Replace go-bindata with Go embed

Co-authored-by: nrwiersma <nick@wiersma.co.za>

pkg/api/dashboard.go

@@ -1,59 +0,0 @@
-package api
-
-import (
-	"net/http"
-	"net/url"
-
-	assetfs "github.com/elazarl/go-bindata-assetfs"
-	"github.com/gorilla/mux"
-	"github.com/traefik/traefik/v2/pkg/log"
-)
-
-// DashboardHandler expose dashboard routes.
-type DashboardHandler struct {
-	Assets *assetfs.AssetFS
-}
-
-// Append add dashboard routes on a router.
-func (g DashboardHandler) Append(router *mux.Router) {
-	if g.Assets == nil {
-		log.WithoutContext().Error("No assets for dashboard")
-		return
-	}
-
-	// Expose dashboard
-	router.Methods(http.MethodGet).
-		Path("/").
-		HandlerFunc(func(resp http.ResponseWriter, req *http.Request) {
-			http.Redirect(resp, req, safePrefix(req)+"/dashboard/", http.StatusFound)
-		})
-
-	router.Methods(http.MethodGet).
-		PathPrefix("/dashboard/").
-		Handler(http.StripPrefix("/dashboard/", http.FileServer(g.Assets)))
-}
-
-func (g DashboardHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	// allow iframes from our domains only
-	// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/frame-src
-	w.Header().Set("Content-Security-Policy", "frame-src 'self' https://traefik.io https://*.traefik.io;")
-	http.FileServer(g.Assets).ServeHTTP(w, r)
-}
-
-func safePrefix(req *http.Request) string {
-	prefix := req.Header.Get("X-Forwarded-Prefix")
-	if prefix == "" {
-		return ""
-	}
-
-	parse, err := url.Parse(prefix)
-	if err != nil {
-		return ""
-	}
-
-	if parse.Host != "" {
-		return ""
-	}
-
-	return parse.Path
-}

pkg/api/dashboard/dashboard.go

@@ -0,0 +1,68 @@
+package dashboard
+
+import (
+	"io/fs"
+	"net/http"
+	"net/url"
+
+	"github.com/gorilla/mux"
+	"github.com/traefik/traefik/v2/webui"
+)
+
+// Handler expose dashboard routes.
+type Handler struct {
+	assets fs.FS // optional assets, to override the webui.FS default
+}
+
+// Append adds dashboard routes on the given router, optionally using the given
+// assets (or webui.FS otherwise).
+func Append(router *mux.Router, customAssets fs.FS) {
+	assets := customAssets
+	if assets == nil {
+		assets = webui.FS
+	}
+	// Expose dashboard
+	router.Methods(http.MethodGet).
+		Path("/").
+		HandlerFunc(func(resp http.ResponseWriter, req *http.Request) {
+			http.Redirect(resp, req, safePrefix(req)+"/dashboard/", http.StatusFound)
+		})
+
+	router.Methods(http.MethodGet).
+		PathPrefix("/dashboard/").
+		HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			// allow iframes from our domains only
+			// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/frame-src
+			w.Header().Set("Content-Security-Policy", "frame-src 'self' https://traefik.io https://*.traefik.io;")
+			http.StripPrefix("/dashboard/", http.FileServer(http.FS(assets))).ServeHTTP(w, r)
+		})
+}
+
+func (g Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	assets := g.assets
+	if assets == nil {
+		assets = webui.FS
+	}
+	// allow iframes from our domains only
+	// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/frame-src
+	w.Header().Set("Content-Security-Policy", "frame-src 'self' https://traefik.io https://*.traefik.io;")
+	http.FileServer(http.FS(assets)).ServeHTTP(w, r)
+}
+
+func safePrefix(req *http.Request) string {
+	prefix := req.Header.Get("X-Forwarded-Prefix")
+	if prefix == "" {
+		return ""
+	}
+
+	parse, err := url.Parse(prefix)
+	if err != nil {
+		return ""
+	}
+
+	if parse.Host != "" {
+		return ""
+	}
+
+	return parse.Path
+}

pkg/api/dashboard/dashboard_test.go

@@ -1,12 +1,14 @@
-package api
+package dashboard
 
 import (
-	"fmt"
+	"errors"
+	"io/fs"
 	"net/http"
 	"net/http/httptest"
 	"testing"
+	"testing/fstest"
+	"time"
 
