Extract just the domain name or IP address from URL string

get_domain_from_url.sh

#!/bin/bash

get_domain_name() {
    echo "$1" | awk -F/ '{print $3}' | sed 's/:.*//'
}

URLS=$(cat <<-END
http://1.1.1.1
http://1.1.1.1:8443
https://1.1.1.1
https://1.1.1.1:8443
http://hello-world
http://hello-world.com
http://sub.hello-world.com
http://hello-world:8080
http://hello-world.com:8080
http://sub.hello-world.com:8080
https://hello-word/foo/bar
END
)

for TEST_URL in ${URLS}; do
    echo "For URL:${TEST_URL}, domain name:$(get_domain_name ${TEST_URL})"
done