portainer/api/kubernetes/validation/validation.go

49 lines
1.4 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 (
"fmt"
"regexp"
)
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) []string {
var errs []string
if len(value) > DNS1123SubdomainMaxLength {
errs = append(errs, MaxLenError(DNS1123SubdomainMaxLength))
}
if !dns1123SubdomainRegexp.MatchString(value) {
errs = append(errs, RegexError(dns1123SubdomainFmt, "example.com"))
}
return errs
}
// MaxLenError returns a string explanation of a "string too long" validation failure.
func MaxLenError(length int) string {
return fmt.Sprintf("must be no more than %d characters", length)
}
// RegexError returns a string explanation of a regex validation failure.
func RegexError(fmt string, examples ...string) string {
s := "must match the regex " + fmt
if len(examples) == 0 {
return s
}
s += " (e.g. "
for i := range examples {
if i > 0 {
s += " or "
}
s += "'" + examples[i] + "'"
}
return s + ")"
}