Translate a Docker Compose File to Kubernetes Resources
What's Kompose? It's a conversion tool for all things compose (namely Docker Compose) to container orchestrators (Kubernetes or OpenShift).
More information can be found on the Kompose website at
You need to have a Kubernetes cluster, and the kubectl command-line tool must
be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a
cluster, you can create one by using
minikube
or you can use one of these Kubernetes playgrounds:Before you begin
kubectl version
.
Install Kompose
We have multiple ways to install Kompose. Our preferred method is downloading the binary from the latest GitHub release.
Kompose is released via GitHub on a three-week cycle, you can see all current releases on the .
# Linux
curl -L https://github.com/kubernetes/kompose/releases/download/v1.26.0/kompose-linux-amd64 -o kompose
# macOS
curl -L https://github.com/kubernetes/kompose/releases/download/v1.26.0/kompose-darwin-amd64 -o kompose
# Windows
curl -L https://github.com/kubernetes/kompose/releases/download/v1.26.0/kompose-windows-amd64.exe -o kompose.exe
chmod +x kompose
sudo mv ./kompose /usr/local/bin/kompose
Installing using go get
pulls from the master branch with the latest development changes.
go get -u github.com/kubernetes/kompose
If you have
sudo yum -y install kompose
Kompose is in Fedora 24, 25 and 26 repositories. You can install it like any other package.
sudo dnf -y install kompose
On macOS you can install latest release via
brew install kompose
Use Kompose
In a few steps, we'll take you from Docker Compose to Kubernetes. All
you need is an existing docker-compose.yml
file.
-
Go to the directory containing your
docker-compose.yml
file. If you don't have one, test using this one.version: "2" services: redis-master: image: k8s.gcr.io/redis:e2e ports: - "6379" redis-slave: image: gcr.io/google_samples/gb-redisslave:v3 ports: - "6379" environment: - GET_HOSTS_FROM=dns frontend: image: gcr.io/google-samples/gb-frontend:v4 ports: - "80:80" environment: - GET_HOSTS_FROM=dns labels: kompose.service.type: LoadBalancer
-
To convert the
docker-compose.yml
file to files that you can use withkubectl
, runkompose convert
and thenkubectl apply -f <output file>
.kompose convert
The output is similar to:
INFO Kubernetes file "frontend-service.yaml" created INFO Kubernetes file "frontend-service.yaml" created INFO Kubernetes file "frontend-service.yaml" created INFO Kubernetes file "redis-master-service.yaml" created INFO Kubernetes file "redis-master-service.yaml" created INFO Kubernetes file "redis-master-service.yaml" created INFO Kubernetes file "redis-slave-service.yaml" created INFO Kubernetes file "redis-slave-service.yaml" created INFO Kubernetes file "redis-slave-service.yaml" created INFO Kubernetes file "frontend-deployment.yaml" created INFO Kubernetes file "frontend-deployment.yaml" created INFO Kubernetes file "frontend-deployment.yaml" created INFO Kubernetes file "redis-master-deployment.yaml" created INFO Kubernetes file "redis-master-deployment.yaml" created INFO Kubernetes file "redis-master-deployment.yaml" created INFO Kubernetes file "redis-slave-deployment.yaml" created INFO Kubernetes file "redis-slave-deployment.yaml" created INFO Kubernetes file "redis-slave-deployment.yaml" created
kubectl apply -f frontend-service.yaml,redis-master-service.yaml,redis-slave-service.yaml,frontend-deployment.yaml,redis-master-deployment.yaml,redis-slave-deployment.yaml
The output is similar to:
service/frontend created service/redis-master created service/redis-slave created deployment.apps/frontend created deployment.apps/redis-master created deployment.apps/redis-slave created
Your deployments are running in Kubernetes.
-
Access your application.
