feat: add support to serve fs.FS

group.go

@@ -1,6 +1,10 @@
 package router
 
-import "github.com/valyala/fasthttp"
+import (
+	"io/fs"
+
+	"github.com/valyala/fasthttp"
+)
 
 // Group returns a new group.
 // Path auto-correction, including trailing slashes, is enabled by default.
@@ -86,7 +90,7 @@ func (g *Group) ANY(path string, handler fasthttp.RequestHandler) {
 	g.router.ANY(g.prefix+path, handler)
 }
 
-// ServeFiles serves files from the given file system root.
+// ServeFiles serves files from the given file system root path.
 // The path must end with "/{filepath:*}", files are then served from the local
 // path /defined/root/dir/{filepath:*}.
 // For example if root is "/etc" and {filepath:*} is "passwd", the local file
@@ -101,6 +105,21 @@ func (g *Group) ServeFiles(path string, rootPath string) {
 	g.router.ServeFiles(g.prefix+path, rootPath)
 }
 
+// ServeFS serves files from the given file system.
+// The path must end with "/{filepath:*}", files are then served from the local
+// path /defined/root/dir/{filepath:*}.
+// For example if root is "/etc" and {filepath:*} is "passwd", the local file
+// "/etc/passwd" would be served.
+// Internally a fasthttp.FSHandler is used, therefore http.NotFound is used instead
+// Use:
+//
+//	router.ServeFS("/src/{filepath:*}", myFilesystem)
+func (g *Group) ServeFS(path string, filesystem fs.FS) {
+	validatePath(path)
+
+	g.router.ServeFS(g.prefix+path, filesystem)
+}
+
 // ServeFilesCustom serves files from the given file system settings.
 // The path must end with "/{filepath:*}", files are then served from the local
 // path /defined/root/dir/{filepath:*}.

group_test.go

@@ -94,6 +94,7 @@ func TestGroup(t *testing.T) {
 		ctx.SetStatusCode(fasthttp.StatusOK)
 	})
 	r6.ServeFiles("/static/{filepath:*}", "./")
+	r6.ServeFS("/static/fs/{filepath:*}", fsTestFilesystem)
 	r6.ServeFilesCustom("/custom/static/{filepath:*}", &fasthttp.FS{Root: "./"})
 
 	uris := []string{
@@ -110,6 +111,8 @@ func TestGroup(t *testing.T) {
 		"POST /moo/foo/foo/bar HTTP/1.1\r\n\r\n",
 		// testing multiple sub-router group - r6 (grouped from r5) to serve files
 		"GET /moo/foo/foo/static/router.go HTTP/1.1\r\n\r\n",
+		// testing multiple sub-router group - r6 (grouped from r5) to serve fs
+		"GET /moo/foo/foo/static/fs/LICENSE HTTP/1.1\r\n\r\n",
 		// testing multiple sub-router group - r6 (grouped from r5) to serve files with custom settings
 		"GET /moo/foo/foo/custom/static/router.go HTTP/1.1\r\n\r\n",
 	}

router.go

@@ -2,6 +2,7 @@ package router
 
 import (
 	"fmt"
+	"io/fs"
 	"strings"
 
 	"github.com/fasthttp/router/radix"
@@ -15,8 +16,7 @@ import (
 const MethodWild = "*"
 
 var (
-	defaultContentType = []byte("text/plain; charset=utf-8")
-	questionMark       = byte('?')
+	questionMark = byte('?')
 
 	// MatchedRoutePathParam is the param name under which the path of the matched
 	// route is stored, if Router.SaveMatchedRoutePath is set.
@@ -164,7 +164,7 @@ func (r *Router) ANY(path string, handler fasthttp.RequestHandler) {
 	r.Handle(MethodWild, path, handler)
 }
 
-// ServeFiles serves files from the given file system root.
+// ServeFiles serves files from the given file system root path.
 // The path must end with "/{filepath:*}", files are then served from the local
 // path /defined/root/dir/{filepath:*}.
 // For example if root is "/etc" and {filepath:*} is "passwd", the local file
@@ -182,6 +182,27 @@ func (r *Router) ServeFiles(path string, rootPath string) {
 	})
 }
 
