Add status code 103 Early Hints. Add the ability to customize and change the order of controller's fields and their registered valid dependencies relative to: #1343

Former-commit-id: 5bd9e02e5fafca135d17cad87f4a9aec526b333b

mvc/controller.go

@@ -86,6 +86,7 @@ type ControllerActivator struct {
 	// Can be bind-ed to the the new controller's fields and method that is fired
 	// on incoming requests.
 	dependencies di.Values
+	sorter       di.Sorter
 
 	errorHandler hero.ErrorHandler
 
@@ -108,7 +109,7 @@ func NameOf(v interface{}) string {
 	return fullname
 }
 
-func newControllerActivator(router router.Party, controller interface{}, dependencies []reflect.Value, errorHandler hero.ErrorHandler) *ControllerActivator {
+func newControllerActivator(router router.Party, controller interface{}, dependencies []reflect.Value, sorter di.Sorter, errorHandler hero.ErrorHandler) *ControllerActivator {
 	typ := reflect.TypeOf(controller)
 
 	c := &ControllerActivator{
@@ -128,6 +129,7 @@ func newControllerActivator(router router.Party, controller interface{}, depende
 		routes: whatReservedMethods(typ),
 		// CloneWithFieldsOf: include the manual fill-ed controller struct's fields to the dependencies.
 		dependencies: di.Values(dependencies).CloneWithFieldsOf(controller),
+		sorter:       sorter,
 		errorHandler: errorHandler,
 	}
 
@@ -386,7 +388,14 @@ var emptyIn = []reflect.Value{}
 
 func (c *ControllerActivator) attachInjector() {
 	if c.injector == nil {
-		c.injector = di.Struct(c.Value, c.dependencies...)
+		c.injector = di.MakeStructInjector(
+			di.ValueOf(c.Value),
+			di.DefaultHijacker,
+			di.DefaultTypeChecker,
+			c.sorter,
+			di.Values(c.dependencies).CloneWithFieldsOf(c.Value)...,
+		)
+		// c.injector = di.Struct(c.Value, c.dependencies...)
 		if !c.servesWebsocket {
 			golog.Debugf("MVC Controller [%s] [Scope=%s]", c.fullName, c.injector.Scope)
 		} else {

mvc/mvc.go

@@ -39,7 +39,12 @@ var HeroDependencies = true
 //
 // See `mvc#New` for more.
 type Application struct {
-	Dependencies         di.Values
+	Dependencies di.Values
+	// Sorter is a `di.Sorter`, can be used to customize the order of controller's fields
+	// and their available bindable values to set.
+	// Sorting matters only when a field can accept more than one registered value.
+	// Defaults to nil; order of registration matters when more than one field can accept the same value.
+	Sorter               di.Sorter
 	Router               router.Party
 	Controllers          []*ControllerActivator
 	websocketControllers []websocket.ConnHandler
@@ -129,6 +134,15 @@ Set the Logger's Level to "debug" to view the active dependencies per controller
 	return app
 }
 
+// SortByNumMethods is the same as `app.Sorter = di.SortByNumMethods` which
+// prioritize fields and their available values (only if more than one)
+// with the highest number of methods,
+// this way an empty interface{} is getting the "thinnest" available value.
+func (app *Application) SortByNumMethods() *Application {
+	app.Sorter = di.SortByNumMethods
+	return app
+}
+
 // Handle serves a controller for the current mvc application's Router.
 // It accept any custom struct which its functions will be transformed
 // to routes.
@@ -218,7 +232,7 @@ func (app *Application) GetNamespaces() websocket.Namespaces {
 
 func (app *Application) handle(controller interface{}) *ControllerActivator {
 	// initialize the controller's activator, nothing too magical so far.
-	c := newControllerActivator(app.Router, controller, app.Dependencies, app.ErrorHandler)
+	c := newControllerActivator(app.Router, controller, app.Dependencies, app.Sorter, app.ErrorHandler)
 
 	// check the controller's "BeforeActivation" or/and "AfterActivation" method(s) between the `activate`
 	// call, which is simply parses the controller's methods, end-dev can register custom controller's methods