mvc.Register and App.RegisterDependency

[xieyj-apple]

what diference between mvc.Register and App.RegisterDependency

App = iris.New()
App.RegisterDependency(xx)

_party := App .Party("/test")
mvc := mvc.New(_party)
mvc.Register(xxx)

[xieyj-apple]

controllerA -> serviceB -> serviceC

when i use
App.RegisterDependency(new(serviceB))
App.RegisterDependency(new(serviceC))

result :B.C is empty

[kataras]

The only difference is that app.RegisterDependency registers one or more dependencies to all of the mvc.New apps coming after that, so you don't need to call mvc.Register on each of your controller group. I don't understand the B.C is empty thing, please post a re-producable go code snippet for these cases so we can give you a more specific answer to your question. Thanks @xieyj-apple

[xieyj-apple]

type A struct {
	b B
}

type B struct {
	c C
}

type C struct {
	Name string
}

func newC() *C {
	return &C{Name: "4234"}
}

type TestController struct {
	a A
}

func (h *TestController) Get(ctx iris.Context) {
	fmt.Println("h say hello...", h.a.b.c.Name)
}

func main() {
	IrisApp := iris.New()
	IrisApp.RegisterDependency(newC)
	IrisApp.RegisterDependency(new(B))
	IrisApp.RegisterDependency(new(A))

	_party := IrisApp.Party("test")
	irisMvc := mvc.New(_party)
	irisMvc.Handle(new(TestController))
	if err := IrisApp.Listen("0.0.0.0:9988"); err != nil {
		_ = IrisApp.Shutdown(context.Background())
	}
}

when i visit http://localhost:9988/test it print : "h say hello..." not "h say hello...4234" why?

[kataras]

@xieyj-apple Because TestController.a is un-exported/private field and reflect has no access over it, so it can't set the newC->new(A) to the TestController.a dependency.

[xieyj-apple]

like this? it not work

type A struct {
	B B
}

type B struct {
	C C
}

type C struct {
	Name string
}

func newC() *C {
	return &C{Name: "4234"}
}

type TestController struct {
	A A
}

func (h *TestController) Get(ctx iris.Context) {
	fmt.Println("h say hello...", h.A.B.C.Name)
}

func main() {
	IrisApp := iris.New()
	IrisApp.RegisterDependency(newC)
	IrisApp.RegisterDependency(new(B))
	IrisApp.RegisterDependency(new(A))

	_party := IrisApp.Party("test")
	irisMvc := mvc.New(_party)
	irisMvc.Handle(new(TestController))
	if err := IrisApp.Listen("0.0.0.0:9988"); err != nil {
		_ = IrisApp.Shutdown(context.Background())
	}
}

[kataras]

Fixed @xieyj-apple :)

[xieyj-apple]

had new tag or version to fixed it?

[kataras]

Hello @xieyj-apple, I wasn't sure about the stability of this change that's why I didn't publish a new release, until today. Many apps would be broken if we change the default behavior like that. That's why I've added the app.ConfigureContainer().EnableStructDependents() and mvc.Application.EnableStructDependents() methods, you have to call this first in order for struct fields to be automatically binded based on previous dependencies that are structs. Here's a complete and working example:

package main

import (
	"fmt"

	"github.com/kataras/iris/v12"
	"github.com/kataras/iris/v12/mvc"
)

type A struct {
	B *B
}

type B struct {
	C *C
}

type C struct {
	Name string
}

func newC() *C {
	return &C{Name: "4234"}
}

type TestController struct {
	A *A
}

func (h *TestController) Get(ctx iris.Context) {
	fmt.Println("h say hello...", h.A.B.C.Name)
}

func main() {
	app := iris.New()
	app.Logger().SetLevel("debug")

	app.ConfigureContainer().EnableStructDependents()
	app.RegisterDependency(newC())
	app.RegisterDependency(new(B))
	app.RegisterDependency(new(A))

	testAPI := app.Party("/test")
	m := mvc.New(testAPI)
	// OR
	// m.EnableStructDependents()
	// m.Register(newC())
	// m.Register(new(B))
	// m.Register(new(A))
	m.Handle(new(TestController))
	app.Listen(":8080")
}

The latest release tag is v12.2.1