+// ServeFS serves files from the given file system.
+// The path must end with "/{filepath:*}", files are then served from the local
+// path /defined/root/dir/{filepath:*}.
+// For example if root is "/etc" and {filepath:*} is "passwd", the local file
+// "/etc/passwd" would be served.
+// Internally a fasthttp.FSHandler is used, therefore fasthttp.NotFound is used instead
+// Use:
+//
+//	router.ServeFS("/src/{filepath:*}", myFilesystem)
+func (r *Router) ServeFS(path string, filesystem fs.FS) {
+	r.ServeFilesCustom(path, &fasthttp.FS{
+		FS:                 filesystem,
+		Root:               "",
+		AllowEmptyRoot:     true,
+		GenerateIndexPages: true,
+		AcceptByteRange:    true,
+		Compress:           true,
+		CompressBrotli:     true,
+	})
+}
+
 // ServeFilesCustom serves files from the given file system settings.
 // The path must end with "/{filepath:*}", files are then served from the local
 // path /defined/root/dir/{filepath:*}.
@@ -193,7 +214,7 @@ func (r *Router) ServeFiles(path string, rootPath string) {
 //
 //	router.ServeFilesCustom("/src/{filepath:*}", *customFS)
 func (r *Router) ServeFilesCustom(path string, fs *fasthttp.FS) {
-	suffix := "/{filepath:*}"
+	const suffix = "/{filepath:*}"
 
 	if !strings.HasSuffix(path, suffix) {
 		panic("path must end with " + suffix + " in path '" + path + "'")

router_test.go

@@ -3,6 +3,7 @@ package router
 import (
 	"bufio"
 	"bytes"
+	"embed"
 	"fmt"
 	"io/ioutil"
 	"math/rand"
@@ -37,6 +38,9 @@ var httpMethods = []string{
 	"CUSTOM",
 }
 
+//go:embed LICENSE
+var fsTestFilesystem embed.FS
+
 func randomHTTPMethod() string {
 	method := httpMethods[rand.Intn(len(httpMethods)-1)]
 
@@ -934,8 +938,11 @@ func TestRouterServeFiles(t *testing.T) {
 	if recv == nil {
 		t.Fatal("registering path not ending with '{filepath:*}' did not panic")
 	}
+
 	body := []byte("fake ico")
-	ioutil.WriteFile(os.TempDir()+"/favicon.ico", body, 0644)
+	if err := os.WriteFile(os.TempDir()+"/favicon.ico", body, 0644); err != nil {
+		t.Fatal(err)
+	}
 
 	r.ServeFiles("/{filepath:*}", os.TempDir())
 
@@ -954,6 +961,38 @@ func TestRouterServeFiles(t *testing.T) {
 	})
 }
 
+func TestRouterServeFS(t *testing.T) {
+	r := New()
+
+	recv := catchPanic(func() {
+		r.ServeFS("/noFilepath", fsTestFilesystem)
+	})
+	if recv == nil {
+		t.Fatal("registering path not ending with '{filepath:*}' did not panic")
+	}
+
+	body, err := os.ReadFile("LICENSE")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	r.ServeFS("/{filepath:*}", fsTestFilesystem)
+
+	assertWithTestServer(t, "GET /LICENSE HTTP/1.1\r\n\r\n", r.Handler, func(rw *readWriter) {
+		br := bufio.NewReader(&rw.w)
+		var resp fasthttp.Response
+		if err := resp.Read(br); err != nil {
+			t.Fatalf("Unexpected error when reading response: %s", err)
+		}
+		if resp.Header.StatusCode() != 200 {
+			t.Fatalf("Unexpected status code %d. Expected %d", resp.Header.StatusCode(), 200)
+		}
+		if !bytes.Equal(resp.Body(), body) {
+			t.Fatalf("Unexpected body %q. Expected %q", resp.Body(), string(body))
+		}
+	})
+}
+
 func TestRouterServeFilesCustom(t *testing.T) {
 	r := New()