🐛 bug: fix mounting doesn't work if when to declare it before routes

app.go

@@ -116,6 +116,8 @@ type App struct {
 	latestGroup *Group
 	// TLS handler
 	tlsHandler *TLSHandler
+	// check added routes of sub-apps
+	subAppsRoutesAdded bool
 }
 
 // Config is a struct holding the server settings.
@@ -584,27 +586,17 @@ func (app *App) SetTLSHandler(tlsHandler *TLSHandler) {
 // any of the fiber's sub apps are added to the application's error handlers
 // to be invoked on errors that happen within the prefix route.
 func (app *App) Mount(prefix string, fiber *App) Router {
-	stack := fiber.Stack()
 	prefix = strings.TrimRight(prefix, "/")
 	if prefix == "" {
 		prefix = "/"
 	}
 
-	for m := range stack {
-		for r := range stack[m] {
-			route := app.copyRoute(stack[m][r])
-			app.addRoute(route.Method, app.addPrefixToRoute(prefix, route))
-		}
-	}
-
 	// Support for configs of mounted-apps and sub-mounted-apps
 	for mountedPrefixes, subApp := range fiber.appList {
 		app.appList[prefix+mountedPrefixes] = subApp
 		subApp.init()
 	}
 
-	atomic.AddUint32(&app.handlersCount, fiber.handlersCount)
-
 	return app
 }
 
@@ -975,6 +967,7 @@ func (app *App) ErrorHandler(ctx *Ctx, err error) error {
 	)
 
 	for prefix, subApp := range app.appList {
+		fmt.Println(prefix)
 		if prefix != "" && strings.HasPrefix(ctx.path, prefix) {
 			parts := len(strings.Split(prefix, "/"))
 			if mountedPrefixParts <= parts {
@@ -1024,7 +1017,66 @@ func (app *App) startupProcess() *App {
 	}
 
 	app.mutex.Lock()
+	defer app.mutex.Unlock()
+
+	// add routes of sub-apps
+	if !app.subAppsRoutesAdded {
+		app.appendSubAppLists(app.appList)
+		app.addSubAppsRoutes(app.appList)
+
+		app.subAppsRoutesAdded = true
+	}
+
+	// build route tree stack
 	app.buildTree()
-	app.mutex.Unlock()
+
 	return app
 }
+
+// appendSubAppLists supports nested for sub apps
+func (app *App) appendSubAppLists(appList map[string]*App, parent ...string) {
+	for prefix, subApp := range appList {
+		// skip real app
+		if prefix == "" {
+			continue
+		}
+
+		if len(parent) > 0 {
+			prefix = parent[0] + prefix
+		}
+
+		if _, ok := app.appList[prefix]; !ok {
+			app.appList[prefix] = subApp
+		}
+
+		if len(subApp.appList) > 1 {
+			app.appendSubAppLists(subApp.appList, prefix)
+		}
+
+	}
+}
+
+// addSubAppsRoutes adds routes of sub apps nestedly when to start the server
+func (app *App) addSubAppsRoutes(appList map[string]*App, parent ...string) {
+	for prefix, subApp := range appList {
+		// skip real app
+		if prefix == "" {
+			continue
+		}
+
+		if len(parent) > 0 {
+			prefix = parent[0] + prefix
+		}
+
+		// add routes
+		stack := subApp.stack
+		for m := range stack {
+			for r := range stack[m] {
+				route := app.copyRoute(stack[m][r])
+				app.addRoute(route.Method, app.addPrefixToRoute(prefix, route))
+			}
+		}
+
+		atomic.AddUint32(&app.handlersCount, subApp.handlersCount)
+	}
+}

app_test.go

@@ -323,6 +323,44 @@ func Test_App_Mount(t *testing.T) {
 	utils.AssertEqual(t, uint32(2), app.handlersCount)
 }
 
+// go test -run Test_App_Mount_Nested
+func Test_App_Mount_Nested(t *testing.T) {
+	app := New()
+	one := New()
+	two := New()
+	three := New()
+
+	two.Mount("/three", three)
+	app.Mount("/one", one)
+	one.Mount("/two", two)
+
+	one.Get("/doe", func(c *Ctx) error {
+		return c.SendStatus(StatusOK)
+	})
+
+	two.Get("/nested", func(c *Ctx) error {
+		return c.SendStatus(StatusOK)
+	})
+
+	three.Get("/test", func(c *Ctx) error {
+		return c.SendStatus(StatusOK)
+	})
+
+	resp, err := app.Test(httptest.NewRequest(MethodGet, "/one/doe", nil))
+	utils.AssertEqual(t, nil, err, "app.Test(req)")
+	utils.AssertEqual(t, 200, resp.StatusCode, "Status code")
+
+	resp, err = app.Test(httptest.NewRequest(MethodGet, "/one/two/nested", nil))
+	utils.AssertEqual(t, nil, err, "app.Test(req)")
+	utils.AssertEqual(t, 200, resp.StatusCode, "Status code")
+
+	resp, err = app.Test(httptest.NewRequest(MethodGet, "/one/two/three/test", nil))
+	utils.AssertEqual(t, nil, err, "app.Test(req)")
+	utils.AssertEqual(t, 200, resp.StatusCode, "Status code")
+
+	utils.AssertEqual(t, uint32(6), app.handlersCount)
+}
+
 func Test_App_Use_Params(t *testing.T) {
 	app := New()
 

group.go

@@ -8,7 +8,6 @@ import (
 	"fmt"
 	"reflect"
 	"strings"
-	"sync/atomic"
 )
 
 // Group struct
@@ -23,28 +22,18 @@ type Group struct {
 // It's very useful to split up a large API as many independent routers and
 // compose them as a single service using Mount.
 func (grp *Group) Mount(prefix string, fiber *App) Router {
-	stack := fiber.Stack()
 	groupPath := getGroupPath(grp.Prefix, prefix)
 	groupPath = strings.TrimRight(groupPath, "/")
 	if groupPath == "" {
 		groupPath = "/"
 	}
 
-	for m := range stack {
-		for r := range stack[m] {
-			route := grp.app.copyRoute(stack[m][r])
-			grp.app.addRoute(route.Method, grp.app.addPrefixToRoute(groupPath, route))
-		}
-	}
-
 	// Support for configs of mounted-apps and sub-mounted-apps
 	for mountedPrefixes, subApp := range fiber.appList {
 		grp.app.appList[groupPath+mountedPrefixes] = subApp
 		subApp.init()
 	}
 
-	atomic.AddUint32(&grp.app.handlersCount, fiber.handlersCount)
-
 	return grp
 }
 

router.go

@@ -436,19 +436,20 @@ func (app *App) addRoute(method string, route *Route) {
 		app.routesRefreshed = true
 	}
 
-	app.mutex.Lock()
+	//app.mutex.Lock()
 	app.latestRoute = route
 	if err := app.hooks.executeOnRouteHooks(*route); err != nil {
 		panic(err)
 	}
-	app.mutex.Unlock()
+	//app.mutex.Unlock()
 }
 
 // buildTree build the prefix tree from the previously registered routes
 func (app *App) buildTree() *App {
 	if !app.routesRefreshed {
 		return app
 	}
+
 	// loop all the methods and stacks and create the prefix tree
 	for m := range intMethod {
 		tsMap := make(map[string][]*Route)
@@ -462,6 +463,7 @@ func (app *App) buildTree() *App {
 		}
 		app.treeStack[m] = tsMap
 	}
+
 	// loop the methods and tree stacks and add global stack and sort everything
 	for m := range intMethod {
 		tsMap := app.treeStack[m]