在golang中询问LookupTXT函数

Question

How do I change the IP address of the DNS server?

In situation, I set Google DNS server in Windows Network Settins.

And I use LookupTXT function in Golang for getting DNS txt request. But LookupTXT parameter is just the query string.

Any help or pointers would be highly appreciated. Thanks!

Answer 1

This is not straigtforward to do using golang at this point. You can however use a third party DNS package that allows configuring the resolver. First install the package:

go get github.com/bogdanovich/dns_resolver

Here is an example using it and the google resolvers 8.8.8.8 and 8.8.4.4:

package main

import (
    "log"
    "github.com/bogdanovich/dns_resolver"
)

func main() {
    resolver := dns_resolver.New([]string{"8.8.8.8", "8.8.4.4"})

    // In case of i/o timeout
    resolver.RetryTimes = 5

    ip, err := resolver.LookupHost("google.com")
    if err != nil {
        log.Fatal(err.Error())
    }
    log.Println(ip)
    // Output [216.58.192.46]
}

Source

There is an open issue in golang here, so hopefully it becomes easier to do it with the builtin net package: https://github.com/golang/go/issues/12503. It could just be a documentation problem, as it is possible now, I just can't find an example.

EDIT: actually that package only supports lookupHost: https://github.com/bogdanovich/dns_resolver/blob/master/dns_resolver.go#L51-L79

So a PR would be required to add a TXT resolver.

2nd Edit: I made a PR with txt lookup here. That project hasn't been touched in years though so it may never get accepted.