Improve middleware functionality

- Allow specifying if middlewares are for paths with ID, without ID,
  or both
- Add GetRequestedResourceAndDoMiddleware to make it easier to create
  middlewares that access resource by ID

babyapi.go

@@ -20,9 +20,10 @@ type API[T Resource] struct {
 	name string
 	base string
 
-	subAPIs     map[string]RelatedAPI
-	middlewares chi.Middlewares
-	storage     Storage[T]
+	subAPIs       map[string]RelatedAPI
+	middlewares   []func(http.Handler) http.Handler
+	idMiddlewares []func(http.Handler) http.Handler
+	storage       Storage[T]
 
 	server *http.Server
 	quit   chan os.Signal
@@ -58,6 +59,7 @@ func NewAPI[T Resource](name, base string, instance func() T) *API[T] {
 		base,
 		map[string]RelatedAPI{},
 		nil,
+		nil,
 		MapStorage[T]{},
 		nil,
 		make(chan os.Signal, 1),
@@ -177,9 +179,20 @@ func (a *API[T]) Storage() Storage[T] {
 	return a.storage
 }
 
-// AddMiddlewares appends chi.Middlewares to existing middlewares
-func (a *API[T]) AddMiddlewares(m chi.Middlewares) *API[T] {
-	a.middlewares = append(a.middlewares, m...)
+// AddPersistentMiddleware adds a middleware which is active on paths with and without resource ID
+func (a *API[T]) AddPersistentMiddleware(m func(http.Handler) http.Handler) *API[T] {
+	return a.AddMiddleware(m).AddIDMiddleware(m)
+}
+
+// AddMiddleware adds a middleware which is active only on the paths without resource ID
+func (a *API[T]) AddMiddleware(m func(http.Handler) http.Handler) *API[T] {
+	a.middlewares = append(a.middlewares, m)
+	return a
+}
+
+// AddIDMiddleware adds a middleware which is active only on the paths including a resource ID
+func (a *API[T]) AddIDMiddleware(m func(http.Handler) http.Handler) *API[T] {
+	a.idMiddlewares = append(a.idMiddlewares, m)
 	return a
 }
 

babyapi_test.go

@@ -732,13 +732,11 @@ func TestAPIModifiers(t *testing.T) {
 
 	api := babyapi.NewAPI[*Album]("Albums", "/albums", func() *Album { return &Album{} }).
 		SetCustomResponseCode(http.MethodPut, http.StatusTeapot).
-		AddMiddlewares(chi.Middlewares{
-			func(next http.Handler) http.Handler {
-				return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-					middleware++
-					next.ServeHTTP(w, r)
-				})
-			},
+		AddMiddleware(func(next http.Handler) http.Handler {
+			return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				middleware++
+				next.ServeHTTP(w, r)
+			})
 		}).
 		SetOnCreateOrUpdate(func(r *http.Request, a *Album) *babyapi.ErrResponse {
 			onCreateOrUpdate++

helpers.go

@@ -64,6 +64,29 @@ func (a *API[T]) GetRequestedResourceAndDo(do func(*http.Request, T) (render.Ren
 	}
 }
 
+func (a *API[T]) GetRequestedResourceAndDoMiddleware(do func(*http.Request, T) *ErrResponse) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			logger := GetLoggerFromContext(r.Context())
+
+			resource, httpErr := a.GetRequestedResource(r)
+			if httpErr != nil {
+				logger.Error("error getting requested resource", "error", httpErr.Error())
+				_ = render.Render(w, r, httpErr)
+				return
+			}
+
+			httpErr = do(r, resource)
+			if httpErr != nil {
+				_ = render.Render(w, r, httpErr)
+				return
+			}
+
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
 // ReadRequestBodyAndDo is a wrapper that handles decoding the request body into the resource type and rendering a response
 func (a *API[T]) ReadRequestBodyAndDo(do func(*http.Request, T) (T, *ErrResponse)) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {

router.go

@@ -48,6 +48,10 @@ func (a *API[T]) Route(r chi.Router) {
 		r.Get("/", a.GetAll)
 
 		r.With(a.resourceExistsMiddleware).Route(fmt.Sprintf("/{%s}", a.IDParamKey()), func(r chi.Router) {
+			for _, middleware := range a.idMiddlewares {
+				r.Use(middleware)
+			}
+
 			r.Get("/", a.Get)
 			r.Delete("/", a.Delete)
 			r.With(a.requestBodyMiddleware).Put("/", a.Put)