Does Go's DNS Resolution Feature Cache Lookups?

The Go programming language's standard library lacks a built-in mechanism for caching DNS lookups through dnsclient. While caching DNS responses can significantly enhance the efficiency of an application by reducing the number of expensive DNS queries, Go does not currently offer this feature.

Alternative Caching Solutions

Since Go does not provide native DNS caching, developers can explore external packages to implement the functionality. One such package is "dnscache," which offers a robust solution for DNS caching.

By integrating "dnscache" with Go's HTTP transport, as demonstrated in the provided code snippet:

http.DefaultClient.Transport = &http.Transport {
  MaxIdleConnsPerHost: 64,
  Dial: func(network string, address string) (net.Conn, error) {
    separator := strings.LastIndex(address, ":")
    ip, _ := dnscache.FetchString(address[:separator])
    return net.Dial("tcp", ip   address[separator:])
  },
}

It becomes possible to enable DNS caching across all HTTP requests initiated via http.Get and other related functions. This approach can effectively reduce the overhead of DNS lookups and improve the performance of applications that rely heavily on DNS-based interactions.