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

Former-commit-id: ed635ee95de7160cde11eaabc0c1dcb0e460a620

_examples/auth/basicauth/main.go

@@ -0,0 +1,57 @@
+package main
+
+import (
+	"time"
+
+	"github.com/kataras/iris/v12"
+	"github.com/kataras/iris/v12/middleware/basicauth"
+)
+
+func newApp() *iris.Application {
+	app := iris.New()
+
+	authConfig := basicauth.Config{
+		Users:   map[string]string{"myusername": "mypassword", "mySecondusername": "mySecondpassword"},
+		Realm:   "Authorization Required", // defaults to "Authorization Required"
+		Expires: time.Duration(30) * time.Minute,
+	}
+
+	authentication := basicauth.New(authConfig)
+
+	// to global app.Use(authentication) (or app.UseGlobal before the .Run)
+	// to routes
+	/*
+		app.Get("/mysecret", authentication, h)
+	*/
+
+	app.Get("/", func(ctx iris.Context) { ctx.Redirect("/admin") })
+
+	// to party
+
+	needAuth := app.Party("/admin", authentication)
+	{
+		//http://localhost:8080/admin
+		needAuth.Get("/", h)
+		// http://localhost:8080/admin/profile
+		needAuth.Get("/profile", h)
+
+		// http://localhost:8080/admin/settings
+		needAuth.Get("/settings", h)
+	}
+
+	return app
+}
+
+func main() {
+	app := newApp()
+	// open http://localhost:8080/admin
+	app.Listen(":8080")
+}
+
+func h(ctx iris.Context) {
+	username, password, _ := ctx.Request().BasicAuth()
+	// third parameter it will be always true because the middleware
+	// makes sure for that, otherwise this handler will not be executed.
+
+	ctx.Writef("%s %s:%s", ctx.Path(), username, password)
+}