@image_name = "mobylinux/kubernetes"

@versions = {
  kubernetes: "v1.6.1",
  weave: "v1.9.4",
  tini: "v0.14.0",
}

from "gcr.io/google_containers/hyperkube-amd64:#{@versions[:kubernetes]}"

def install_packages pkgs
  cmds = [
    %(apt-get update -q),
    %(apt-get upgrade -qy),
    %(apt-get install -qy #{pkgs}),
  ]

  cmds.each { |cmd| run cmd }
end

def install_dependencies

  prepare = [
    'curl --silent "https://packages.cloud.google.com/apt/doc/apt-key.gpg" | apt-key add -',
    'echo "deb http://apt.kubernetes.io/ kubernetes-xenial main" > /etc/apt/sources.list.d/kubernetes.list',
  ]

  dependencies = %(curl apt-transport-https)

  official_packages = %(kubernetes-cni)

  kube_release_artefacts = "https://dl.k8s.io/#{@versions[:kubernetes]}/bin/linux/amd64"
  weave_launcher = "https://cloud.weave.works/k8s/v1.6/net.yaml?v=#{@versions[:weave]}"

  download_files = [
    "/etc/weave.yaml" => {
      url: weave_launcher,
      mode: '0644',
    },
    "/usr/bin/kubeadm" => {
      url: "#{kube_release_artefacts}/kubeadm",
      mode: '0755',
    },
    "/usr/bin/tini" => {
      url: "https://github.com/krallin/tini/releases/download/#{@versions[:tini]}/tini",
      mode: '0755',
    },
  ]

  install_packages dependencies

  prepare.each { |cmd| run cmd }

  install_packages official_packages

  download_files.each do |file|
    file.each do |dest,info|
      run %(curl --output "#{dest}" --fail --silent --location "#{info[:url]}")
      run %(chmod "#{info[:mode]}" "#{dest}")
    end
  end

end

def kubelet_cmd
  %w(
    /hyperkube kubelet
      --kubeconfig=/var/lib/kubeadm/kubelet.conf --require-kubeconfig=true
      --pod-manifest-path=/var/lib/kubeadm/manifests --allow-privileged=true
      --cluster-dns=10.96.0.10 --cluster-domain=cluster.local
      --cgroups-per-qos=false --enforce-node-allocatable=""
  )
  #--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin
  #--node-ip="192.168.65.2"
end

def create_shell_wrapper script, path
  run "echo \"#!/bin/sh\n#{script}\n\" > #{path} && chmod 0755 #{path}"
end

install_dependencies

# At the moment we trigger `kubeadm init` manually on the master, then start nodes which expect `kubeadm join` args in metadata volume
create_shell_wrapper "until #{kubelet_cmd.join(' ')} ; do [ ! -e /dev/sr0 ] && sleep 1 || (mount -o ro /dev/sr0 /mnt && kubeadm join --skip-preflight-checks \\\$(cat /mnt/config)) ; done", '/usr/bin/kubelet.sh'

create_shell_wrapper "kubeadm init --skip-preflight-checks --kubernetes-version #{@versions[:kubernetes]}", '/usr/bin/kubeadm-init.sh'

flatten

env KUBECONFIG: "/etc/kubernetes/admin.conf"

set_exec entrypoint: %w(tini -s --), cmd: %w(kubelet.sh)

tag "#{@image_name}:latest"