How to validate an email address in Golang

I have checked StackOverflow and couldn't find any question that answers "how do I validate an email address in Go?".

After some research, I solved it to fill my need.

I have this regex and function in Go, which work fine:

import (
    "fmt"
    "regexp"
)

func main() {
    fmt.Println(isEmailValid("test44@gmail.com")) // true
    fmt.Println(isEmailValid("test$@gmail.com")) // true -- expected "false" 
}


// isEmailValid checks if the email provided is valid by regex.
func isEmailValid(e string) bool {
    emailRegex := regexp.MustCompile("^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$")
    return emailRegex.MatchString(e)
}

The problem is that it allows special characters that I don't want. I tried to use some from other languages' regex expression, but it throws the error "unknown escape" in debug.

Could anyone correct my regex or suggest another Go module?

The standard lib has email parsing and validation built in, simply use: mail.ParseAddress().

A simple "is-valid" test:

func valid(email string) bool {
    _, err := mail.ParseAddress(email)
    return err == nil
}

Testing it:

for _, email := range []string{
    "good@exmaple.com",
    "bad-example",
} {
    fmt.Printf("%18s valid: %t\n", email, valid(email))
}

Which outputs (try it on the Go Playground):

  good@exmaple.com valid: true
       bad-example valid: false

NOTE:

The net/mail package implements and follows the RFC 5322 specification (and extension by RFC 6532). This means a seemingly bad email address like bad-example@t is accepted and parsed by the package because it's valid according to the spec. t may be a valid local domain name, it does not necessarily have to be a public domain. net/mail does not check if the domain part of the address is a public domain, nor that it is an existing, reachable public domain.