Feature Request: TCP6 IPv6 Ping Ability

[titanism]

Right now we can do tcp-ping but it would be great to do tcp6-ping or tcp-ping6 using ping6 or telnet -6

[titanism]

Okay from first glance it looks like the easiest way would be to do this:

https://github.com/upptime/uptime-monitor/blob/1f97be7448c7db0e366bbebd67f87f72b220c6fc/src/update.ts#L151-L152

+const dns = require('node:dns');
+const { isIP, isIPv6 } = require('node:net');

// ...

+             const url = replaceEnvironmentVariables(site.url);
+            let address;
+            if (isIP(url)) {
+              if (site.ipv6 && !isIPv6(url)) throw new Error('Site URL must be IPv6 for ipv6 check');
+              address = url;
+            } else {
+              if (site.ipv6) address = (await dns.promises.resolve6(url))[0];
+              else address = (await dns.promises.resolve4(url))[0];
+              if (!isIP(address)) throw new Error('Site IP address could not be resolved');
+            }

          const tcpResult = await ping({
-            address: replaceEnvironmentVariables(site.url),
+            address,
            attempts: 5,
            port: Number(replaceEnvironmentVariables(site.port ? String(site.port) : "")),
          });

Then in your config change it so you do:

    - name: smtp.forwardemail.net (25)
       url: smtp.forwardemail.net
       icon: https://raw.githubusercontent.com/forwardemail/forwardemail.net/master/assets/img/favicon.ico
       port: 443
       check: "tcp-ping"
+       ipv6: true

[titanism]

We are submitting a pull request now 🎉

[titanism]

@pabio-escobar @AnandChowdhary can you please merge upptime/uptime-monitor#231?