createResolver broken in master branch

createResolver is broken in master branch

If i want to resolve a dns attribute using the current master branch, it throw this error :

/code/eviltik/node-dns/index.js:46
      const resolve = createResolver({ dns: address, port });
                      ^

TypeError: createResolver is not a function
    at /code/eviltik/node-dns/index.js:46:23
    at Array.map (<anonymous>)
    at DNS.query (/code/eviltik/node-dns/index.js:45:37)
    at DNS.resolve (/code/eviltik/node-dns/index.js:57:17)
    at DNS.resolveCNAME (/code/eviltik/node-dns/index.js:69:17)
    .....

CreateResolver is created here https://github.com/song940/node-dns/blob/182d88e2c68394ea480063dbaf3f1409c50cf625/index.js#L39

Everything was OK before DoH Server implementation (https://github.com/song940/node-dns/pull/26) https://github.com/song940/node-dns/blob/452ab97d94f06d78fa715715e5af953eca547e95/index.js#L76-L79

After DoH Server implementation, no more udp client by default https://github.com/song940/node-dns/blob/182d88e2c68394ea480063dbaf3f1409c50cf625/index.js#L79-L82

Except if i’m missing something, we have no option to choose which Client we want (DOH, TCP, UDP, Google) to use for resolver.

I’d like to suggest a new config option for solve it, but not sure it’s the way to go : a new config option and a code change

const Dns2 = require('dns2');
const dns2 = new Dns2({
   resolverProtocol:'UDP' // or TCP, DOH, Google
});

I’d like to purpose a PR, but my coding style does not match with the current one.

In the idea :

class DNS extends EventEmitter {
  constructor(options) {
    super();
    Object.assign(this, {
      port: 53,
      resolverProtocol:'UDP' // new option
      ...........................
      
 ---------------------------
 
query(name, type, cls, clientIp) {
    const { port, nameServers, resolverProtocol } = this;
    
    // Choose the good Client
    
    if (resolverProtocol === 'TCP') {
         const{ ClientUDP: createResolver } = DNS;
    } else if (resolverProtocol === 'TCP') {
       const{ ClientTCP: createResolver } = DNS;
    } .......
 

@DSorlov, @song940, what do you think ?

Thank you

[song940]

Mhh. The fix make make the resolver as UDP by default, like before DSorlov DOH implementation. So yes, it’s fixed.

But the users of this library cannot choose another protocol for the resolver, with a config option. Or i’m missing something.

resolverProtocol assign to instance in constructor, users can pass resolverProtocol to options.

 const { port, nameServers, resolverProtocol = 'UDP' } = this;

It means resolverProtocol use UDP when resolverProtocol not exists. but most cases it not be happen.

[DSorlov]

I would agree that the newer coding style should replace. This was obviously broken in my push and should be remedied by modernizing the code imho.