TKI function for Bash prompt

tki-bash.sh

# If AWS credentials have been updated in the last 12 hours, TKI is probably ok.
CHECK_TKI=false # Change to 'true' to enable the check.
function warn_tki {
    if [[ -e "$HOME/.aws/credentials" && $CHECK_TKI == 'true' ]]; then
        date_format="%Y%m%d%H%M%S" # Reduces time to a comparable number, not epoch dependant.
        mod_time=$(date --reference="$HOME/.aws/credentials") # Time AWS creds were modified.
        expire_time=$(date --date="$mod_time + 43200 seconds" +"$date_format") # Add 12 hours.

        if [[ "$expire_time" -ge "$(date +$date_format)" ]]; then
            echo -e '\033[0;32mTKI:✓ ' # Green
        else
            echo -e '\033[0;31mTKI:× ' # Red
        fi
    fi
}

# Add to the beginning of your prompt by uncommenting the next line.
#PS1="\$(warn_tki)\$PS1"