update_es_data.sh

#!/bin/sh

CDIR=$(cd `dirname "$0"` && pwd)
cd "$CDIR"

print_red() {
  printf '%b' "\033[91m$1\033[0m\n"
}

print_green() {
  printf '%b' "\033[92m$1\033[0m\n"
}

render_template() {
  eval "echo \"$(cat "$1")\""
}

#KUBECTL_PARAMS="--context=foo"
NAMESPACE=${NAMESPACE:-monitoring}
KUBECTL="kubectl ${KUBECTL_PARAMS} --namespace=\"${NAMESPACE}\""

NODES=$(eval "${KUBECTL} get nodes -o go-template=\"{{range .items}}{{\\\$name := .metadata.name}}{{\\\$unschedulable := .spec.unschedulable}}{{range .status.conditions}}{{if eq .reason \\\"KubeletReady\\\"}}{{if eq .status \\\"True\\\"}}{{if not \\\$unschedulable}}{{\\\$name}}{{\\\"\\\\n\\\"}}{{end}}{{end}}{{end}}{{end}}{{end}}\"")
ES_DATA_REPLICAS=$(echo "$NODES" | wc -l)

if [ "$ES_DATA_REPLICAS" -lt 3 ]; then
  print_red "Minimum amount of Elasticsearch data nodes is 3 (in case when you have 1 replica shard), you have ${ES_DATA_REPLICAS} worker nodes"
  print_red "Won't deploy more than one Elasticsearch data pod per node exiting..."
  exit 1
fi

render_template es-data.yaml.tmpl | eval "${KUBECTL} replace -f -"

eval "${KUBECTL} get pods $@"