        sameersbn/redis               3         service=redisio

Note that you can of course manage the services and replication controllers that have been created with kubectl. The command of kompose have been extended to match the docker-compose commands.

Alternate formats

The default kompose transformation will generate replication controllers and services and in format of json. You have alternative option to generate yaml with -y. Also, you can alternatively generate Deployment objects, DeamonSet, ReplicaSet or Helm charts.

$ kompose convert -d -y
$ ls
$ tree
.
├── docker-compose.yml
├── redis-deployment.yaml
├── redis-rc.yaml
├── redis-svc.yaml
├── web-deployment.yaml
└── web-rc.yaml

The *deployment.yaml files contain the Deployments objects

$ kompose convert --ds -y
$ tree .
  .
  ├── redis-daemonset.yaml
  ├── redis-rc.yaml
  ├── redis-svc.yaml
  ├── web-daemonset.yaml
  ├── web-rc.yaml
  └── web-svc.yaml

The *daemonset.yaml files contain the DaemonSet objects

$ kompose convert --rs -y
$ tree .
.
├── redis-rc.yaml
├── redis-replicaset.yaml
├── redis-svc.yaml
├── web-rc.yaml
├── web-replicaset.yaml
└── web-svc.yaml

The *replicaset.yaml files contain the ReplicaSet objects

If you want to generate a Chart to be used with Helm simply do:

$ kompose convert -c -y
$ tree docker-compose/
docker-compose/
├── Chart.yaml
├── README.md
└── templates
    ├── redis-rc.yaml
    ├── redis-svc.yaml
    └── web-rc.yaml

The chart structure is aimed at providing a skeleton for building your Helm charts.

Unsupported docker-compose configuration options

Currently kompose does not support the following Docker Compose options.

"Build", "CapAdd", "CapDrop", "CPUSet", "CPUShares", "ContainerName", "Devices", "DNS", "DNSSearch",
"Dockerfile", "DomainName", "Entrypoint", "EnvFile", "Hostname", "LogDriver", "MemLimit", "MemSwapLimit",
"Net", "Pid", "Uts", "Ipc", "ReadOnly", "StdinOpen", "SecurityOpt", "Tty", "User", "VolumeDriver",
"VolumesFrom", "Expose", "ExternalLinks", "LogOpt", "ExtraHosts",

For example:

$ cat nginx.yml
nginx:
  image: nginx
  dockerfile: foobar
  build: ./foobar
  cap_add:
    - ALL
  container_name: foobar
$ kompose convert -f nginx.yml
WARNING: Unsupported key Build - ignoring
WARNING: Unsupported key CapAdd - ignoring
WARNING: Unsupported key ContainerName - ignoring
WARNING: Unsupported key Dockerfile - ignoring

Bash completion

Running this below command in order to benefit from bash completion

$ PROG=kompose source script/bash_autocomplete

Building

Building with go

• You need go v1.5
• You need to set export GO15VENDOREXPERIMENT=1 environment variable
• If your working copy is not in your GOPATH, you need to set it accordingly.

$ go build -o kompose ./cli/main

Building multi-platform binaries with make

• You need make

$ make binary

Contributing and Issues

kompose is a work in progress, we will see how far it takes us. We welcome any pull request to make it even better. If you find any issues, please file it.

Community, discussion, contribution, and support

Learn how to engage with the Kubernetes community on the community page.

You can reach the maintainers of this project at:

• Slack: #kubernetes-dev
• Mailing List: https://groups.google.com/forum/#!forum/kubernetes-dev

Code of conduct

Participation in the Kubernetes community is governed by the Kubernetes Code of Conduct.