package util import ( "errors" "fmt" "net/url" "reflect" "strconv" "strings" jsoniter "github.com/json-iterator/go" ) func IsSimpleType(f reflect.Value) bool { if _, ok := f.Interface().(fmt.Stringer); ok { return true } switch f.Kind() { case reflect.Bool, reflect.Int, reflect.Int64, reflect.Uint, reflect.Uint64, reflect.String: return true } return false } func SimpleTypeToParam(f reflect.Value) string { if s, ok := f.Interface().(fmt.Stringer); ok { return s.String() } switch f.Kind() { case reflect.Bool: return strconv.FormatBool(f.Bool()) case reflect.Int, reflect.Int64: // f.Int() is always an int64 return strconv.FormatInt(f.Int(), 10) case reflect.Uint, reflect.Uint64: // f.Uint() is always an uint64 return strconv.FormatUint(f.Uint(), 10) case reflect.String: return f.String() } panic("the input parameter is not a simple type") } func Changed(o interface{}, fieldName string) bool { r := reflect.ValueOf(o) value := reflect.Indirect(r).FieldByName(fieldName) return !value.IsNil() } func ToParams(o interface{}) (url.Values, error) { params := url.Values{} if o == nil || reflect.ValueOf(o).IsNil() { return params, nil } json := jsoniter.ConfigCompatibleWithStandardLibrary s := reflect.ValueOf(o) if reflect.Ptr == s.Kind() { s = s.Elem() } sType := s.Type() for i := 0; i < s.NumField(); i++ { fieldName := sType.Field(i).Name if !Changed(o, fieldName) { continue } fieldName = strings.ToLower(fieldName) f := s.Field(i) if reflect.Ptr == f.Kind() { f = f.Elem() } switch { case IsSimpleType(f): params.Set(fieldName, SimpleTypeToParam(f)) case f.Kind() == reflect.Slice: for i := 0; i < f.Len(); i++ { elem := f.Index(i) if IsSimpleType(elem) { params.Add(fieldName, SimpleTypeToParam(elem)) } else { return nil, errors.New("slices must contain only simple types") } } case f.Kind() == reflect.Map: lowerCaseKeys := make(map[string][]string) iter := f.MapRange() for iter.Next() { lowerCaseKeys[iter.Key().Interface().(string)] = iter.Value().Interface().([]string) } s, err := json.MarshalToString(lowerCaseKeys) if err != nil { return nil, err } params.Set(fieldName, s) } } return params, nil }