javascript - Nodejs how to access Callback results outsite without setTimeouts? -

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• how return response asynchronous call? 24 answers

i new nodejs , javascript. learning async programming. trying find ip address domain name. using nodejs inbuild "dns" library.

dns.resolve(domainname, function onlookup(err, addresses, family) {             if (err){                 res.send(err);             } else {                  console.log(addresses);                  var domainaddress = addresses;             }         }); 

this actual code. trying domainaddress out of call back. since async programming, takes time domainaddress , unable access time.

if using code this, able access domainaddress

dns.resolve(domainname, function onlookup(err, addresses, family) {                                 if (err){                                     res.send(err);                                 } else {                                     domainaddress = addresses;                                 }                             });          settimeout(function() {           console.log(domainaddress);         }, 1000); 

but not feel right way export result callback main program.

can please give alternate solution problem ?

note: want additional task once ip. want find geo location based on ip address. need pass ip separate module called geoip-lite. since unable address outside getting difficult

function myresolve(domainname, callback){     dns.resolve(domainname, function onlookup(err, addresses, family) {             if (err){                 return callback(err);             } else {                 return callback(null, addresses);             }         }); }   myresolve(domainname, function(err, addresses){     if(err){         return res.send(err);     } else {         return res.send(addresses);     } }); 

please try code.