http.request option "family: 6" doesn't enable request over IPv6

[DimitryDushkin]

• Version: 5.5
• Platform: Ubuntu 14.04.1
• Subsystem: http(s)

Seems like family option does nothing with actual DNS resolve to ipv6.
Problem is internal server should only use ipv6. So, instead of

https.get({
    hostname: 'cloud-api.yandex.net',
    path: '/v1/disk/resources?path=/',
    family: 6,
    port: 443,
    protocol: 'https:'
}, (res) => {
    console.log(res);
}).on('error', (e) => {
  console.log(`Got error: ${e.message}`);    // Got error: connect EHOSTUNREACH 213.180.204.127:443
});

i should write

dns.lookup('cloud-api.yandex.net', { family: 6 }, (err, addr, family) => {
    https.get({
        hostname: addr,
        path: '/v1/disk/resources?path=/',
        port: 443,
        protocol: 'https:',
        headers: { host: 'cloud-api.yandex.net' }
    }, (res) => {
        console.log(res);
    }).on('error', (e) => {
      console.log(`Got error: ${e.message}`);
    });
});

[bnoordhuis]

Confirmed. The bug is in tls.connect() with a second-order bug in http.Agent#getName(). This patch should fix it:

diff --git a/lib/_http_agent.js b/lib/_http_agent.js
index fd74daa..3f3d148 100644
--- a/lib/_http_agent.js
+++ b/lib/_http_agent.js
@@ -102,6 +102,10 @@ Agent.prototype.getName = function(options) {
   if (options.localAddress)
     name += options.localAddress;

+  name += ':';
+  if (options.family === 4 || options.family === 6)
+    name += options.family;
+
   return name;
 };

diff --git a/lib/_tls_wrap.js b/lib/_tls_wrap.js
index 029d9ac..d42f855 100644
--- a/lib/_tls_wrap.js
+++ b/lib/_tls_wrap.js
@@ -1021,6 +1021,7 @@ exports.connect = function(/* [port, host], options, cb */) {
       connect_opt = {
         port: options.port,
         host: options.host,
+        family: options.family,
         localAddress: options.localAddress
       };
     }

[JungMinu]

@bnoordhuis would you mind if I make a PR to resolve this issue based on your comment?

[bnoordhuis]

I will but I haven't had time yet to write a robust regression test.

[bnoordhuis]

#6654