在“ crypto / rand”成功之前生成随机字符串是个好主意吗？

Is it a good idea to generate a secure random hex string until the process succeeds?

All examples I've come across show that if rand.Read returns error, we should panic, os.Exit(1) or return empty string and the error.

I need my program to continue to function in case of such errors and wait until a random string is generated. Is it a good idea to loop until the string is generated, any pitfalls with that?

import "crypto/rand"

func RandomHex() string {
    var buf [16]byte
    for {
        _, err := rand.Read(buf[:])
        if err == nil {
            break
        }
    }
    return hex.EncodeToString(buf[:])
}

Is it a good idea to loop until the string is generated,

That depends. Probably yes.

any pitfalls with that?

You discard the random bytes read on error. And this in a tight loop. This may drain you entropy source (depending on the OS) faster than it can be filled.

Instead of an unbound infinite loop: Break after n rounds and give up. Graceful degradation or stopping is best: If your program is stuck in an endless loop it is also not "continue"ing.

No. It may always return an error in certain contexts.

Example: playground: don't use /dev/urandom in crypto/rand

Imagine that a machine does not have the source that crypto/rand gets data from or the program runs in a context that doesn't have access to that source. In that case you might consider having the program return that error in a meaningful way rather than spin.

More explicitly, if you are serious in your use of crypto/rand then consider writing RandomHex such that it is exceptionally clear to the caller that it is meant for security contexts (possibly rename it) and return the error from RandomHex. The calling function needs to handle that error and let the user know that something is very wrong. For example in a rest api, I'd expect that error to surface to the request handler, fail & return a 500 at that point, and log a high severity error.