feat: refactor reflections utilities as per v3

Author: sranka

api/query.go

@@ -289,22 +289,6 @@ func checkParamsType(p interface{}) error {
 	return nil
 }
 
-// getFieldType extracts type of value
-func getFieldType(v reflect.Value) reflect.Type {
-	t := v.Type()
-	if t.Kind() == reflect.Ptr {
-		t = t.Elem()
-		v = v.Elem()
-	}
-	if t.Kind() == reflect.Interface && !v.IsNil() {
-		t = reflect.ValueOf(v.Interface()).Type()
-	}
-	return t
-}
-
-// timeType is the exact type for the Time
-var timeType = reflect.TypeOf(time.Time{})
-
 // validParamType validates that t is primitive type or string or interface
 func validParamType(t reflect.Type) bool {
 	return (t.Kind() > reflect.Invalid && t.Kind() < reflect.Complex64) ||

api/reflection.go

@@ -0,0 +1,72 @@
+package api
+
+import (
+	"fmt"
+	"reflect"
+	"time"
+)
+
+// checkContainerType validates the value is struct with simple type fields
+// or a map with key as string and value as a simple type
+func checkContainerType(p interface{}, alsoMap bool, usage string) error {
+	if p == nil {
+		return nil
+	}
+	t := reflect.TypeOf(p)
+	v := reflect.ValueOf(p)
+	if t.Kind() == reflect.Ptr {
+		t = t.Elem()
+		v = v.Elem()
+	}
+	if t.Kind() != reflect.Struct && (!alsoMap || t.Kind() != reflect.Map) {
+		return fmt.Errorf("cannot use %v as %s", t, usage)
+	}
+	switch t.Kind() {
+	case reflect.Struct:
+		fields := reflect.VisibleFields(t)
+		for _, f := range fields {
+			fv := v.FieldByIndex(f.Index)
+			t := getFieldType(fv)
+			if !validFieldType(t) {
+				return fmt.Errorf("cannot use field '%s' of type '%v' as a %s", f.Name, t, usage)
+			}
+
+		}
+	case reflect.Map:
+		key := t.Key()
+		if key.Kind() != reflect.String {
+			return fmt.Errorf("cannot use map key of type '%v' for %s name", key, usage)
+		}
+		for _, k := range v.MapKeys() {
+			f := v.MapIndex(k)
+			t := getFieldType(f)
+			if !validFieldType(t) {
+				return fmt.Errorf("cannot use map value type '%v' as a %s", t, usage)
+			}
+		}
+	}
+	return nil
+}
+
+// getFieldType extracts type of value
+func getFieldType(v reflect.Value) reflect.Type {
+	t := v.Type()
+	if t.Kind() == reflect.Ptr {
+		t = t.Elem()
+		v = v.Elem()
+	}
+	if t.Kind() == reflect.Interface && !v.IsNil() {
+		t = reflect.ValueOf(v.Interface()).Type()
+	}
+	return t
+}
+
+// timeType is the exact type for the Time
+var timeType = reflect.TypeOf(time.Time{})
+
+// validFieldType validates that t is primitive type or string or interface
+func validFieldType(t reflect.Type) bool {
+	return (t.Kind() > reflect.Invalid && t.Kind() < reflect.Complex64) ||
+		t.Kind() == reflect.String ||
+		t == timeType
+}