From 8c470e46a2227c52d3b26b2355ab6b6aa8b1cd1a Mon Sep 17 00:00:00 2001
From: "Gerasimos (Makis) Maropoulos" <kataras2006@hotmail.com>
Date: Wed, 6 May 2020 08:00:56 +0300
Subject: [PATCH] mvc controllers and methods: provide mvc.Application
 automatically

Former-commit-id: 991d8e72c3c231813a455dd0680cd8a83b82abb1
---
 HISTORY.md             |  1 +
 mvc/controller_test.go | 23 ++++++++++++++++++++++-
 mvc/mvc.go             | 39 +++++++++++++++++++++++++++++++++++++--
 3 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/HISTORY.md b/HISTORY.md
index 260a261e..e531574e 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -145,6 +145,7 @@ Prior to this version the `iris.Context` was the only one dependency that has be
 
 | Type | Maps To |
 |------|:---------|
+| [*mvc.Application](https://pkg.go.dev/github.com/kataras/iris/v12/mvc?tab=doc#Application) | Current MVC Application |
 | [iris.Context](https://pkg.go.dev/github.com/kataras/iris/v12/context?tab=doc#Context) | Current Iris Context |
 | [*sessions.Session](https://pkg.go.dev/github.com/kataras/iris/v12/sessions?tab=doc#Session) | Current Iris Session |
 | [context.Context](https://golang.org/pkg/context/#Context) | [ctx.Request().Context()](https://golang.org/pkg/net/http/#Request.Context) |
diff --git a/mvc/controller_test.go b/mvc/controller_test.go
index 1919b08c..3b695dbc 100644
--- a/mvc/controller_test.go
+++ b/mvc/controller_test.go
@@ -506,7 +506,7 @@ type testControllerNotCreateNewDueManuallySettingAllFields struct {
 }
 
 func (c *testControllerNotCreateNewDueManuallySettingAllFields) AfterActivation(a AfterActivation) {
-	if n := len(a.DependenciesReadOnly()) - len(hero.BuiltinDependencies); n != 1 {
+	if n := len(a.DependenciesReadOnly()) - len(hero.BuiltinDependencies) - 1; /* Application */ n != 1 {
 		c.T.Fatalf(`expecting 1 dependency;
 - the 'T' and the 'TitlePointer' are manually binded (nonzero fields on initilization)
 - controller has no more than these two fields, it's a singleton
@@ -624,3 +624,24 @@ func TestControllersInsideControllerDeep(t *testing.T) {
 	e := httptest.New(t, app)
 	e.GET("/something").Expect().Status(httptest.StatusOK).Body().Equal("foo bar")
 }
+
+type testApplicationDependency struct {
+	App *Application
+}
+
+func (c *testApplicationDependency) Get() string {
+	return c.App.Name
+}
+
+func TestApplicationDependency(t *testing.T) {
+	app := iris.New()
+	m := New(app).SetName("app1")
+	m.Handle(new(testApplicationDependency))
+
+	m2 := m.Clone(app.Party("/other")).SetName("app2")
+	m2.Handle(new(testApplicationDependency))
+
+	e := httptest.New(t, app)
+	e.GET("/").Expect().Status(httptest.StatusOK).Body().Equal("app1")
+	e.GET("/other").Expect().Status(httptest.StatusOK).Body().Equal("app2")
+}
diff --git a/mvc/mvc.go b/mvc/mvc.go
index 6edfb817..9c6944cc 100644
--- a/mvc/mvc.go
+++ b/mvc/mvc.go
@@ -25,6 +25,8 @@ import (
 // See `mvc#New` for more.
 type Application struct {
 	container *hero.Container
+	// This Application's Name. Keep names unique to each other.
+	Name string
 
 	Router               router.Party
 	Controllers          []*ControllerActivator
@@ -32,10 +34,34 @@ type Application struct {
 }
 
 func newApp(subRouter router.Party, container *hero.Container) *Application {
-	return &Application{
+	app := &Application{
 		Router:    subRouter,
 		container: container,
 	}
+
+	// Register this Application so any field or method's input argument of
+	// *mvc.Application can point to the current MVC application that the controller runs on.
+	registerBuiltinDependencies(container, app)
+	return app
+}
+
+// See `hero.BuiltinDependencies` too, here we are registering dependencies per MVC Application.
+func registerBuiltinDependencies(container *hero.Container, deps ...interface{}) {
+	for _, dep := range deps {
+		depTyp := reflect.TypeOf(dep)
+		for i, dependency := range container.Dependencies {
+			if dependency.Static {
+				if dependency.DestType == depTyp {
+					// Remove any existing before register this one (see app.Clone).
+					copy(container.Dependencies[i:], container.Dependencies[i+1:])
+					container.Dependencies = container.Dependencies[:len(container.Dependencies)-1]
+					break
+				}
+			}
+		}
+
+		container.Register(dep)
+	}
 }
 
 // New returns a new mvc Application based on a "party".
@@ -44,7 +70,7 @@ func newApp(subRouter router.Party, container *hero.Container) *Application {
 //
 // Example: `New(app.Party("/todo"))` or `New(app)` as it's the same as `New(app.Party("/"))`.
 func New(party router.Party) *Application {
-	return newApp(party, party.ConfigureContainer().Container)
+	return newApp(party, party.ConfigureContainer().Container.Clone())
 }
 
 // Configure creates a new controller and configures it,
@@ -78,6 +104,15 @@ func (app *Application) Configure(configurators ...func(*Application)) *Applicat
 	return app
 }
 
+// SetName sets a unique name to this MVC Application.
+// Used for logging, not used in runtime yet, but maybe useful for future features.
+//
+// It returns this Application.
+func (app *Application) SetName(appName string) *Application {
+	app.Name = appName
+	return app
+}
+
 // Register appends one or more values as dependencies.
 // The value can be a single struct value-instance or a function
 // which has one input and one output, the input should be