test_com
test.com:tag
test.com:5000
test.com/repo:tag
test:5000/repo
test:5000/repo:tag
test:5000/repo@sha256:ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
test:5000/repo:tag@sha256:ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
test:5000/repo
lowercase:Uppercase
a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a/a:tag-puts-this-over-max
sub-dom1.foo.com/bar/baz/quux
sub-dom1.foo.com/bar/baz/quux:some-long-tag
b.gcr.io/test.example.com/my-app:test.example.com
xn--n3h.com/myimage:xn--n3h.com
xn--7o8h.com/myimage:xn--7o8h.com@sha512:ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
foo_bar.com:8080
foo/foo_bar.com:8080
192.168.1.1
192.168.1.1:tag
192.168.1.1:5000
192.168.1.1/repo
192.168.1.1:5000/repo
192.168.1.1:5000/repo:5050
[2001:db8::1]/repo
[2001:db8:1:2:3:4:5:6]/repo:tag
[2001:db8::1]:5000/repo
[2001:db8::1]:5000/repo:tag
[2001:db8::1]:5000/repo@sha256:ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
[2001:db8::1]:5000/repo:tag@sha256:ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
[2001:db8::]:5000/repo
[::1]:5000/repo