Cache EKS tokens for kubectl

cache-eks-token.sh

#!/bin/bash

# usage mimics aws execution to replace just the command, not args
function usage() {
  echo "Usage: $0 --region eu-west-2 eks get-token --cluster-name prod"
}

if [ -z "$1" ]; then
  usage
  exit 1
fi
REGION=$2
CLUSTER_NAME=$6

NOW=$(date +%s)
TOKEN_FILE="$HOME/.kube/.${REGION}-${CLUSTER_NAME}.eks-token"

if [ -f "${TOKEN_FILE}" ]; then
  ACCESS_TIME=$(date -r "${TOKEN_FILE}" +%s)
  if [[ $((NOW-800)) -gt ${ACCESS_TIME} ]]; then
    GENERATE_NEW_TOKEN="true"
  fi
  # In case the credential file exists but is messed up, we'll generate a new one
  if [[ $(grep -q 'ExecCredential' "${TOKEN_FILE}"; echo $?) -gt 0 ]]; then
    GENERATE_NEW_TOKEN="true"
  fi
else
  GENERATE_NEW_TOKEN="true"
fi

if [[ ${GENERATE_NEW_TOKEN} == "true" ]]; then
    aws eks get-token \
      --region "${REGION}" \
      --cluster-name "${CLUSTER_NAME}" > "${TOKEN_FILE}"
fi
cat "${TOKEN_FILE}"

Save this script to ~/bin/ directory and replace command: aws with command: ../bin/cache-eks-token.sh inside your $KUBECONFIG or ${HOME}/.kube/config etc, f.e.

sed -i "" 's#command: aws#command: ../bin/cache-eks-token.sh#' ${KUBECONFIG}