plugin-drone-helm/DOCS.md

### Simple Usage

For example, this configuration will deploy my-app using a chart located in the repo called `my-chart`

```YAML
pipeline:
  helm_deploy:
    image: quay.io/ipedrazas/drone-helm
    skip_tls_verify: true
    chart: ./charts/my-chart
    release: ${DRONE_BRANCH}
    values: secret.password=${SECRET_PASSWORD},image.tag=${DRONE_BRANCH}-${DRONE_COMMIT_SHA:0:7}
    prefix: STAGING
    debug: true
    wait: true
    when:
      branch: [master]
```

Last update of Drone expect you to declare the secrets you want to use:

```YAML
pipeline:
  helm_deploy:
    image: quay.io/ipedrazas/drone-helm
    chart: ./chart/blog
    release: ${DRONE_BRANCH}-blog
    values: image.tag=${DRONE_BRANCH}-${DRONE_COMMIT_SHA:0:7}
    prefix: PROD
    secrets: [ prod_api_server, prod_kubernetes_token ]
    when:
      branch: [master]
```

Use Kubernetes Certificate Authority Data. Just add the `<prefix>_kubernetes_certificate` secret

```diff
  helm_deploy:
    image: quay.io/ipedrazas/drone-helm
    chart: ./chart/blog
    release: ${DRONE_BRANCH}-blog
    values: image.tag=${DRONE_BRANCH}-${DRONE_COMMIT_SHA:0:7}
    prefix: PROD
    - secrets: [ prod_api_server, prod_kubernetes_token ]
    + secrets: [ prod_api_server, prod_kubernetes_token, prod_kubernetes_certificate ]
    when:
      branch: [master]
```

### Using Values and Value files

Values can be passed using the `values_files` key. Use this option to define your values in a set of files
and pass them to `helm`. This option trigger the `-f` or ``--values`` flag in `helm`:

```plain
--values valueFiles   specify values in a YAML file (can specify multiple) (default [])
```

For example:

```YAML
pipeline:
  helm_deploy:
    image: quay.io/ipedrazas/drone-helm
    skip_tls_verify: true
    chart: ./charts/my-chart
    release: ${DRONE_BRANCH}
    values_files: ["global-values.yaml", "myenv-values.yaml"]
    when:
      branch: [master]
```

### Using private Repositories

Charts can also be fetched from your own private Chart Repository. `helm_repos` accepts a comma separated list of key value pairs where the key is the repository name and the value is the repository url.

For Example:

```YAML
pipeline:
  helm_deploy_staging:
    image: quay.io/ipedrazas/drone-helm
    skip_tls_verify: true
    helm_repos: hb-charts=http://helm-charts.honestbee.com
    chart: hb-charts/hello-world
    values: image.repository=quay.io/honestbee/hello-drone-helm,image.tag=${DRONE_BRANCH}-${DRONE_COMMIT_SHA:0:7}
    release: ${DRONE_REPO_NAME}-${DRONE_BRANCH}
    prefix: STAGING
    when:
      branch:
        exclude: [ master ]
```

## Updating Chart dependencies

In some cases, the local Chart might contain external dependencies defined in `./charts/my-chart/requirements.yaml`, e.g.:

```YAML
dependencies:
  - name: redis
    version: 3.3.6
    repository: '@stable'
```

To restore these dependecies before the deployment `update_dependencies` parameter should be used, e.g.:

```YAML
pipeline:
  helm_deploy:
    image: quay.io/ipedrazas/drone-helm
    skip_tls_verify: true
    chart: ./charts/my-chart
    update_dependencies: true
    release: ${DRONE_BRANCH}
    values_files: ["global-values.yaml", "myenv-values.yaml"]
    when:
      branch: [master]
```

## Drone Secrets

There are two secrets you have to create (Note that if you specify the prefix, your secrets have to be created using that prefix):

```bash
drone secret add --image=quay.io/ipedrazas/drone-helm \
  your-user/your-repo STAGING_API_SERVER https://mykubernetesapiserver

drone secret add --image=quay.io/ipedrazas/drone-helm \
  your-user/your-repo STAGING_KUBERNETES_TOKEN eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJrdWJ...

drone secret add --image=quay.io/ipedrazas/drone-helm \
  your-user/your-repo STAGING_SECRET_PASSWORD Sup3rS3cr3t
```

`Prefix` helps you to use the same block in different environments:

```YAML
pipeline:
  helm_deploy_staging:
    image: quay.io/ipedrazas/drone-helm
    skip_tls_verify: true
    chart: ./charts/my-chart
    release: ${DRONE_BRANCH}
    values: secret.password=${SECRET_PASSWORD},image.tag=${DRONE_BRANCH}-${DRONE_COMMIT_SHA:0:7}
    prefix: STAGING
    debug: true
    wait: true
    when:
      branch:
        exclude: [ master ]

pipeline_production:
  helm_deploy:
    image: quay.io/ipedrazas/drone-helm
    skip_tls_verify: true
    chart: ./charts/my-chart
    release: ${DRONE_BRANCH}
    values: secret.password=${SECRET_PASSWORD},image.tag=${DRONE_BRANCH}-${DRONE_COMMIT_SHA:0:7}
    prefix: PROD
    debug: true
    wait: true
    when:
      branch: [master]
```

This last block defines how the plugin will deploy

## Testing with Minikube

To test the plugin, you can run `minikube` and just run the docker image as follows:

By using the docker daemon of minikube we can test local builds without having to push to a registry:

```bash
eval $(minikube docker-env)
```

Build the image locally

```bash
./build.sh
```

Get the token for the default service account in the default namespace:

```bash
KUBERNETES_TOKEN=$(kubectl get secret $(kubectl get sa default -o jsonpath='{.secrets[].name}{"\n"}') -o jsonpath="{.data.token}" | base64 -D)
```

## Advanced customisations and debugging

This plugin installs [Tiller](https://github.com/kubernetes/helm/blob/master/docs/architecture.md) in the cluster, if you want to specify the namespace where `tiller` ins installed, use the `tiller_ns` attribute.

The following example will install `tiller` in the `operations` namespace:

```YAML
pipeline_production:
  helm_deploy:
    image: quay.io/ipedrazas/drone-helm
    skip_tls_verify: true
    chart: ./charts/my-chart
    release: ${DRONE_BRANCH}
    values: image.tag=${DRONE_BRANCH}-${DRONE_COMMIT_SHA:0:7}
    prefix: PROD
    tiller_ns: operations
    when:
      branch: [master]
```

There's an option to do a `dry-run` in case you want to verify that the secrets and envvars are replaced correctly. Just add the attribute `dry-run` to true:

```YAML
pipeline_production:
  helm_deploy:
    image: quay.io/ipedrazas/drone-helm
    skip_tls_verify: true
    chart: ./charts/my-chart
    release: ${DRONE_BRANCH}
    values: image.tag=${DRONE_BRANCH}-${DRONE_COMMIT_SHA:0:7}
    prefix: STAGING
    dry-run:true
    when:
      branch: [master]
```

Happy Helming!

## Known issues

* Drone secrets that are part of `values` can be leaked in debug mode and in case of error as the whole helm command will be printed in the logs. See #52