Oscar Zhou
62 lines
1.7 KiB
Go
62 lines
1.7 KiB
Go
package validation
|
|
|
|
// borrowed from apimachinery@v0.17.2/pkg/util/validation/validation.go
|
|
// https://github.com/kubernetes/kubernetes/blob/master/staging/src/k8s.io/apimachinery/pkg/util/validation/validation.go
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"regexp"
|
|
"strings"
|
|
)
|
|
|
|
const dns1123LabelFmt string = "[a-z0-9]([-a-z0-9]*[a-z0-9])?"
|
|
const dns1123SubdomainFmt string = dns1123LabelFmt + "(\\." + dns1123LabelFmt + ")*"
|
|
const DNS1123SubdomainMaxLength int = 253
|
|
|
|
var dns1123SubdomainRegexp = regexp.MustCompile("^" + dns1123SubdomainFmt + "$")
|
|
|
|
// IsDNS1123Subdomain tests for a string that conforms to the definition of a subdomain in DNS (RFC 1123).
|
|
func IsDNS1123Subdomain(value string) error {
|
|
var errs error
|
|
if len(value) > DNS1123SubdomainMaxLength {
|
|
errs = errors.Join(errs, MaxLenError(DNS1123SubdomainMaxLength))
|
|
}
|
|
if !dns1123SubdomainRegexp.MatchString(value) {
|
|
errs = errors.Join(errs, RegexError(dns1123SubdomainFmt, "example.com"))
|
|
}
|
|
return errs
|
|
}
|
|
|
|
// MaxLenError returns a string explanation of a "string too long" validation failure.
|
|
func MaxLenError(length int) error {
|
|
return fmt.Errorf("must be no more than %d characters", length)
|
|
}
|
|
|
|
// RegexError returns a string explanation of a regex validation failure.
|
|
func RegexError(fmt string, examples ...string) error {
|
|
var s strings.Builder
|
|
|
|
_, _ = s.WriteString("must match the regex ")
|
|
_, _ = s.WriteString(fmt)
|
|
|
|
if len(examples) == 0 {
|
|
return errors.New(s.String())
|
|
}
|
|
|
|
s.WriteString(" (e.g. ")
|
|
for i := range examples {
|
|
if i > 0 {
|
|
_, _ = s.WriteString(" or ")
|
|
}
|
|
|
|
_, _ = s.WriteRune('\'')
|
|
_, _ = s.WriteString(examples[i])
|
|
_, _ = s.WriteRune('\'')
|
|
}
|
|
|
|
_, _ = s.WriteRune(')')
|
|
|
|
return errors.New(s.String())
|
|
}
|