Return http.HandlerFunc instead of http.Handler

static/static.go

@@ -6,17 +6,23 @@ import (
 )
 
 // Dir serves the files in the given directory or
-// uses the given handler to handles missing files
+// uses the given HandlerFunc to handles missing files
-func Dir(dirPath string, stripPrefix string, notFoundHandler http.Handler) http.Handler {
+func Dir(dirPath string, stripPrefix string, notFound http.HandlerFunc) http.HandlerFunc {
+
 	root := http.Dir(dirPath)
 	fs := http.FileServer(root)
+
 	fn := func(w http.ResponseWriter, r *http.Request) {
 		if _, err := os.Stat(dirPath + r.RequestURI); os.IsNotExist(err) {
-			notFoundHandler.ServeHTTP(w, r)
+			notFound.ServeHTTP(w, r)
 		} else {
 			fs.ServeHTTP(w, r)
 		}
 	}
+
 	handler := http.StripPrefix(stripPrefix, http.HandlerFunc(fn))
-	return handler
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		handler.ServeHTTP(w, r)
+	})
 }

static/static_test.go

@@ -0,0 +1,33 @@
+package static
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestStaticDir(t *testing.T) {
+
+	req, err := http.NewRequest("GET", "/test.txt", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	notFound := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		t.Error("notFound should not be invoked")
+	})
+
+	rr := httptest.NewRecorder()
+	handler := Dir("./testdata", "/", notFound)
+
+	handler.ServeHTTP(rr, req)
+
+	if g, e := rr.Code, http.StatusOK; g != e {
+		t.Errorf("rr.Code: got '%v', expected '%v'", g, e)
+	}
+
+	if g, e := rr.Body.String(), "Hello World"; g != e {
+		t.Errorf("rr.Body.String(): got '%v', expected '%v'", g, e)
+	}
+
+}

static/testdata/test.txt

@@ -0,0 +1 @@
+Hello World