cm

Former-commit-id: 8f99121b81dc76c04d5910117885d9286873f26c

mvc2/binder_in_service.go

@@ -0,0 +1,81 @@
+package mvc2
+
+import (
+	"reflect"
+)
+
+type serviceFieldBinder struct {
+	Index  []int
+	Binder *InputBinder
+}
+
+func getServicesBinderForStruct(binders []*InputBinder, typ reflect.Type) func(elem reflect.Value) {
+	fields := lookupFields(typ, -1)
+	var validBinders []*serviceFieldBinder
+
+	for _, b := range binders {
+		for _, f := range fields {
+			if b.BinderType != serviceType {
+				continue
+			}
+			if equalTypes(b.BindType, f.Type) {
+				validBinders = append(validBinders,
+					&serviceFieldBinder{Index: f.Index, Binder: b})
+			}
+		}
+
+	}
+
+	if len(validBinders) == 0 {
+		return func(_ reflect.Value) {}
+	}
+
+	return func(elem reflect.Value) {
+		for _, b := range validBinders {
+			elem.FieldByIndex(b.Index).Set(b.Binder.BindFunc(nil))
+		}
+	}
+}
+
+// MustMakeServiceInputBinder calls the `MakeServiceInputBinder` and returns its first result, see its docs.
+// It panics on error.
+func MustMakeServiceInputBinder(service interface{}) *InputBinder {
+	s, err := MakeServiceInputBinder(service)
+	if err != nil {
+		panic(err)
+	}
+	return s
+}
+
+// MakeServiceInputBinder uses a difference/or strange approach,
+// we make the services as bind functions
+// in order to keep the rest of the code simpler, however we have
+// a performance penalty when calling the function instead
+// of just put the responsible service to the certain handler's input argument.
+func MakeServiceInputBinder(service interface{}) (*InputBinder, error) {
+	if service == nil {
+		return nil, errNil
+	}
+
+	var (
+		val = reflect.ValueOf(service)
+		typ = val.Type()
+	)
+
+	if !goodVal(val) {
+		return nil, errBad
+	}
+
+	if indirectTyp(typ).Kind() != reflect.Struct {
+		// if the pointer's struct is not a struct then return err bad.
+		return nil, errBad
+	}
+
+	return &InputBinder{
+		BinderType: serviceType,
+		BindType:   typ,
+		BindFunc: func(_ []reflect.Value) reflect.Value {
+			return val
+		},
+	}, nil
+}