reorganization of _examples and add some new examples such as iris+groupcache+mysql+docker

Former-commit-id: ed635ee95de7160cde11eaabc0c1dcb0e460a620

_examples/mvc/vuejs-todo-mvc/src/web/controllers/todo_controller.go

@@ -0,0 +1,66 @@
+package controllers
+
+import (
+	"github.com/kataras/iris/v12/_examples/mvc/vuejs-todo-mvc/src/todo"
+
+	"github.com/kataras/iris/v12"
+	"github.com/kataras/iris/v12/mvc"
+	"github.com/kataras/iris/v12/sessions"
+	"github.com/kataras/iris/v12/websocket"
+)
+
+// TodoController is our TODO app's web controller.
+type TodoController struct {
+	Service todo.Service
+
+	Session *sessions.Session
+
+	NS *websocket.NSConn
+}
+
+// BeforeActivation called once before the server ran, and before
+// the routes and dependencies binded.
+// You can bind custom things to the controller, add new methods, add middleware,
+// add dependencies to the struct or the method(s) and more.
+func (c *TodoController) BeforeActivation(b mvc.BeforeActivation) {
+	// this could be binded to a controller's function input argument
+	// if any, or struct field if any:
+	b.Dependencies().Register(func(ctx iris.Context) (items []todo.Item) {
+		ctx.ReadJSON(&items)
+		return
+	}) // Note: from Iris v12.2 these type of dependencies are automatically resolved.
+}
+
+// Get handles the GET: /todos route.
+func (c *TodoController) Get() []todo.Item {
+	return c.Service.Get(c.Session.ID())
+}
+
+// PostItemResponse the response data that will be returned as json
+// after a post save action of all todo items.
+type PostItemResponse struct {
+	Success bool `json:"success"`
+}
+
+var emptyResponse = PostItemResponse{Success: false}
+
+// Post handles the POST: /todos route.
+func (c *TodoController) Post(newItems []todo.Item) PostItemResponse {
+	if err := c.Service.Save(c.Session.ID(), newItems); err != nil {
+		return emptyResponse
+	}
+
+	return PostItemResponse{Success: true}
+}
+
+func (c *TodoController) Save(msg websocket.Message) error {
+	id := c.Session.ID()
+	c.NS.Conn.Server().Broadcast(nil, websocket.Message{
+		Namespace: msg.Namespace,
+		Event:     "saved",
+		To:        id,
+		Body:      websocket.Marshal(c.Service.Get(id)),
+	})
+
+	return nil
+}