package config import ( "os" "regexp" "strconv" "time" "github.com/pkg/errors" "gopkg.in/yaml.v3" ) var reVar = regexp.MustCompile(`^\${(\w+)}$`) type InterpolatedString string func (is *InterpolatedString) UnmarshalYAML(value *yaml.Node) error { var str string if err := value.Decode(&str); err != nil { return errors.WithStack(err) } if match := reVar.FindStringSubmatch(str); len(match) > 0 { *is = InterpolatedString(os.Getenv(match[1])) } else { *is = InterpolatedString(str) } return nil } type InterpolatedInt int func (ii *InterpolatedInt) UnmarshalYAML(value *yaml.Node) error { var str string if err := value.Decode(&str); err != nil { return errors.Wrapf(err, "could not decode value '%v' (line '%d') into string", value.Value, value.Line) } if match := reVar.FindStringSubmatch(str); len(match) > 0 { str = os.Getenv(match[1]) } intVal, err := strconv.ParseInt(str, 10, 32) if err != nil { return errors.Wrapf(err, "could not parse int '%v', line '%d'", str, value.Line) } *ii = InterpolatedInt(int(intVal)) return nil } type InterpolatedBool bool func (ib *InterpolatedBool) UnmarshalYAML(value *yaml.Node) error { var str string if err := value.Decode(&str); err != nil { return errors.Wrapf(err, "could not decode value '%v' (line '%d') into string", value.Value, value.Line) } if match := reVar.FindStringSubmatch(str); len(match) > 0 { str = os.Getenv(match[1]) } boolVal, err := strconv.ParseBool(str) if err != nil { return errors.Wrapf(err, "could not parse bool '%v', line '%d'", str, value.Line) } *ib = InterpolatedBool(boolVal) return nil } type InterpolatedMap map[string]interface{} func (im *InterpolatedMap) UnmarshalYAML(value *yaml.Node) error { var data map[string]interface{} if err := value.Decode(&data); err != nil { return errors.Wrapf(err, "could not decode value '%v' (line '%d') into map", value.Value, value.Line) } for key, value := range data { strVal, ok := value.(string) if !ok { continue } if match := reVar.FindStringSubmatch(strVal); len(match) > 0 { strVal = os.Getenv(match[1]) } data[key] = strVal } *im = data return nil } type InterpolatedStringSlice []string func (iss *InterpolatedStringSlice) UnmarshalYAML(value *yaml.Node) error { var data []string if err := value.Decode(&data); err != nil { return errors.Wrapf(err, "could not decode value '%v' (line '%d') into map", value.Value, value.Line) } for index, value := range data { if match := reVar.FindStringSubmatch(value); len(match) > 0 { value = os.Getenv(match[1]) } data[index] = value } *iss = data return nil } type InterpolatedDuration time.Duration func (id *InterpolatedDuration) UnmarshalYAML(value *yaml.Node) error { var str string if err := value.Decode(&str); err != nil { return errors.Wrapf(err, "could not decode value '%v' (line '%d') into string", value.Value, value.Line) } if match := reVar.FindStringSubmatch(str); len(match) > 0 { str = os.Getenv(match[1]) } duration, err := time.ParseDuration(str) if err != nil { return errors.Wrapf(err, "could not parse duration '%v', line '%d'", str, value.Line) } *id = InterpolatedDuration(duration) return nil } func (id *InterpolatedDuration) MarshalYAML() (interface{}, error) { duration := time.Duration(*id) return duration.String(), nil } func NewInterpolatedDuration(d time.Duration) *InterpolatedDuration { id := InterpolatedDuration(d) return &id }