--- assignees: - cdrage title: Translating a Docker Compose File to Kubernetes Resources redirect_from: - "/docs/tools/kompose/" - "/docs/tools/kompose/index.html" --- * TOC {:toc} `kompose` is a tool to help users who are familiar with `docker-compose` move to **Kubernetes**. `kompose` takes a Docker Compose file and translates it into Kubernetes resources. More information about Kompose can be found on the official [http://kompose.io](http://kompose.io/) site. `kompose` is a convenience tool to go from local Docker development to managing your application with Kubernetes. Transformation of the Docker Compose format to Kubernetes resources manifest may not be exact, but it helps tremendously when first deploying an application on Kubernetes. ## Use Case If you have a Docker Compose `docker-compose.yml` or a Docker Distributed Application Bundle `docker-compose-bundle.dab` file, you can convert it into Kubernetes deployments and services like this: ```console $ kompose -f docker-compose.yml convert WARN: Unsupported key networks - ignoring file "redis-svc.yaml" created file "web-svc.yaml" created file "web-deployment.yaml" created file "redis-deployment.yaml" created ``` ## Installation We have multiple ways to install Kompose. Our prefered method is downloading the binary from the latest GitHub release. ### GitHub release Kompose is released via GitHub on a three-week cycle, you can see all current releases on the [GitHub release page](https://github.com/kubernetes-incubator/kompose/releases). The current release we use is `0.5.0`. ```sh # Linux curl -L https://github.com/kubernetes-incubator/kompose/releases/download/v0.5.0/kompose-linux-amd64 -o kompose # macOS curl -L https://github.com/kubernetes-incubator/kompose/releases/download/v0.5.0/kompose-darwin-amd64 -o kompose # Windows curl -L https://github.com/kubernetes-incubator/kompose/releases/download/v0.5.0/kompose-windows-amd64.exe -o kompose.exe ``` Make the binary executable and move it to your PATH (e.g. `/usr/local/bin`) ```sh chmod +x kompose sudo mv ./kompose /usr/local/bin/kompose ``` ## Kompose convert Currently Kompose supports to transform either Docker Compose file (both of v1 and v2) and [experimental Distributed Application Bundles](https://blog.docker.com/2016/06/docker-app-bundle/) into Kubernetes and OpenShift objects. There is a couple of sample files in the `examples/` directory for testing. You will convert the compose or dab file to Kubernetes or OpenShift objects with `kompose convert`. ### Kubernetes ```console $ cd examples/ $ ls docker-compose.yml docker-compose-bundle.dab docker-gitlab.yml docker-voting.yml $ kompose -f docker-gitlab.yml convert file "redisio-svc.yaml" created file "gitlab-svc.yaml" created file "postgresql-svc.yaml" created file "gitlab-deployment.yaml" created file "postgresql-deployment.yaml" created file "redisio-deployment.yaml" created $ ls *.yaml gitlab-deployment.yaml postgresql-deployment.yaml redis-deployment.yaml redisio-svc.yaml web-deployment.yaml gitlab-svc.yaml postgresql-svc.yaml redisio-deployment.yaml redis-svc.yaml web-svc.yaml ``` You can try with a Docker Compose version 2 like this: ```console $ kompose --file docker-voting.yml convert WARN Unsupported key networks - ignoring WARN Unsupported key build - ignoring file "worker-svc.yaml" created file "db-svc.yaml" created file "redis-svc.yaml" created file "result-svc.yaml" created file "vote-svc.yaml" created file "redis-deployment.yaml" created file "result-deployment.yaml" created file "vote-deployment.yaml" created file "worker-deployment.yaml" created 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-compose-bundle.dab 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: ```console $ kompose -f docker-compose.yml -f docker-guestbook.yml convert file "frontend-service.yaml" created file "mlbparks-service.yaml" created file "mongodb-service.yaml" created file "redis-master-service.yaml" created file "redis-slave-service.yaml" created file "frontend-deployment.yaml" created file "mlbparks-deployment.yaml" created file "mongodb-deployment.yaml" created file "mongodb-claim0-persistentvolumeclaim.yaml" created file "redis-master-deployment.yaml" created 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. Using `--bundle, --dab` to specify a DAB file as below: ```console $ kompose --bundle docker-compose-bundle.dab convert WARN: Unsupported key networks - ignoring file "redis-svc.yaml" created file "web-svc.yaml" created file "web-deployment.yaml" created file "redis-deployment.yaml" created ``` ### OpenShift ```console $ kompose --provider openshift --file docker-voting.yml convert WARN [worker] Service cannot be created because of missing port. INFO file "vote-service.yaml" created