add two new examples and share the app's specific logger instance with sessions databases and APIBuilder

_examples/routing/subdomains/www/main.go

@@ -1,8 +1,6 @@
 package main
 
-import (
-	"github.com/kataras/iris/v12"
-)
+import "github.com/kataras/iris/v12"
 
 func newApp() *iris.Application {
 	app := iris.New()
@@ -44,9 +42,9 @@ func newApp() *iris.Application {
 			ctx.Writef("hi from www.mydomain.com")
 		})
 	}
-	// See also the "subdomains/redirect" to register redirect router wrappers between subdomains,
+	// See "subdomains/redirect" to register redirect router wrappers between subdomains,
 	// i.e mydomain.com to www.mydomain.com (like facebook does for SEO reasons(;)).
-
+	// And ./www-method example.
 	return app
 }
 
@@ -64,9 +62,7 @@ func main() {
 	// http://www.mydomain.com/contact
 	// http://www.mydomain.com/api/users
 	// http://www.mydomain.com/api/users/42
-	if err := app.Listen("mydomain.com:80"); err != nil {
-		panic(err)
-	}
+	app.Listen("mydomain.com:80")
 }
 
 func info(ctx iris.Context) {

_examples/routing/subdomains/www/www-method/main.go

@@ -0,0 +1,51 @@
+package main
+
+import "github.com/kataras/iris/v12"
+
+func newApp() *iris.Application {
+	app := iris.New()
+	// This will create a new "www" subdomain
+	// and redirect root-level domain requests
+	// to that one:
+	www := app.WWW()
+	www.Get("/", info)
+	www.Get("/about", info)
+	www.Get("/contact", info)
+
+	www.PartyFunc("/api/users", func(r iris.Party) {
+		r.Get("/", info)
+		r.Get("/{id:uint64}", info)
+
+		r.Post("/", info)
+
+		r.Put("/{id:uint64}", info)
+	})
+
+	return app
+}
+
+func main() {
+	app := newApp()
+	// http://mydomain.com
+	// http://mydomain.com/about
+	// http://imydomain.com/contact
+	// http://mydomain.com/api/users
+	// http://mydomain.com/api/users/42
+
+	// http://www.mydomain.com
+	// http://www.mydomain.com/hi
+	// http://www.mydomain.com/about
+	// http://www.mydomain.com/contact
+	// http://www.mydomain.com/api/users
+	// http://www.mydomain.com/api/users/42
+	app.Listen("mydomain.com:80")
+}
+
+func info(ctx iris.Context) {
+	method := ctx.Method()
+	subdomain := ctx.Subdomain()
+	path := ctx.Path()
+
+	ctx.Writef("\nInfo\n\n")
+	ctx.Writef("Method: %s\nSubdomain: %s\nPath: %s", method, subdomain, path)
+}