frostfs-node/pkg/util/attributes/parser.go

71 lines
1.6 KiB
Go

package attributes
import (
"errors"
"fmt"
"strings"
"github.com/TrueCloudLab/frostfs-sdk-go/netmap"
)
const keyValueSeparator = ":"
// ReadNodeAttributes parses node attributes from list of string in "Key:Value" format
// and writes them into netmap.NodeInfo instance. Supports escaped symbols
// "\:", "\/" and "\\".
func ReadNodeAttributes(dst *netmap.NodeInfo, attrs []string) error {
cache := make(map[string]struct{}, len(attrs))
for i := range attrs {
line := replaceEscaping(attrs[i], false) // replaced escaped symbols with non-printable symbols
words := strings.Split(line, keyValueSeparator)
if len(words) != 2 {
return errors.New("missing attribute key and/or value")
}
_, ok := cache[words[0]]
if ok {
return fmt.Errorf("duplicated keys %s", words[0])
}
cache[words[0]] = struct{}{}
// replace non-printable symbols with escaped symbols without escape character
words[0] = replaceEscaping(words[0], true)
words[1] = replaceEscaping(words[1], true)
if words[0] == "" {
return errors.New("empty key")
} else if words[1] == "" {
return errors.New("empty value")
}
dst.SetAttribute(words[0], words[1])
}
return nil
}
func replaceEscaping(target string, rollback bool) (s string) {
const escChar = `\`
var (
oldKVSep = escChar + keyValueSeparator
oldEsc = escChar + escChar
newKVSep = string(uint8(2))
newEsc = string(uint8(3))
)
if rollback {
oldKVSep, oldEsc = newKVSep, newEsc
newKVSep = keyValueSeparator
newEsc = escChar
}
s = strings.ReplaceAll(target, oldEsc, newEsc)
s = strings.ReplaceAll(s, oldKVSep, newKVSep)
return
}