📨 Validate an email address in Go

mail

An email address in Golang can be validated using the standard library function mail.ParseAddress. This function parses an RFC 5322 address, but by using it appropriately, we can also check if a string is a valid email address and get it from the "name <local-part@domain>" format.

package main

import (
    "fmt"
    "net/mail"
)

func validMailAddress(address string) (string, bool) {
    addr, err := mail.ParseAddress(address)
    if err != nil {
        return "", false
    }
    return addr.Address, true
}

var addresses = []string{
    "foo@gmail.com",
    "Gopher <from@example.com>",
    "example",
}

func main() {
    for _, a := range addresses {
        if addr, ok := validMailAddress(a); ok {
            fmt.Printf("value: %-30s valid email: %-10t address: %s\n", a, ok, addr)
        } else {
            fmt.Printf("value: %-30s valid email: %-10t\n", a, ok)
        }
    }
}

Output:

value: foo@gmail.com                  valid email: true       address: foo@gmail.com
value: Gopher <from@example.com>      valid email: true       address: from@example.com
value: example                        valid email: false