add a basic group mechanism

This adds a basic group mechanism to run a bunch of middlewares for the
same path.

lib/router.go

@@ -16,6 +16,8 @@ type Router struct {
   funcList []ContextFunc
   // the router to use as the main entity
   router *httprouter.Router
+  // the parent router, if any
+  parent *Router
 }
 
 // Bundle all parameters into the context to make it easier to push important
@@ -38,7 +40,14 @@ type Context struct {
 type ContextFunc func(*Context) error
 
 func NewRouter() *Router {
-  return &Router{"", make([]ContextFunc, 0), httprouter.New()}
+  return &Router{"", make([]ContextFunc, 0), httprouter.New(), nil}
+}
+
+func (r *Router) fullpath(path string) string {
+  if r.parent != nil {
+    return r.parent.fullpath(r.path + path)
+  }
+  return r.path + path
 }
 
 func (r *Router) Get(path string, target ContextFunc) {
@@ -57,14 +66,10 @@ func (r *Router) Delete(path string, target ContextFunc) {
   r.addRoute("DELETE", path, target)
 }
 
-func (r *Router) Use(middleware ContextFunc) {
-  r.funcList = addToFuncList(r.funcList, middleware)
-}
-
 func (router *Router) addRoute(method, path string, target ContextFunc) {
   router.router.Handle(
     method,
-    router.path + path,
+    router.fullpath(path),
     router.createHandleFunction(target),
   )
 }
@@ -84,6 +89,14 @@ func (r *Router) createHandleFunction(target ContextFunc) httprouter.Handle {
   }
 }
 
+func (r *Router) Use(middleware ContextFunc) {
+  r.funcList = addToFuncList(r.funcList, middleware)
+}
+
+func (r *Router) NewGroup(path string) *Router {
+  return &Router{path, make([]ContextFunc, 0), r.router, r}
+}
+
 func (r *Router) Start() {
   log.Print("Starting to listen for incoming requests ...")
   log.Fatal(http.ListenAndServe(":9292", r.router))

main.go

@@ -8,8 +8,14 @@ import (
 
 func main() {
   router := lib.NewRouter()
-  router.Use(func(c *lib.Context) error {
-    fmt.Fprint(c.Response, "Hello says the middleware!")
+  authentication := router.NewGroup("/admin")
+  authentication.Use(func(c *lib.Context) error {
+    c.Response.Header().Add("Content-Type", "text/html")
+    fmt.Fprint(c.Response, "Hello says the middleware!<br />")
+    return nil
+  })
+  authentication.Get("/", func(c *lib.Context) error {
+    fmt.Fprint(c.Response, "Admin panel, yay!")
     return nil
   })
   controller.DefineRoutes(router)