kube-aws

#!/bin/bash

# More safety, by turning some bugs into errors.
set -euCo pipefail
IFS=$'\n\t'

printHelp() {
	echo "<command description>"
	echo "$0 [<optional arguments>] <required arguments>"
	echo ""
	echo "--region file - description"
  echo "--list - list all clusters"
}

# default values
region=""
list="false"
role=""

# arguments parsing
OPTIONS=h:
LONGOPTS=help,list,region:,role:

! PARSED=$(getopt --options=$OPTIONS --longoptions=$LONGOPTS --name "$0" -- "$@")
if [[ ${PIPESTATUS[0]} -ne 0 ]]; then
    exit 2
fi
eval set -- "$PARSED"

while true; do
    case "$1" in
        -h|--help)
			printHelp
			exit 1
            ;;
        --region)
            region="$2"
            shift 2
            ;;
        --role)
            role="$2"
            shift 2
            ;;
        --list)
            list="true"
            shift
            ;;
        --)
            shift
            break
            ;;
        *)
            echo "Programming error"
            exit 3
            ;;
    esac
done

function cleanup() {
	rm "$configFile" > /dev/null 2>&1 || true
	rmdir "$tempDirectory" > /dev/null 2>&1 || true
}

trap "cleanup" EXIT

tempDirectory="$(mktemp -d)"
configFile="$tempDirectory/config"

printAllEksClusters() {
  allRegions="$(aws ec2 describe-regions --query 'Regions[].RegionName' | jq -r .[])"

  for region in $allRegions; do
    clusters="$(aws eks list-clusters --region "$region" --output json | jq -r '.clusters[]')"
    if [ -n "$clusters" ]; then
      echo "Region $region has clusters: $clusters"
    fi
  done
  exit 1
}

if [[ "$list" == "true" ]]; then
  printAllEksClusters
  exit 0
fi

if [[ -z "$region" ]]; then
  region="$(aws configure get region)"
fi

if [[ -z "${1-}" ]]; then
  clusters="$(aws eks list-clusters --region "$region" --output json | jq -r '.clusters[]')"

  if [[ -z "$clusters" ]]; then
    echo >&2 "No EKS clusters found"
    exit 1
  fi

  clusterCount="$(echo "$clusters" | wc -l)"

  if [[ "$clusterCount" == 1 ]]; then
    cluster="$(echo "$clusters" | head -n 1)"
  else
    echo >&2 "Please select cluster. Multiple EKS clusters available: $(echo "$clusters" | tr ' ' ',')."
    echo >&2 "Usage: $0 [<cluster>]"
    exit 1
  fi
else
  cluster="$1"
  shift
fi

function getRole() {
  local clusterRoleName="AWS_EKS_ROLE_${cluster^^}"

  if [[ -n "$role" ]]; then
    echo "$role"
  elif [[ -n "${!clusterRoleName:-}" ]]; then
    echo "${!clusterRoleName}"
  elif [[ -n "${AWS_EKS_ROLE-}" ]]; then
    echo "$AWS_EKS_ROLE"
  fi
}

role="$(getRole)"

aws eks update-kubeconfig --name "$cluster" --region "$region" --kubeconfig "$configFile" ${role:+--role-arn} ${role:+$role}

export KUBECONFIG="$configFile"
export DOCKER_MACHINE_NAME="k8s:$cluster"

if [[ -z "${1-}" ]]; then
	fish
else
	"$@"
fi