From aa59f0c26e3cf95b4570979965c6fcfd4e5ff0ab Mon Sep 17 00:00:00 2001
From: vicanso <vicansocanbico@gmail.com>
Date: Mon, 24 Dec 2018 16:42:55 +0800
Subject: [PATCH] refactor: gzip only support for text/javascript/json

---
 middleware/static_serve.go      | 23 ++++++++++++++++++++++-
 middleware/static_serve_test.go | 19 +++++++++++++++++++
 2 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/middleware/static_serve.go b/middleware/static_serve.go
index 674a718..c4aca63 100644
--- a/middleware/static_serve.go
+++ b/middleware/static_serve.go
@@ -54,6 +54,12 @@ var (
 	errNotAllowQueryString = getStaticServeError("static serve not allow query string", http.StatusBadRequest)
 	errNotFound            = getStaticServeError("static file not found", http.StatusNotFound)
 	errOutOfPath           = getStaticServeError("out of path", http.StatusBadRequest)
+
+	defaultCompressTypes = []string{
+		"text",
+		"javascript",
+		"json",
+	}
 )
 
 func (fs *FS) outOfPath(file string) bool {
@@ -131,6 +137,19 @@ func doGzip(buf []byte, level int) ([]byte, error) {
 	return b.Bytes(), nil
 }
 
+func isCompressable(contentType string) bool {
+	compressable := false
+	for _, v := range defaultCompressTypes {
+		if compressable {
+			break
+		}
+		if strings.Contains(contentType, v) {
+			compressable = true
+		}
+	}
+	return compressable
+}
+
 // NewStaticServe create a static servce middleware
 func NewStaticServe(staticFile StaticFile, config StaticServeConfig) cod.Handler {
 	if config.Path == "" {
@@ -197,7 +216,9 @@ func NewStaticServe(staticFile StaticFile, config StaticServeConfig) cod.Handler
 				c.SetHeader(cod.HeaderLastModified, lmd)
 			}
 		}
-		if config.Gzip && len(buf) >= config.CompressMinLength {
+		if config.Gzip &&
+			len(buf) >= config.CompressMinLength &&
+			isCompressable(contentType) {
 			gzipBuf, e := doGzip(buf, 0)
 			// 如果压缩成功，则使用压缩数据
 			// 失败则忽略
diff --git a/middleware/static_serve_test.go b/middleware/static_serve_test.go
index 33cc276..811213a 100644
--- a/middleware/static_serve_test.go
+++ b/middleware/static_serve_test.go
@@ -146,6 +146,25 @@ func TestStaticServe(t *testing.T) {
 		}
 	})
 
+	t.Run("not compresss", func(t *testing.T) {
+		fn := NewStaticServe(staticFile, StaticServeConfig{
+			Path:              staticPath,
+			Mount:             "/static",
+			Gzip:              true,
+			CompressMinLength: 1,
+		})
+		req := httptest.NewRequest("GET", "/static/banner.jpg", nil)
+		res := httptest.NewRecorder()
+		c := cod.NewContext(res, req)
+		c.Next = func() error {
+			return nil
+		}
+		err := fn(c)
+		if err != nil || c.Headers.Get(cod.HeaderContentEncoding) == "gzip" {
+			t.Fatalf("serve image fail, %v", err)
+		}
+	})
+
 	t.Run("get index.html", func(t *testing.T) {
 		fn := NewStaticServe(staticFile, StaticServeConfig{
 			Path:              staticPath,