packer-cn/builder/googlecompute/template_funcs.go

45 lines
789 B
Go

package googlecompute
import (
"regexp"
"strings"
"text/template"
)
func isalphanumeric(b byte) bool {
if '0' <= b && b <= '9' {
return true
}
if 'a' <= b && b <= 'z' {
return true
}
return false
}
// Clean up image name by replacing invalid characters with "-"
// truncate up to 63 length, convert to a lower case
func templateCleanImageName(s string) string {
re := regexp.MustCompile(`^[a-z][-a-z0-9]{0,61}[a-z0-9]$`)
if re.MatchString(s) {
return s
}
b := []byte(strings.ToLower(s))
l := 63
if len(b) < 63 {
l = len(b)
}
newb := make([]byte, l)
for i := range newb {
if isalphanumeric(b[i]) {
newb[i] = b[i]
} else {
newb[i] = '-'
}
}
return string(newb)
}
var TemplateFuncs = template.FuncMap{
"clean_image_name": templateCleanImageName,
}