INFO file "db-service.yaml" created INFO file "redis-service.yaml" created INFO file "result-service.yaml" created INFO file "vote-deploymentconfig.yaml" created INFO file "vote-imagestream.yaml" created INFO file "worker-deploymentconfig.yaml" created INFO file "worker-imagestream.yaml" created INFO file "db-deploymentconfig.yaml" created INFO file "db-imagestream.yaml" created INFO file "redis-deploymentconfig.yaml" created INFO file "redis-imagestream.yaml" created INFO file "result-deploymentconfig.yaml" created INFO file "result-imagestream.yaml" created ``` In similar way you can convert DAB files to OpenShift. ```console $ kompose --bundle docker-compose-bundle.dab --provider openshift convert WARN: Unsupported key networks - ignoring INFO file "redis-svc.yaml" created INFO file "web-svc.yaml" created INFO file "web-deploymentconfig.yaml" created INFO file "web-imagestream.yaml" created INFO file "redis-deploymentconfig.yaml" created INFO file "redis-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. ```console $ kompose --provider openshift --file buildconfig/docker-compose.yml convert WARN [foo] Service cannot be created because of missing port. INFO Buildconfig using git@github.com:rtnpro/kompose.git::master as source. INFO file "foo-deploymentconfig.yaml" created INFO file "foo-imagestream.yaml" created INFO file "foo-buildconfig.yaml" created ``` **Note**: If you are manually pushing the Openshift artifacts using ``oc create -f``, you need to ensure that you push the imagestream artifact before the buildconfig artifact, to workaround this Openshift issue: https://github.com/openshift/origin/issues/4518 . ## Kompose up Kompose supports a straightforward way to deploy your "composed" application to Kubernetes or OpenShift via `kompose up`. ### Kubernetes ```console $ kompose --file ./examples/docker-guestbook.yml up We are going to create Kubernetes deployments and services for your Dockerized application. If you need different kind of resources, use the 'kompose convert' and 'kubectl create -f' commands instead. INFO Successfully created service: redis-master INFO Successfully created service: redis-slave INFO Successfully created service: frontend INFO Successfully created deployment: redis-master INFO Successfully created deployment: redis-slave INFO Successfully created deployment: frontend Your application has been deployed to Kubernetes. You can run 'kubectl get deployment,svc,pods' for details. $ kubectl get deployment,svc,pods NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE deploy/frontend 1 1 1 1 4m deploy/redis-master 1 1 1 1 4m deploy/redis-slave 1 1 1 1 4m NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE svc/frontend 10.0.174.12 80/TCP 4m svc/kubernetes 10.0.0.1 443/TCP 13d svc/redis-master 10.0.202.43 6379/TCP 4m svc/redis-slave 10.0.1.85 6379/TCP 4m NAME READY STATUS RESTARTS AGE po/frontend-2768218532-cs5t5 1/1 Running 0 4m po/redis-master-1432129712-63jn8 1/1 Running 0 4m po/redis-slave-2504961300-nve7b 1/1 Running 0 4m ``` Note: - You must have a running Kubernetes cluster with a pre-configured kubectl context. - Only deployments and services are generated and deployed to Kubernetes. If you need different kind of resources, use the 'kompose convert' and 'kubectl create -f' commands instead. ### OpenShift ```console $kompose --file ./examples/docker-guestbook.yml --provider openshift up We are going to create OpenShift DeploymentConfigs and Services for your Dockerized application. If you need different kind of resources, use the 'kompose convert' and 'oc create -f' commands instead. INFO Successfully created service: redis-slave INFO Successfully created service: frontend INFO Successfully created service: redis-master INFO Successfully created deployment: redis-slave INFO Successfully created ImageStream: redis-slave INFO Successfully created deployment: frontend INFO Successfully created ImageStream: frontend INFO Successfully created deployment: redis-master INFO Successfully created ImageStream: redis-master Your application has been deployed to OpenShift. You can run 'oc get dc,svc,is' for details. $ oc get dc,svc,is NAME REVISION DESIRED CURRENT TRIGGERED BY dc/frontend 0 1 0 config,image(frontend:v4) dc/redis-master 0 1 0 config,image(redis-master:e2e) dc/redis-slave 0 1 0 config,image(redis-slave:v1) NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE svc/frontend 172.30.46.64 80/TCP 8s svc/redis-master 172.30.144.56 6379/TCP 8s svc/redis-slave 172.30.75.245 6379/TCP 8s NAME DOCKER REPO TAGS UPDATED is/frontend 172.30.12.200:5000/fff/frontend is/redis-master 172.30.12.200:5000/fff/redis-master is/redis-slave 172.30.12.200:5000/fff/redis-slave v1 ``` Note: - You must have a running OpenShift