new feature: versioned controllers

Former-commit-id: c797e23c78b1e74bbe9ba56673f3a98f17f5e2f7

mvc/versioning.go

@@ -0,0 +1,38 @@
+package mvc
+
+import (
+	"github.com/kataras/iris/v12/context"
+	"github.com/kataras/iris/v12/core/router"
+	"github.com/kataras/iris/v12/versioning"
+)
+
+// Version returns a valid `Option` that can be passed to the `Application.Handle` method.
+// It requires a specific "version" constraint for a Controller,
+// e.g. ">1, <=2" or just "1".
+//
+//
+// Usage:
+// 	m := mvc.New(dataRouter)
+// 	m.Handle(new(v1Controller), mvc.Version("1"))
+// 	m.Handle(new(v2Controller), mvc.Version("2.3"))
+// 	m.Handle(new(v3Controller), mvc.Version(">=3, <4"))
+// 	m.Handle(new(noVersionController))
+//
+// See the `versioning` package's documentation for more information on
+// how the version is extracted from incoming requests.
+//
+// Note that this Option will set the route register rule to `RouteOverlap`.
+func Version(version string) OptionFunc {
+	return func(c *ControllerActivator) {
+		c.Router().SetRegisterRule(router.RouteOverlap) // required for this feature.
+
+		c.Use(func(ctx context.Context) {
+			if !versioning.Match(ctx, version) {
+				ctx.StopExecution()
+				return
+			}
+
+			ctx.Next()
+		})
+	}
+}