Properly check url and email address

person.go

@@ -4,6 +4,8 @@ import (
 	"encoding/xml"
 	"errors"
 	"fmt"
+	"net/mail"
+	"net/url"
 )
 
 type Person struct {
@@ -27,6 +29,18 @@ func (p *Person) Check() error {
 		return errors.New("name element of person element empty")
 	}
 
+	if p.URI != "" {
+		if _, err := url.ParseRequestURI(string(p.URI)); err != nil {
+			return fmt.Errorf("email element of person %v not correctly formatted", p.Name)
+		}
+	}
+
+	if p.Email != "" {
+		if _, err := mail.ParseAddress(string(p.Email)); err != nil {
+			return fmt.Errorf("email element of person %v not correctly formatted", p.Name)
+		}
+	}
+
 	if p.Extensions != nil {
 		for i, e := range p.Extensions {
 			if err := e.Check(); err != nil {