doc(README): description, drone example

README.md

@@ -1,3 +1,64 @@
 # helm-docker
 
-Hello
+[![Build Status](https://drone.cryptic.systems/api/badges/volker.raschek/helm-docker/status.svg)](https://drone.cryptic.systems/volker.raschek/helm-docker)
+[![Docker Pulls](https://img.shields.io/docker/pulls/volkerraschek/helm)](https://hub.docker.com/r/volkerraschek/helm)
+
+This project contains all sources to build the container image
+`docker.io/volkerraschek/helm`. The primary goal of this project is to package
+the binary `helm` as container image to provide the functionally for CI/CD
+workflows. The source code of the binary can be found in the upstream project of
+[helm](github.com/helm/helm).
+
+## drone
+
+Here is an example to lint, package and deploy a chart to chartmuseum via
+`docker.io/volkerraschek/helm`.
+
+```yaml
+kind: pipeline
+type: kubernetes
+name: linter
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+- name: helm lint
+  commands:
+  - helm lint
+  image: docker.io/volkerraschek/helm:latest
+  resources:
+    limits:
+      cpu: 50
+      memory: 50M
+
+---
+kind: pipeline
+type: kubernetes
+name: release
+
+platform:
+  os: linux
+
+steps:
+- name: release-helm-chart
+  commands:
+  - helm plugin install https://github.com/chartmuseum/helm-push.git
+  - helm repo add myrepo https://charts.example.com/myrepo
+  - helm package --version ${DRONE_TAG} .
+  - helm cm-push ${DRONE_REPO_NAME}-${DRONE_TAG}.tgz myrepo
+  environment:
+    HELM_REPO_PASSWORD:
+      from_secret: helm_repo_password
+    HELM_REPO_USERNAME:
+      from_secret: helm_repo_username
+  image: docker.io/volkerraschek/helm:latest
+  resources:
+    limits:
+      cpu: 50
+      memory: 50M
+trigger:
+  event:
+  - tag
+```