Alpine image to control Kubernetes on Azure using Helm and Draft

Dockerfile-k8s-admin

#
# Custom Dockerfile
# - based on Alpine linux
# - install AzureCLI v2.0
# - install Helm [Kubernetes (more than) package manager]
# - install kubectl
# Usage:
# Build it and push it to the private registry.
# Gitlab will use it to interact with Azure Kubernetes and Registry [AKS, ACR]
#

FROM alpine
ENV HELM_LATEST_VERSION="v2.7.2"
# --- > TODO
#ENV AZURE_CLI_LATEST_VERSION=""

##### Notice: Install AzureCLI 2.0 #####
RUN apk update && \
  apk add --no-cache git && \
  apk add bash curl make py-pip && \
  apk add --virtual=build gcc libffi-dev musl-dev openssl-dev python2-dev && \
  pip install azure-cli && \
  apk del --purge build

##### Notice: Install Helm #####
RUN apk add --update ca-certificates \
 && apk add --update -t deps wget \
 && wget http://storage.googleapis.com/kubernetes-helm/helm-${HELM_LATEST_VERSION}-linux-amd64.tar.gz \
 && tar -xvf helm-${HELM_LATEST_VERSION}-linux-amd64.tar.gz \
 && mv linux-amd64/helm /usr/local/bin \
 && apk del --purge deps \
 && rm /var/cache/apk/* \
 && rm -f /helm-${HELM_LATEST_VERSION}-linux-amd64.tar.gz

##### Notice: Install kubectl #####
# Note: Latest version may be found on:
# https://aur.archlinux.org/packages/kubectl-bin/
ADD https://storage.googleapis.com/kubernetes-release/release/v1.6.4/bin/linux/amd64/kubectl /usr/local/bin/kubectl
ENV HOME=/config
RUN set -x && \
    apk add --no-cache curl ca-certificates && \
    chmod +x /usr/local/bin/kubectl && \
    \
    # Create non-root user (with a randomly chosen UID/GUI).
    adduser kubectl -Du 2342 -h /config && \
    \
    # Basic check it works.
    kubectl version --client

###### Notice: Install envsubst #####
## check here: https://github.com/cirocosta/alpine-envsubst/blob/master/Dockerfile
## here: https://serverfault.com/questions/791715/using-environment-variables-in-kubernetes-deployment-spec
#RUN set -x && \
#    apk add --update libintl && \
#    apk add --virtual build_deps gettext &&  \
#    cp /usr/bin/envsubst /usr/local/bin/envsubst && \
#    apk del build_deps

####### Notice: Install Draft #####
### check here: https://github.com/Azure/draft/blob/master/docs/install.md
###
#RUN curl https://azuredraft.blob.core.windows.net/draft/draft-canary-linux-amd64.tar.gz | tar xvz && \
#    cp linux-amd64/draft /usr/bin && \
#    rm -rf linux-amd64

CMD ["sh"]