in model/relabel/relabel.go [102:153]
func (c *Config) UnmarshalYAML(unmarshal func(interface{}) error) error {
*c = DefaultRelabelConfig
type plain Config
if err := unmarshal((*plain)(c)); err != nil {
return err
}
if c.Regex.Regexp == nil {
c.Regex = MustNewRegexp("")
}
if c.Action == "" {
return fmt.Errorf("relabel action cannot be empty")
}
if c.Modulus == 0 && c.Action == HashMod {
return fmt.Errorf("relabel configuration for hashmod requires non-zero modulus")
}
if (c.Action == Replace || c.Action == HashMod || c.Action == Lowercase || c.Action == Uppercase || c.Action == KeepEqual || c.Action == DropEqual) && c.TargetLabel == "" {
return fmt.Errorf("relabel configuration for %s action requires 'target_label' value", c.Action)
}
if (c.Action == Replace || c.Action == Lowercase || c.Action == Uppercase || c.Action == KeepEqual || c.Action == DropEqual) && !relabelTarget.MatchString(c.TargetLabel) {
return fmt.Errorf("%q is invalid 'target_label' for %s action", c.TargetLabel, c.Action)
}
if (c.Action == Lowercase || c.Action == Uppercase || c.Action == KeepEqual || c.Action == DropEqual) && c.Replacement != DefaultRelabelConfig.Replacement {
return fmt.Errorf("'replacement' can not be set for %s action", c.Action)
}
if c.Action == LabelMap && !relabelTarget.MatchString(c.Replacement) {
return fmt.Errorf("%q is invalid 'replacement' for %s action", c.Replacement, c.Action)
}
if c.Action == HashMod && !model.LabelName(c.TargetLabel).IsValid() {
return fmt.Errorf("%q is invalid 'target_label' for %s action", c.TargetLabel, c.Action)
}
if c.Action == DropEqual || c.Action == KeepEqual {
if c.Regex != DefaultRelabelConfig.Regex ||
c.Modulus != DefaultRelabelConfig.Modulus ||
c.Separator != DefaultRelabelConfig.Separator ||
c.Replacement != DefaultRelabelConfig.Replacement {
return fmt.Errorf("%s action requires only 'source_labels' and `target_label`, and no other fields", c.Action)
}
}
if c.Action == LabelDrop || c.Action == LabelKeep {
if c.SourceLabels != nil ||
c.TargetLabel != DefaultRelabelConfig.TargetLabel ||
c.Modulus != DefaultRelabelConfig.Modulus ||
c.Separator != DefaultRelabelConfig.Separator ||
c.Replacement != DefaultRelabelConfig.Replacement {
return fmt.Errorf("%s action requires only 'regex', and no other fields", c.Action)
}
}
return nil
}