-	assetfs "github.com/elazarl/go-bindata-assetfs"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -59,48 +61,30 @@ func Test_safePrefix(t *testing.T) {
 func Test_ContentSecurityPolicy(t *testing.T) {
 	testCases := []struct {
 		desc     string
-		handler  DashboardHandler
+		handler  Handler
 		expected int
 	}{
 		{
 			desc: "OK",
-			handler: DashboardHandler{
-				Assets: &assetfs.AssetFS{
-					Asset: func(path string) ([]byte, error) {
-						return []byte{}, nil
-					},
-					AssetDir: func(path string) ([]string, error) {
-						return []string{}, nil
-					},
-				},
+			handler: Handler{
+				assets: fstest.MapFS{"foobar.html": &fstest.MapFile{
+					Mode:    0755,
+					ModTime: time.Now(),
+				}},
 			},
 			expected: http.StatusOK,
 		},
 		{
 			desc: "Not found",
-			handler: DashboardHandler{
-				Assets: &assetfs.AssetFS{
-					Asset: func(path string) ([]byte, error) {
-						return []byte{}, fmt.Errorf("not found")
-					},
-					AssetDir: func(path string) ([]string, error) {
-						return []string{}, fmt.Errorf("not found")
-					},
-				},
+			handler: Handler{
+				assets: fstest.MapFS{},
 			},
 			expected: http.StatusNotFound,
 		},
 		{
 			desc: "Internal server error",
-			handler: DashboardHandler{
-				Assets: &assetfs.AssetFS{
-					Asset: func(path string) ([]byte, error) {
-						return []byte{}, fmt.Errorf("oops")
-					},
-					AssetDir: func(path string) ([]string, error) {
-						return []string{}, fmt.Errorf("oops")
-					},
-				},
+			handler: Handler{
+				assets: errorFS{},
 			},
 			expected: http.StatusInternalServerError,
 		},
@@ -122,3 +106,9 @@ func Test_ContentSecurityPolicy(t *testing.T) {
 		})
 	}
 }
+
+type errorFS struct{}
+
+func (e errorFS) Open(name string) (fs.File, error) {
+	return nil, errors.New("oops")
+}

pkg/api/handler.go

@@ -6,7 +6,6 @@ import (
 	"reflect"
 	"strings"
 
-	assetfs "github.com/elazarl/go-bindata-assetfs"
 	"github.com/gorilla/mux"
 	"github.com/traefik/traefik/v2/pkg/config/dynamic"
 	"github.com/traefik/traefik/v2/pkg/config/runtime"
@@ -48,10 +47,7 @@ type RunTimeRepresentation struct {
 
 // Handler serves the configuration and status of Traefik on API endpoints.
 type Handler struct {
-	dashboard       bool
-	debug           bool
-	staticConfig    static.Configuration
-	dashboardAssets *assetfs.AssetFS
+	staticConfig static.Configuration
 
 	// runtimeConfiguration is the data set used to create all the data representations exposed by the API.
 	runtimeConfiguration *runtime.Configuration
@@ -73,11 +69,8 @@ func New(staticConfig static.Configuration, runtimeConfig *runtime.Configuration
 	}
 
 	return &Handler{
-		dashboard:            staticConfig.API.Dashboard,
-		dashboardAssets:      staticConfig.API.DashboardAssets,
 		runtimeConfiguration: rConfig,
 		staticConfig:         staticConfig,
-		debug:                staticConfig.API.Debug,
 	}
 }
 
@@ -85,7 +78,7 @@ func New(staticConfig static.Configuration, runtimeConfig *runtime.Configuration
 func (h Handler) createRouter() *mux.Router {
 	router := mux.NewRouter()
 
-	if h.debug {
+	if h.staticConfig.API.Debug {
 		DebugHandler{}.Append(router)
 	}
 
@@ -118,10 +111,6 @@ func (h Handler) createRouter() *mux.Router {
 
 	version.Handler{}.Append(router)
 
-	if h.dashboard {
-		DashboardHandler{Assets: h.dashboardAssets}.Append(router)
-	}
-
 	return router
 }