Repository navigation
Add version of dns.lookup that returns all results #736
Description
Activity
This seems like a pretty simple addition. I'd be fine with working on it, if others find it useful. I think the window is currently open for a minor version bump too.
This seems like a perfectly reasonable addition to me. It doesn't even need a new function;
dns.lookup()already looks up all the addresses but it's intentionally crippled to only report the first one. We can simply extend it like this:dns.lookup('google.com', { all: true }, function(err, addrs) { /* ... */ }); // strawman
The callback gets the address family as its third argument now. For the
{ all: true }case, we probably want to drop that and report the family in theaddrsarray. It's a list of strings now, that would have to change to a list of objects.I'll start working on this according to @bnoordhuis's proposal, if that's ok with you, @cjihrig.
@silverwind sure. I was thinking you might just want to change this line to point to another function. And the callback would change from
function(err, address, family)tofunction(err, addresses), where each element inaddresseswould be something like{ip: '127.0.0.1', family: 4}.My first approach would've been to modify
onlookupwith additional logic and add areq.allproperty. You think that a second function would be cleaner?I figured it would be simpler, with less chance of breaking existing code, to just point to a new function. The two functions will have very little overlap except checking for an error.
True, I'll add an second function then, definitely safer.
Any opinions if the address field in the object should be called
addressorip? I'm leaning more towardsaddressfor correctness, but @cjihrig suggestedip. Also, the docs usually call itaddress.FWIW, I don't have a strong opinion. I just thought
addresses.addressseemed a little odd.We call it
addressin most other places, e.g.socket.address().address.I'll put this up shortly for a PR, just have to test on OS X, as apparently my Windows machine isn't able to
dns.lookupfor an IPv6 (gettingENOENT), butdns.resolve6strangely works. This is onv1.xtoo. Might be a separate issue.- added a commit that references this issue
on Feb 6, 2015
The
dnsmodule provides two sets of methods: theresolvefamily, which directly resolves using the DNS protocol, and thelookupfunction, which uses the system resolver (throughgetaddrinfo) and returns at most one address.It's often preferable to use the system resolver, since it can use things like mDNS. However, using the
dns.lookupAPI makes it impossible to receive multiple IP addresses in response to a DNS query (See #708 for motivating example).Proposal: Add a new function
dns.lookupAllthat behaves likedns.lookup, but returns all addresses given bygetaddrinfo.