From 764a74e2ecd66ce8a34f8321dc40ebffabc58e0d Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@gmail.com>
Date: Sun, 17 Jan 2016 23:12:38 +0200
Subject: [PATCH] Added ServeFile and ServeFileUncompressed to be on par with
 net/http

---
 README.md  |  2 +-
 fs.go      | 63 +++++++++++++++++++++++++++++++++++++++++++++++++-----
 fs_test.go | 58 +++++++++++++++++++++++++++++++++++++++++++++++++
 server.go  |  2 ++
 4 files changed, 119 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index 652ce8a..94ade03 100644
--- a/README.md
+++ b/README.md
@@ -308,7 +308,7 @@ fastttp.ListenAndServe(":80", m)
   * http.Error() -> [ctx.Error()](https://godoc.org/github.com/valyala/fasthttp#RequestCtx.Error)
   * http.FileServer() -> [fasthttp.FSHandler()](https://godoc.org/github.com/valyala/fasthttp#FSHandler),
   [fasthttp.FS](https://godoc.org/github.com/valyala/fasthttp#FS)
-  * http.ServeFile() -> [ctx.SendFile()](https://godoc.org/github.com/valyala/fasthttp#RequestCtx.SendFile)
+  * http.ServeFile() -> [ctx.ServeFile()](https://godoc.org/github.com/valyala/fasthttp#ServeFile)
   * http.Redirect() -> [ctx.Redirect()](https://godoc.org/github.com/valyala/fasthttp#RequestCtx.Redirect)
   * http.NotFound() -> [ctx.NotFound()](https://godoc.org/github.com/valyala/fasthttp#RequestCtx.NotFound)
   * http.StripPrefix() -> [fasthttp.PathRewriteFunc](https://godoc.org/github.com/valyala/fasthttp#PathRewriteFunc)
diff --git a/fs.go b/fs.go
index d491966..bf58ec8 100644
--- a/fs.go
+++ b/fs.go
@@ -18,6 +18,59 @@ import (
 	"time"
 )
 
+// ServeFileUncompressed returns HTTP response containing file contents
+// from the given path.
+//
+// Directory contents is returned if path points to directory.
+//
+// ServeFile may be used for saving network traffic when serving files
+// with good compression ratio.
+//
+// See also RequestCtx.SendFile.
+func ServeFileUncompressed(ctx *RequestCtx, path string) {
+	ctx.Request.Header.DelBytes(strAcceptEncoding)
+	ServeFile(ctx, path)
+}
+
+// ServeFile returns HTTP response containing compressed file contents
+// from the given path.
+//
+// HTTP response may contain uncompressed file contents in the following cases:
+//
+//   * Missing 'Accept-Encoding: gzip' request header.
+//   * No write access to directory containing the file.
+//
+// Directory contents is returned if path points to directory.
+//
+// Use ServeFileUncompressed is you don't need serving compressed file contents.
+//
+// See also RequestCtx.SendFile.
+func ServeFile(ctx *RequestCtx, path string) {
+	rootFSOnce.Do(func() {
+		rootFSHandler = rootFS.NewRequestHandler()
+	})
+	if len(path) == 0 || path[0] != '/' {
+		// extend relative path to absolute path
+		var err error
+		if path, err = filepath.Abs(path); err != nil {
+			ctx.Logger().Printf("cannot resolve path %q to absolute file path: %s", path, err)
+		}
+	}
+	ctx.Request.SetRequestURI(path)
+	rootFSHandler(ctx)
+}
+
+var (
+	rootFSOnce sync.Once
+	rootFS     = &FS{
+		Root:               "/",
+		GenerateIndexPages: true,
+		Compress:           true,
+		AcceptByteRange:    true,
+	}
+	rootFSHandler RequestHandler
+)
+
 // PathRewriteFunc must return new request path based on arbitrary ctx
 // info such as ctx.Path().
 //
@@ -178,16 +231,16 @@ func (fs *FS) NewRequestHandler() RequestHandler {
 
 	root := fs.Root
 
-	// strip trailing slashes from the root path
-	for len(root) > 0 && root[len(root)-1] == '/' {
-		root = root[:len(root)-1]
-	}
-
 	// serve files from the current working directory if root is empty
 	if len(root) == 0 {
 		root = "."
 	}
 
+	// strip trailing slashes from the root path
+	for len(root) > 0 && root[len(root)-1] == '/' {
+		root = root[:len(root)-1]
+	}
+
 	cacheDuration := fs.CacheDuration
 	if cacheDuration <= 0 {
 		cacheDuration = FSHandlerCacheDuration
diff --git a/fs_test.go b/fs_test.go
index ea666ca..f2020e7 100644
--- a/fs_test.go
+++ b/fs_test.go
@@ -12,6 +12,64 @@ import (
 	"time"
 )
 
+func TestFSServeFileCompressed(t *testing.T) {
+	var ctx RequestCtx
+	var req Request
+	req.SetRequestURI("http://foobar.com/baz")
+	req.Header.Set("Accept-Encoding", "gzip")
+	ctx.Init(&req, nil, nil)
+
+	ServeFile(&ctx, "fs.go")
+
+	var resp Response
+	s := ctx.Response.String()
+	br := bufio.NewReader(bytes.NewBufferString(s))
+	if err := resp.Read(br); err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+
+	if string(resp.Header.Peek("Content-Encoding")) != "gzip" {
+		t.Fatalf("Unexpected 'Content-Encoding' %q. Expecting %q", resp.Header.Peek("Content-Encoding"), "gzip")
+	}
+
+	body, err := resp.BodyGunzip()
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	expectedBody, err := getFileContents("/fs.go")
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	if !bytes.Equal(body, expectedBody) {
+		t.Fatalf("unexpected body %q. expecting %q", body, expectedBody)
+	}
+}
+
+func TestFSServeFileUncompressed(t *testing.T) {
+	var ctx RequestCtx
+	var req Request
+	req.SetRequestURI("http://foobar.com/baz")
+	ctx.Init(&req, nil, nil)
+
+	ServeFileUncompressed(&ctx, "fs.go")
+
+	var resp Response
+	s := ctx.Response.String()
+	br := bufio.NewReader(bytes.NewBufferString(s))
+	if err := resp.Read(br); err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+
+	body := resp.Body()
+	expectedBody, err := getFileContents("/fs.go")
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	if !bytes.Equal(body, expectedBody) {
+		t.Fatalf("unexpected body %q. expecting %q", body, expectedBody)
+	}
+}
+
 func TestFSByteRangeConcurrent(t *testing.T) {
 	fs := &FS{
 		Root:            ".",
diff --git a/server.go b/server.go
index 268514b..9f8c44e 100644
--- a/server.go
+++ b/server.go
@@ -810,6 +810,8 @@ func (ctx *RequestCtx) ResetBody() {
 // Note that SendFile doesn't set Content-Type for the response body,
 // so set it yourself with SetContentType() before returning
 // from RequestHandler.
+//
+// See also ServeFile, FSHandler and FS.
 func (ctx *RequestCtx) SendFile(path string) error {
 	ifModStr := ctx.Request.Header.peek(strIfModifiedSince)
 	if len(ifModStr) > 0 {