If you're already using
minikube
for your development process:minikube service frontend
Otherwise, let's look up what IP your service is using!
kubectl describe svc frontend
Name: frontend Namespace: default Labels: service=frontend Selector: service=frontend Type: LoadBalancer IP: 10.0.0.183 LoadBalancer Ingress: 192.0.2.89 Port: 80 80/TCP NodePort: 80 31144/TCP Endpoints: 172.17.0.4:80 Session Affinity: None No events.
If you're using a cloud provider, your IP will be listed next to
LoadBalancer Ingress
.curl http://192.0.2.89
User Guide
- CLI
- Documentation
Kompose has support for two providers: OpenShift and Kubernetes.
You can choose a targeted provider using global option --provider
. If no provider is specified, Kubernetes is set by default.
kompose convert
Kompose supports conversion of V1, V2, and V3 Docker Compose files into Kubernetes and OpenShift objects.
Kubernetes kompose convert
example
kompose --file docker-voting.yml convert
WARN Unsupported key networks - ignoring
WARN Unsupported key build - ignoring
INFO Kubernetes file "worker-svc.yaml" created
INFO Kubernetes file "db-svc.yaml" created
INFO Kubernetes file "redis-svc.yaml" created
INFO Kubernetes file "result-svc.yaml" created
INFO Kubernetes file "vote-svc.yaml" created
INFO Kubernetes file "redis-deployment.yaml" created
INFO Kubernetes file "result-deployment.yaml" created
INFO Kubernetes file "vote-deployment.yaml" created
INFO Kubernetes file "worker-deployment.yaml" created
INFO Kubernetes file "db-deployment.yaml" created
ls
db-deployment.yaml docker-compose.yml docker-gitlab.yml redis-deployment.yaml result-deployment.yaml vote-deployment.yaml worker-deployment.yaml
db-svc.yaml docker-voting.yml redis-svc.yaml result-svc.yaml vote-svc.yaml worker-svc.yaml
You can also provide multiple docker-compose files at the same time:
kompose -f docker-compose.yml -f docker-guestbook.yml convert
INFO Kubernetes file "frontend-service.yaml" created
INFO Kubernetes file "mlbparks-service.yaml" created
INFO Kubernetes file "mongodb-service.yaml" created
INFO Kubernetes file "redis-master-service.yaml" created
INFO Kubernetes file "redis-slave-service.yaml" created
INFO Kubernetes file "frontend-deployment.yaml" created
INFO Kubernetes file "mlbparks-deployment.yaml" created
INFO Kubernetes file "mongodb-deployment.yaml" created
INFO Kubernetes file "mongodb-claim0-persistentvolumeclaim.yaml" created
INFO Kubernetes file "redis-master-deployment.yaml" created
INFO Kubernetes file "redis-slave-deployment.yaml" created
ls
mlbparks-deployment.yaml mongodb-service.yaml redis-slave-service.jsonmlbparks-service.yaml
frontend-deployment.yaml mongodb-claim0-persistentvolumeclaim.yaml redis-master-service.yaml
frontend-service.yaml mongodb-deployment.yaml redis-slave-deployment.yaml
redis-master-deployment.yaml
When multiple docker-compose files are provided the configuration is merged. Any configuration that is common will be over ridden by subsequent file.
OpenShift kompose convert
example
kompose --provider openshift --file docker-voting.yml convert
WARN [worker] Service cannot be created because of missing port.
INFO OpenShift file "vote-service.yaml" created
INFO OpenShift file "db-service.yaml" created
INFO OpenShift file "redis-service.yaml" created
INFO OpenShift file "result-service.yaml" created
INFO OpenShift file "vote-deploymentconfig.yaml" created
INFO OpenShift file "vote-imagestream.yaml" created
INFO OpenShift file "worker-deploymentconfig.yaml" created
INFO OpenShift file "worker-imagestream.yaml" created
INFO OpenShift file "db-deploymentconfig.yaml" created
INFO OpenShift file "db-imagestream.yaml" created
INFO OpenShift file "redis-deploymentconfig.yaml" created
INFO OpenShift file "redis-imagestream.yaml" created
INFO OpenShift file "result-deploymentconfig.yaml" created
INFO OpenShift file "result-imagestream.yaml" created
It also supports creating buildconfig for build directive in a service. By default, it uses the remote repo for the current git branch as the source repo, and the current branch as the source branch for the build. You can specify a different source repo and branch using --build-repo
and --build-branch
options respectively.
