kompose/docs/user-guide.md

144 lines
5.0 KiB
Markdown

# User Guide
## Usage
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 objects. There is a couple of sample files in the `examples/` directory for testing. You will convert the compose or dab file to K8s objects with `kompose convert`.
```console
$ cd examples/
$ ls
docker-compose.yml docker-compose-bundle.dsb docker-gitlab.yml docker-voting.yml
$ kompose convert -f docker-gitlab.yml -y
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 convert --file docker-voting.yml
WARN[0000]: Unsupported key networks - ignoring
WARN[0000]: Unsupported key build - ignoring
file "worker-svc.json" created
file "db-svc.json" created
file "redis-svc.json" created
file "result-svc.json" created
file "vote-svc.json" created
file "redis-deployment.json" created
file "result-deployment.json" created
file "vote-deployment.json" created
file "worker-deployment.json" created
file "db-deployment.json" created
$ ls
db-deployment.json docker-compose.yml docker-gitlab.yml redis-deployment.json result-deployment.json vote-deployment.json worker-deployment.json
db-svc.json docker-compose-bundle.dsb docker-voting.yml redis-svc.json result-svc.json vote-svc.json worker-svc.json
```
Using `--bundle, --dab` to specify a DAB file as below:
```console
$ kompose convert --bundle docker-compose-bundle.dsb
WARN[0000]: Unsupported key networks - ignoring
file "redis-svc.json" created
file "web-svc.json" created
file "web-deployment.json" created
file "redis-deployment.json" created
```
## 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 json format. You have alternative option to generate yaml with `-y`. 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
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 -y
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 -y`
```console
$ kompose convert --ds -y
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 -y
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 the following Docker Compose options.
```
"build", "cap_add", "cap_drop", "cpuset", "cpu_shares", "cpu_quota", "cgroup_parent", "devices", "depends_on", "dns",
"dns_search", "domainname", "entrypoint", "env_file", "expose", "extends", "external_links", "extra_hosts", "hostname", "ipc",
"logging", "mac_address", "mem_limit", "memswap_limit", "network_mode", "networks", "pid", "security_opt", "shm_size",
"stop_signal", "volume_driver", "volumes_from", "uts", "read_only", "stdin_open", "tty", "user", "ulimits", "dockerfile",
"net", "args"
```
For example:
```console
$ cat nginx.yml
nginx:
image: nginx
dockerfile: foobar
build: ./foobar
cap_add:
- ALL
container_name: foobar
$ kompose convert -f nginx.yml
WARN[0000] Unsupported key build - ignoring
WARN[0000] Unsupported key cap_add - ignoring
WARN[0000] Unsupported key dockerfile - ignoring
```