Wraps commands dependent on STS Tokens through a function using saml2aws, automatically refreshing the session token

s2a_auth.sh

# This function can be added to your bash or zsh rc file - then you setup aliases for
# commonly used tools which rely on AWS session tokens to be refreshed through saml2aws.
s2a_auth() {
  yellow=`tput setaf 3`
  reset=`tput sgr0`

  now_minus_5=$(date -v "-5M" +"%Y-%m-%dT%T%z")
  exp_date=$(awk -F "=" '/x_security_token_expires/ {print $2}' ~/.aws/credentials | tr -d ' ')

  # If a date is not found or there is less than 5 minutes before expiration, re-auth.
  if [ -z "$exp_date" ] || [[ $now_minus_5 > $exp_date ]]; then
    echo -ne "\n${yellow}"
    if [ -z "$exp_date" ]; then
      echo -n "AWS Session Token expiration was not found"
    else
      echo -n "AWS Session Token has expired or is expiring soon"
    fi
    echo "; requesting a new session token...${reset}\n\n"
    saml2aws login --skip-prompt --force
  fi
  
  # Run the command with all arguments
  $@
}

# Example usage
alias aws="s2a_auth aws"
alias terraform="s2a_auth terraform"