Bash function to automate MFA for interactive awscli usage

mfa_wrap.sh

# To use this wrapper,
#     $ . ./mfa_wrap.sh
#     $ mfa_wrap 123456 'aws s3 ls'

mfa_wrap() {
    MFA_TOKEN="$1"
    shift
    SHELL_CMD=$(aws sts get-session-token \
        --serial-number="${AWS_MFA_SERIAL?AWS_MFA_SERIAL must be set}" \
        --token-code=${MFA_TOKEN} \
        --output=text | awk '
        {
            print "export AWS_ACCESS_KEY_ID=" $2 "; "
            print "export AWS_SECRET_ACCESS_KEY=" $4 "; "
            print "export AWS_SESSION_TOKEN=" $5 "; "
            print "export AWS_SECURITY_TOKEN=" $5 "; "
        }' && echo "$@")
    bash <<<"$SHELL_CMD"
}