Pre-receive hook to validate user and email fields on git commits

pre-receive

#!/bin/bash
AUTHORINFO=$(git var GIT_AUTHOR_IDENT) || exit 1
NAME=$(printf '%s\n' "${AUTHORINFO}" | sed -n 's/^\(.*\) <.*$/\1/p')
EMAIL=$(printf '%s\n' "${AUTHORINFO}" | sed -n 's/^.* <\(.*\)> .*$/\1/p')
HOSTNAME=$(hostname -f)

if [ "$NAME" != "$USER" ]
then
        echo "YOUR COMMIT(S) HAVE NOT BEEN ACCEPTED"
        echo ""
        echo "Sorry! Please fix your username before you send changes to $HOSTNAME"
        echo ""
        echo "Use the following command on a terminal to update it:"
        echo '    git config --global user.name "'$USER'"'

        exit 1
fi

VALIDEMAIL='@valid.domain.com'
if [[ "$EMAIL" != *"$VALIDEMAIL"* ]]
then
        echo "YOUR COMMIT(S) HAVE NOT BEEN ACCEPTED"
        echo ""
        echo "Sorry! Please use your $VALIDEMAIL email account to sent changes to $HOSTNAME"
        echo ""
        echo "Use the following command on a terminal to update it:"
        echo '    git config --global user.email "youremailaddresshere@domain.com"'

        exit 1
fi

Only works if SSH/local commit because web is authenticated differently.