only return valid IPs

[remicollet]

On recent linux distro (e.g. Fedora 33+) Network Manager generates /etc/Resolv.conf with interface references

Example:

# Generated by NetworkManager
search remirepo.net
nameserver 192.168.1.1
nameserver fe80::7e94:2aff:fe85:5cce%eno1

Last address is not valid, but not filtered by loadResolvConfBlocking, so create unusable configuration
Ex: running react/socket test suite

There were 8 errors:

1) React\Tests\Socket\ConnectorTest::testConnectorUsesTcpAsDefaultScheme
InvalidArgumentException: Invalid nameserver address given

/usr/share/php/React/Dns/Query/UdpTransportExecutor.php:115
...

This trivial fix filter to only return valid IPs

[clue]

@remicollet Thank you for looking into this and filing this PR!

I've also looked into this and have just filed #187 to apply a slightly different logic. Instead of ignoring the entire nameserver entry, it will only ignore the IPv6 zone ID, so it would at least still fall back to fe80::7e94:2aff:fe85:5cce as a secondary DNS server in your case.

In either case, it will no longer throw an InvalidArgumentException and should work just fine by using the primary DNS server first.

[remicollet]

nice