Update to 8.4.0 | New macro type, new high-optimized MVC features. Read HISTORY.md

Former-commit-id: b72a23ba063be60a9750c8b1b0df024b0c8ed549

mvc/activator/persistence/persistence.go

@@ -0,0 +1,60 @@
+package persistence
+
+import (
+	"reflect"
+
+	"github.com/kataras/iris/mvc/activator/field"
+)
+
+// Controller is responsible to load from the original
+// end-developer's main controller's value
+// and re-store the persistence data by scanning the original.
+// It stores and sets to each new controller
+// the optional data  that should be shared among all requests.
+type Controller struct {
+	fields []field.Field
+}
+
+// Load scans and load for persistence data based on the `iris:"persistence"` tag.
+//
+// The type is the controller's Type.
+// the "val" is the original end-developer's controller's Value.
+// Returns nil if no persistence data to store found.
+func Load(typ reflect.Type, val reflect.Value) *Controller {
+	matcher := func(elemField reflect.StructField) bool {
+		if tag, ok := elemField.Tag.Lookup("iris"); ok {
+			if tag == "persistence" {
+				return true
+			}
+		}
+		return false
+	}
+
+	handler := func(f *field.Field) {
+		valF := val.Field(f.Index)
+		if valF.IsValid() || (valF.Kind() == reflect.Ptr && !valF.IsNil()) {
+			val := reflect.ValueOf(valF.Interface())
+			if val.IsValid() || (val.Kind() == reflect.Ptr && !val.IsNil()) {
+				f.Value = val
+			}
+		}
+	}
+
+	fields := field.LookupFields(typ.Elem(), matcher, handler)
+
+	if len(fields) == 0 {
+		return nil
+	}
+
+	return &Controller{
+		fields: fields,
+	}
+}
+
+// Handle re-stores the persistence data at the current controller.
+func (pc *Controller) Handle(c reflect.Value) {
+	elem := c.Elem() // controller should always be a pointer at this state
+	for _, f := range pc.fields {
+		f.SendTo(elem)
+	}
+}