kompose --provider openshift --file buildconfig/docker-compose.yml convert
WARN [foo] Service cannot be created because of missing port.
INFO OpenShift Buildconfig using git@github.com:rtnpro/kompose.git::master as source.
INFO OpenShift file "foo-deploymentconfig.yaml" created
INFO OpenShift file "foo-imagestream.yaml" created
INFO OpenShift file "foo-buildconfig.yaml" created
oc create -f
, you need to ensure that you push the imagestream artifact before the buildconfig artifact, to workaround this OpenShift issue:
Alternative Conversions
The default The The The kompose
transformation will generate Kubernetes Deployments and Services, in yaml format. You have alternative option to generate json with -j
. Also, you can alternatively generate Replication Controllers objects, Daemon Sets, or
kompose convert -j
INFO Kubernetes file "redis-svc.json" created
INFO Kubernetes file "web-svc.json" created
INFO Kubernetes file "redis-deployment.json" created
INFO Kubernetes file "web-deployment.json" created
*-deployment.json
files contain the Deployment objects.kompose convert --replication-controller
INFO Kubernetes file "redis-svc.yaml" created
INFO Kubernetes file "web-svc.yaml" created
INFO Kubernetes file "redis-replicationcontroller.yaml" created
INFO Kubernetes file "web-replicationcontroller.yaml" created
*-replicationcontroller.yaml
files contain the Replication Controller objects. If you want to specify replicas (default is 1), use --replicas
flag: kompose convert --replication-controller --replicas 3
kompose convert --daemon-set
INFO Kubernetes file "redis-svc.yaml" created
INFO Kubernetes file "web-svc.yaml" created
INFO Kubernetes file "redis-daemonset.yaml" created
INFO Kubernetes file "web-daemonset.yaml" created
*-daemonset.yaml
files contain the DaemonSet objects
Key | Value |
---|---|
kompose.service.type | nodeport / clusterip / loadbalancer |
kompose.service.expose | true / hostname |
kompose.service.type
label should be defined with ports
only, otherwise kompose
will fail.
Restart
If you want to create normal pods without controllers you can use restart
construct of docker-compose to define that. Follow table below to see what happens on the restart
value.
docker-compose restart |
object created | Pod restartPolicy |
---|---|---|
"" |
controller object | Always |
always |
controller object | Always |
on-failure |
Pod | OnFailure |
no |
Pod | Never |
deployment
or replicationcontroller
.
For example, the pival
service will become pod down here. This container calculated value of pi
.
version: '2'
services:
pival:
image: perl
command: ["perl", "-Mbignum=bpi", "-wle", "print bpi(2000)"]
restart: "on-failure"
Warning about Deployment Configurations
If the Docker Compose file has a volume specified for a service, the Deployment (Kubernetes) or DeploymentConfig (OpenShift) strategy is changed to "Recreate" instead of "RollingUpdate" (default). This is done to avoid multiple instances of a service from accessing a volume at the same time.
If the Docker Compose file has service name with _
in it (eg.web_service
), then it will be replaced by -
and the service name will be renamed accordingly (eg.web-service
). Kompose does this because "Kubernetes" doesn't allow _
in object name.
Please note that changing service name might break some docker-compose
files.
Docker Compose Versions
Kompose supports Docker Compose versions: 1, 2 and 3. We have limited support on versions 2.1 and 3.2 due to their experimental nature.
A full list on compatibility between all three versions is listed in our