cluster with a pre-configured `oc` context (`oc login`) ## Kompose down Once you have deployed "composed" application to Kubernetes, `kompose down` will help you to take the application out by deleting its deployments and services. If you need to remove other resources, use the 'kubectl' command. ```console $ kompose --file docker-guestbook.yml down INFO Successfully deleted service: redis-master INFO Successfully deleted deployment: redis-master INFO Successfully deleted service: redis-slave INFO Successfully deleted deployment: redis-slave INFO Successfully deleted service: frontend INFO Successfully deleted deployment: frontend ``` Note: - You must have a running Kubernetes cluster with a pre-configured kubectl context. ## Alternate formats The default `kompose` transformation will generate Kubernetes [Deployments](http://kubernetes.io/docs/user-guide/deployments/) and [Services](http://kubernetes.io/docs/user-guide/services/), in yaml format. You have alternative option to generate json with `-j`. Also, you can alternatively generate [Replication Controllers](http://kubernetes.io/docs/user-guide/replication-controller/) objects, [Deamon Sets](http://kubernetes.io/docs/admin/daemons/), or [Helm](https://github.com/helm/helm) charts. ```console $ kompose convert -j file "redis-svc.json" created file "web-svc.json" created file "redis-deployment.json" created file "web-deployment.json" created ``` The `*-deployment.json` files contain the Deployment objects. ```console $ kompose convert --rc file "redis-svc.yaml" created file "web-svc.yaml" created file "redis-rc.yaml" created file "web-rc.yaml" created ``` The `*-rc.yaml` files contain the Replication Controller objects. If you want to specify replicas (default is 1), use `--replicas` flag: `$ kompose convert --rc --replicas 3` ```console $ kompose convert --ds file "redis-svc.yaml" created file "web-svc.yaml" created file "redis-daemonset.yaml" created file "web-daemonset.yaml" created ``` The `*-daemonset.yaml` files contain the Daemon Set objects If you want to generate a Chart to be used with [Helm](https://github.com/kubernetes/helm) simply do: ```console $ kompose convert -c file "web-svc.yaml" created file "redis-svc.yaml" created file "web-deployment.yaml" created file "redis-deployment.yaml" created chart created in "./docker-compose/" $ tree docker-compose/ docker-compose ├── Chart.yaml ├── README.md └── templates ├── redis-deployment.yaml ├── redis-svc.yaml ├── web-deployment.yaml └── web-svc.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 some Docker Compose options, which are listed on the [conversion](http://kompose.io/conversion/) document. For example: ```console $ cat nginx.yml nginx: image: nginx dockerfile: foobar build: ./foobar cap_add: - ALL container_name: foobar $ kompose -f nginx.yml convert WARN Unsupported key build - ignoring WARN Unsupported key cap_add - ignoring WARN Unsupported key dockerfile - ignoring ``` ## Labels `kompose` supports Kompose-specific labels within the `docker-compose.yml` file in order to explicitly define a service's behavior upon conversion. - kompose.service.type defines the type of service to be created. For example: ```yaml version: "2" services: nginx: image: nginx dockerfile: foobar build: ./foobar cap_add: - ALL container_name: foobar labels: kompose.service.type: nodeport ``` - kompose.service.expose defines if the service needs to be made accessible from outside the cluster or not. If the value is set to "true", the provider sets the endpoint automatically, and for any other value, the value is set as the hostname. If multiple ports are defined in a service, the first one is chosen to be the exposed. - For the Kubernetes provider, an ingress resource is created and it is assumed that an ingress controller has already been configured. - For the OpenShift provider, a route is created. For example: ```yaml version: "2" services: web: image: tuna/docker-counter23 ports: - "5000:5000" links: - redis labels: kompose.service.expose: "counter.example.com" redis: image: redis:3.0 ports: - "6379" ``` The currently supported options are: | Key | Value | |----------------------|-------------------------------------| | kompose.service.type | nodeport / clusterip / loadbalancer | | kompose.service.expose| true / hostname | ## 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 heppens 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` | **Note**: controller object could be `deployment` or `replicationcontroller`, etc. ```yaml version: '2' services: pival: image: perl command: ["perl", "-Mbignum=bpi", "-wle", "print bpi(2000)"] restart: "on-failure" ``` #### Warning about DeploymentConfig 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.