Reimplement default values (#65)

core.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"net/http"
 	"reflect"
+	"strconv"
 	"testing"
 	"time"
 )
@@ -32,51 +33,103 @@ func (r Response) CopyCommonResponse(rhs *CommonResponse) {
 	rhs.Message = r.Message
 }
 
-func getDefaultValues(v interface{}) (map[string]string, error) {
-	isNil, err := isZero(v)
-	if err != nil {
-		return make(map[string]string), err
-	}
-
-	if isNil {
-		return make(map[string]string), nil
-	}
-
-	out := make(map[string]string)
-
-	vType := reflect.TypeOf(v).Elem()
-	vValue := reflect.ValueOf(v).Elem()
+func getDefaultValues(v reflect.Value) error {
+	vValue := v.Elem()
+	vType := vValue.Type()
 
 	for i := 0; i < vType.NumField(); i++ {
 		field := vType.Field(i)
-		tag := field.Tag.Get("json")
-		defaultValue := field.Tag.Get("default")
 
-		if field.Type.Kind() == reflect.Slice {
-			// Attach any slices as query params
-			fieldVal := vValue.Field(i)
-			for j := 0; j < fieldVal.Len(); j++ {
-				out[tag] = fmt.Sprintf("%v", fieldVal.Index(j))
-			}
-		} else {
-			// Add any scalar values as query params
-			fieldVal := fmt.Sprintf("%v", vValue.Field(i))
-
-			// If no value was set by the user, use the default
-			// value specified in the struct tag.
-			if fieldVal == "" || fieldVal == "0" {
-				if defaultValue == "" {
+		switch field.Type.Kind() {
+		case reflect.Slice:
+			for j := 0; j < vValue.Field(i).Len(); j++ {
+				// skip if slice type is primitive
+				if vValue.Field(i).Index(j).Kind() != reflect.Struct {
 					continue
 				}
 
-				fieldVal = defaultValue
+				// Attach any slices as query params
+				err := getDefaultValues(vValue.Field(i).Index(j).Addr())
+				if err != nil {
+					return err
+				}
+			}
+		case reflect.String:
+			isNil, err := isZero(vValue.Field(i).Addr())
+			if err != nil {
+				return err
+			}
+			if !isNil {
+				continue
 			}
 
-			out[tag] = fmt.Sprintf("%v", fieldVal)
+			defaultValue, ok := field.Tag.Lookup("default")
+			if !ok {
+				continue
+			}
+
+			vValue.Field(i).SetString(defaultValue)
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+			isNil, err := isZero(vValue.Field(i).Addr())
+			if err != nil {
+				return err
+			}
+			if !isNil {
+				continue
+			}
+
+			defaultValue, ok := field.Tag.Lookup("default")
+			if !ok {
+				continue
+			}
+			defaultValueInt, err := strconv.Atoi(defaultValue)
+			if err != nil {
+				return err
+			}
+
+			vValue.Field(i).SetInt(int64(defaultValueInt))
+		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+			isNil, err := isZero(vValue.Field(i).Addr())
+			if err != nil {
+				return err
+			}
+			if !isNil {
+				continue
+			}
+
+			defaultValue, ok := field.Tag.Lookup("default")
+			if !ok {
+				continue
+			}
+			defaultValueUint, err := strconv.ParseUint(defaultValue, 10, 64)
+			if err != nil {
+				return err
+			}
+
+			vValue.Field(i).SetUint(uint64(defaultValueUint))
+		case reflect.Struct:
+			err := getDefaultValues(vValue.Field(i).Addr())
+			if err != nil {
+				return err
+			}
+		case reflect.Ptr:
+			isNil, err := isZero(vValue.Field(i).Addr())
+			if err != nil {
+				return err
+			}
+			if isNil {
+				continue
+			}
+
+			if err := getDefaultValues(vValue.Field(i)); err != nil {
+				return err
+			}
+		default:
+			continue
 		}
 	}
 
-	return out, nil
+	return nil
 }
 
 func buildRawQuery(req *http.Request, v interface{}) (string, error) {
@@ -86,23 +139,20 @@ func buildRawQuery(req *http.Request, v interface{}) (string, error) {
 		return query.Encode(), nil
 	}
 
-	values, err := getDefaultValues(v)
+	err := getDefaultValues(reflect.ValueOf(v))
 	if err != nil {
 		return "", err
 	}
-	for k, v := range values {
-		query.Add(k, v)
-	}
 
 	return query.Encode(), nil
 }
 
-func isZero(v interface{}) (bool, error) {
-	t := reflect.TypeOf(v)
+func isZero(v reflect.Value) (bool, error) {
+	t := v.Elem().Type()
 	if !t.Comparable() {
 		return false, fmt.Errorf("type is not comparable: %v", t)
 	}
-	return v == reflect.Zero(t).Interface(), nil
+	return reflect.Zero(t).Equal(v.Elem()), nil
 }
 
 func TimeFromString(t *testing.T, format, datetime string) time.Time {