New: context#NextOr && context#NextOrNotFound and some performance improvements on the awesome https://github.com/kataras/iris/pull/909 pushed a while ago

Former-commit-id: 35dd2ab80b69a5bea6f35f58e636bc11229d9921

core/router/api_builder.go

@@ -90,7 +90,7 @@ type APIBuilder struct {
 	doneHandlers context.Handlers
 	// global done handlers, order doesn't matter
 	doneGlobalHandlers context.Handlers
-	// fallback stack, LIFO order
+	// fallback stack, LIFO order, initialized on first `Fallback`.
 	fallbackStack *FallbackStack
 	// the per-party
 	relativePath string
@@ -437,13 +437,13 @@ func (api *APIBuilder) DoneGlobal(handlers ...context.Handler) {
 // Fallback appends Handler(s) to the current fallback stack.
 // Handler(s) is(are) called from Fallback stack when no route found and before sending NotFound status.
 // Therefore Handler(s) in Fallback stack could send another thing than NotFound status,
-//   if `Context.Next()` method is not called.
+//   if `context.NextOrNotFound()` method is not called.
 // Done & DoneGlobal Handlers are not called.
 func (api *APIBuilder) Fallback(middleware ...context.Handler) {
 	api.fallbackStack.Add(middleware)
 }
 
-// FallBackStack returns Fallback stack, this is implementation of interface RoutesProvider
+// GetFallBackStack returns Fallback stack, this is implementation of interface RoutesProvider
 //   that is used in Router building by the RequestHandler.
 func (api *APIBuilder) GetFallBackStack() *FallbackStack {
 	return api.fallbackStack

core/router/fallback_stack.go

@@ -1,16 +1,12 @@
 package router
 
-import (
-	"net/http"
-
-	"github.com/kataras/iris/context"
-)
+import "github.com/kataras/iris/context"
 
 // FallbackStack is a stack (with LIFO calling order) for fallback handlers
 // A fallback handler(s) is(are) called from Fallback stack
 //   when no route found and before sending NotFound status.
 // Therefore Handler(s) in Fallback stack could send another thing than NotFound status,
-//   if `Context.Next()` method is not called.
+//   if `context#NextOrNotFound()` method is not called.
 // Done & DoneGlobal Handlers are not called.
 type FallbackStack struct {
 	parent   *FallbackStack
@@ -65,14 +61,5 @@ func (stk *FallbackStack) List() context.Handlers {
 	return res
 }
 
-// NewFallbackStack create a new Fallback stack with as first entry
-//   a handler which send NotFound status (the default)
-func NewFallbackStack() *FallbackStack {
-	return &FallbackStack{
-		handlers: context.Handlers{
-			func(ctx context.Context) {
-				ctx.StatusCode(http.StatusNotFound)
-			},
-		},
-	}
-}
+// NewFallbackStack create a new empty Fallback stack.
+func NewFallbackStack() *FallbackStack { return &FallbackStack{} }

core/router/fallback_stack_test.go

@@ -94,8 +94,7 @@ func TestFallbackStackCall(t *testing.T) {
 	// setup fallback handler
 	app.Fallback(func(ctx context.Context) {
 		if ctx.Method() != "GET" {
-			ctx.Next()
-
+			ctx.NextOrNotFound() //	it checks if we have next, otherwise fire 404 not found.
 			return
 		}
 

core/router/handler.go

@@ -38,6 +38,11 @@ type routerHandler struct {
 	trees         []*tree
 	hosts         bool // true if at least one route contains a Subdomain.
 	fallbackStack *FallbackStack
+	// on build: true if fallbackStack.Size() > 0,
+	// reduces the checks because fallbackStack is NEVER nil (api_builder.go always initializes it).
+	// If re-checked needed (serve-time fallback handler added)
+	// then a re-build/refresh of the application's router is necessary, as with every handler.
+	hasFallbackHandlers bool
 }
 
 var _ RequestHandler = &routerHandler{}
@@ -93,6 +98,7 @@ func (h *routerHandler) Build(provider RoutesProvider) error {
 	registeredRoutes := provider.GetRoutes()
 	h.trees = h.trees[0:0] // reset, inneed when rebuilding.
 	h.fallbackStack = provider.GetFallBackStack()
+	h.hasFallbackHandlers = h.fallbackStack.Size() > 0
 
 	// sort, subdomains goes first.
 	sort.Slice(registeredRoutes, func(i, j int) bool {
@@ -248,11 +254,12 @@ func (h *routerHandler) HandleRequest(ctx context.Context) {
 		}
 	}
 
-	if h.fallbackStack == nil {
-		ctx.StatusCode(http.StatusNotFound)
-	} else {
+	if h.hasFallbackHandlers {
 		ctx.Do(h.fallbackStack.List())
+		return
 	}
+
+	ctx.StatusCode(http.StatusNotFound)
 }
 
 // RouteExists checks if a route exists