MM-26065: Reverts Brotli encoding. (#14834)

* MM-26065: Reverts Brotli encoding.

* MM-26065: Removes package reference.

web/handlers.go

@@ -14,7 +14,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/mkraft/gziphandler"
+	"github.com/NYTimes/gziphandler"
 	"github.com/opentracing/opentracing-go"
 	"github.com/opentracing/opentracing-go/ext"
 	spanlog "github.com/opentracing/opentracing-go/log"

web/static.go

@@ -9,23 +9,15 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/NYTimes/gziphandler"
 	"github.com/mattermost/mattermost-server/v5/mlog"
 	"github.com/mattermost/mattermost-server/v5/model"
 	"github.com/mattermost/mattermost-server/v5/utils"
 	"github.com/mattermost/mattermost-server/v5/utils/fileutils"
-	"github.com/mkraft/gziphandler"
 )
 
 var robotsTxt = []byte("User-agent: *\nDisallow: /\n")
 
-// the static content types that are Brotli encoded rather than gzipped.
-var brotliEncodedContent = map[string]string{
-	"js":  "application/javascript",
-	"css": "text/css",
-}
-
-var brotliContentTypes []string
-
 func (w *Web) InitStatic() {
 	if *w.ConfigService.Config().ServiceSettings.WebserverMode != "disabled" {
 		if err := utils.UpdateAssetsSubpathFromConfig(w.ConfigService.Config()); err != nil {
@@ -37,20 +29,11 @@ func (w *Web) InitStatic() {
 
 		subpath, _ := utils.GetSubpathFromConfig(w.ConfigService.Config())
 
-		staticHandler := brotliFilesHandler(staticFilesHandler(http.StripPrefix(path.Join(subpath, "static"), http.FileServer(http.Dir(staticDir)))))
+		staticHandler := staticFilesHandler(http.StripPrefix(path.Join(subpath, "static"), http.FileServer(http.Dir(staticDir))))
 		pluginHandler := staticFilesHandler(http.StripPrefix(path.Join(subpath, "static", "plugins"), http.FileServer(http.Dir(*w.ConfigService.Config().PluginSettings.ClientDirectory))))
 
 		if *w.ConfigService.Config().ServiceSettings.WebserverMode == "gzip" {
-			for _, ct := range brotliEncodedContent {
-				brotliContentTypes = append(brotliContentTypes, ct)
-			}
-
-			everythingExceptBrotliGzipHandler, err := gziphandler.GzipHandlerWithOpts(gziphandler.ContentTypeExceptions(brotliContentTypes))
-			if err != nil {
-				mlog.Error("Failed to initialize gziphandler", mlog.Err(err))
-			}
-
-			staticHandler = everythingExceptBrotliGzipHandler(staticHandler)
+			staticHandler = gziphandler.GzipHandler(staticHandler)
 			pluginHandler = gziphandler.GzipHandler(pluginHandler)
 		}
 
@@ -88,26 +71,6 @@ func root(c *Context, w http.ResponseWriter, r *http.Request) {
 	http.ServeFile(w, r, filepath.Join(staticDir, "root.html"))
 }
 
-func acceptsEncodingBrotli(r *http.Request) bool {
-	directives := strings.Fields(r.Header.Get("Accept-Encoding"))
-	for _, directive := range directives {
-		if strings.ToLower(directive) == "br" {
-			return true
-		}
-	}
-	return false
-}
-
-func requestingBrotliFileExtension(r *http.Request) (bool, string) {
-	extension := r.URL.Path[strings.LastIndex(r.URL.Path, ".")+1:]
-	for bx, ct := range brotliEncodedContent {
-		if bx == extension {
-			return true, ct
-		}
-	}
-	return false, ""
-}
-
 func staticFilesHandler(handler http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		//wrap our ResponseWriter with our no-cache 404-handler
@@ -124,21 +87,6 @@ func staticFilesHandler(handler http.Handler) http.Handler {
 	})
 }
 
-func brotliFilesHandler(handler http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if model.BuildNumber != "dev" {
-			isRequestingBrotliFile, contentType := requestingBrotliFileExtension(r)
-			if isRequestingBrotliFile && acceptsEncodingBrotli(r) {
-				r.URL.Path = r.URL.Path + ".br"
-				w.Header().Set("Content-Encoding", "br")
-				w.Header().Set("Content-Type", contentType)
-			}
-		}
-
-		handler.ServeHTTP(w, r)
-	})
-}
-
 type notFoundNoCacheResponseWriter struct {
 	http.ResponseWriter
 }

web/static_test.go

@@ -1,58 +0,0 @@
-// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
-// See LICENSE.txt for license information.
-
-package web
-
-import (
-	"fmt"
-	"net/http"
-	"net/http/httptest"
-	"strings"
-	"testing"
-
-	"github.com/stretchr/testify/require"
-)
-
-var tests = []struct {
-	requestURL            string
-	requestContentType    string
-	requestAcceptEncoding []string
-	expectBrotli          bool
-}{
-	{"http://test.com/foo.js", "application/javascript", []string{"br"}, true},
-	{"http://test.com/foo.css", "text/css", []string{"br"}, true},
-	{"http://test.com/foo.jss", "text/plain; charset=utf-8", []string{"gzip"}, false},
-	{"http://test.com/foo.css", "text/plain; charset=utf-8", []string{"gzip"}, false},
-	{"http://test.com/foo.jsx", "text/plain; charset=utf-8", []string{"br"}, false},
-	{"http://test.com/foo.xcss", "text/plain; charset=utf-8", []string{"gzip"}, false},
-}
-
-type mockHandler struct{}
-
-func (mh mockHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	fmt.Fprintf(w, "hello")
-}
-
-func TestBrotliFilesHandler(t *testing.T) {
-	for _, tt := range tests {
-		t.Run(fmt.Sprintf("%v", tt), func(t *testing.T) {
-
-			req := httptest.NewRequest("GET", tt.requestURL, nil)
-			req.Header.Set("Accept-Encoding", strings.Join(tt.requestAcceptEncoding, ", "))
-			w := httptest.NewRecorder()
-
-			handler := brotliFilesHandler(mockHandler{})
-			handler.ServeHTTP(w, req)
-
-			resp := w.Result()
-
-			require.Equal(t, tt.expectBrotli, resp.Header.Get("Content-Encoding") == "br")
-			if tt.expectBrotli {
-				require.Equal(t, tt.requestURL+".br", req.URL.String())
-			} else {
-				require.Equal(t, tt.requestURL, req.URL.String())
-			}
-			require.Equal(t, tt.requestContentType, resp.Header.Get("Content-Type"))
-		})
-	}
-}