FEMT: Add feature toggle and expose the service in regular grafana (#104428)

packages/grafana-data/src/types/featureToggles.gen.ts

@@ -1014,6 +1014,10 @@ export interface FeatureToggles {
   */
   pluginsAutoUpdate?: boolean;
   /**
+  * Register MT frontend
+  */
+  multiTenantFrontend?: boolean;
+  /**
   * Enables the alerting list view v2 preview toggle
   */
   alertingListViewV2PreviewToggle?: boolean;

pkg/api/api.go

@@ -48,6 +48,7 @@ import (
 	"github.com/grafana/grafana/pkg/services/dashboards"
 	"github.com/grafana/grafana/pkg/services/datasources"
 	"github.com/grafana/grafana/pkg/services/featuremgmt"
+	"github.com/grafana/grafana/pkg/services/frontend"
 	"github.com/grafana/grafana/pkg/services/org"
 	"github.com/grafana/grafana/pkg/services/pluginsintegration/pluginaccesscontrol"
 	publicdashboardsapi "github.com/grafana/grafana/pkg/services/publicdashboards/api"
@@ -85,6 +86,14 @@ func (hs *HTTPServer) registerRoutes() {
 	r.Get("/login", hs.LoginView)
 	r.Get("/invite/:code", hs.Index)
 
+	if hs.Features.IsEnabledGlobally(featuremgmt.FlagMultiTenantFrontend) {
+		index, err := frontend.NewIndexProvider(hs.Cfg, hs.License)
+		if err != nil {
+			panic(err) // ???
+		}
+		r.Get("/mtfe", index.HandleRequest)
+	}
+
 	// authed views
 	r.Get("/", reqSignedIn, hs.Index)
 	r.Get("/profile/", reqSignedInNoAnonymous, hs.Index)

pkg/middleware/csp.go

@@ -31,7 +31,7 @@ func ContentSecurityPolicy(cfg *setting.Cfg, logger log.Logger) func(http.Handle
 func nonceMiddleware(next http.Handler, logger log.Logger) http.Handler {
 	return http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
 		ctx := contexthandler.FromContext(req.Context())
-		nonce, err := generateNonce()
+		nonce, err := GenerateNonce()
 		if err != nil {
 			logger.Error("Failed to generate CSP nonce", "err", err)
 			ctx.JsonApiErr(500, "Failed to generate CSP nonce", err)
@@ -68,7 +68,7 @@ func ReplacePolicyVariables(policyTemplate, appURL, nonce string) string {
 	return policy
 }
 
-func generateNonce() (string, error) {
+func GenerateNonce() (string, error) {
 	var buf [16]byte
 	if _, err := io.ReadFull(rand.Reader, buf[:]); err != nil {
 		return "", err

pkg/server/module_server.go

@@ -9,6 +9,8 @@ import (
 	"strconv"
 	"sync"
 
+	"github.com/prometheus/client_golang/prometheus"
+
 	"github.com/grafana/dskit/services"
 	"github.com/grafana/grafana/pkg/api"
 	"github.com/grafana/grafana/pkg/infra/log"
@@ -16,16 +18,24 @@ import (
 	"github.com/grafana/grafana/pkg/services/authz"
 	"github.com/grafana/grafana/pkg/services/featuremgmt"
 	"github.com/grafana/grafana/pkg/services/frontend"
+	"github.com/grafana/grafana/pkg/services/licensing"
 	"github.com/grafana/grafana/pkg/setting"
 	"github.com/grafana/grafana/pkg/storage/unified/resource"
 	"github.com/grafana/grafana/pkg/storage/unified/sql"
-	"github.com/prometheus/client_golang/prometheus"
 )
 
 // NewModule returns an instance of a ModuleServer, responsible for managing
 // dskit modules (services).
-func NewModule(opts Options, apiOpts api.ServerOptions, features featuremgmt.FeatureToggles, cfg *setting.Cfg, storageMetrics *resource.StorageMetrics, indexMetrics *resource.BleveIndexMetrics, promGatherer prometheus.Gatherer) (*ModuleServer, error) {
+func NewModule(opts Options,
-	s, err := newModuleServer(opts, apiOpts, features, cfg, storageMetrics, indexMetrics, promGatherer)
+	apiOpts api.ServerOptions,
+	features featuremgmt.FeatureToggles,
+	cfg *setting.Cfg,
+	storageMetrics *resource.StorageMetrics,
+	indexMetrics *resource.BleveIndexMetrics,
+	promGatherer prometheus.Gatherer,
+	license licensing.Licensing,
+) (*ModuleServer, error) {
+	s, err := newModuleServer(opts, apiOpts, features, cfg, storageMetrics, indexMetrics, promGatherer, license)
 	if err != nil {
 		return nil, err
 	}
@@ -37,7 +47,7 @@ func NewModule(opts Options, apiOpts api.ServerOptions, features featuremgmt.Fea
 	return s, nil
 }
 
-func newModuleServer(opts Options, apiOpts api.ServerOptions, features featuremgmt.FeatureToggles, cfg *setting.Cfg, storageMetrics *resource.StorageMetrics, indexMetrics *resource.BleveIndexMetrics, promGatherer prometheus.Gatherer) (*ModuleServer, error) {
+func newModuleServer(opts Options, apiOpts api.ServerOptions, features featuremgmt.FeatureToggles, cfg *setting.Cfg, storageMetrics *resource.StorageMetrics, indexMetrics *resource.BleveIndexMetrics, promGatherer prometheus.Gatherer, license licensing.Licensing) (*ModuleServer, error) {
 	rootCtx, shutdownFn := context.WithCancel(context.Background())
 
 	s := &ModuleServer{
@@ -56,6 +66,7 @@ func newModuleServer(opts Options, apiOpts api.ServerOptions, features featuremg
 		storageMetrics:   storageMetrics,
 		indexMetrics:     indexMetrics,
 		promGatherer:     promGatherer,
+		license:          license,
 	}
 
 	return s, nil
@@ -79,6 +90,7 @@ type ModuleServer struct {
 	mtx              sync.Mutex
 	storageMetrics   *resource.StorageMetrics
 	indexMetrics     *resource.BleveIndexMetrics
+	license          licensing.Licensing
 
 	pidFile     string
 	version     string
@@ -153,7 +165,7 @@ func (s *ModuleServer) Run() error {
 	})
 
 	m.RegisterModule(modules.FrontendServer, func() (services.Service, error) {
-		return frontend.ProvideFrontendService(s.cfg, s.promGatherer)
+		return frontend.ProvideFrontendService(s.cfg, s.promGatherer, s.license)
 	})
 
 	m.RegisterModule(modules.All, nil)

pkg/services/featuremgmt/registry.go

@@ -1738,13 +1738,19 @@ var (
 			FrontendOnly: true,
 		},
 		{
-
 			Name:         "pluginsAutoUpdate",
 			Description:  "Enables auto-updating of users installed plugins",
 			Stage:        FeatureStageExperimental,
 			FrontendOnly: false,
 			Owner:        grafanaPluginsPlatformSquad,
 		},
+		{
+			Name:         "multiTenantFrontend",
+			Description:  "Register MT frontend",
+			Stage:        FeatureStageExperimental,
+			FrontendOnly: false,
+			Owner:        grafanaFrontendPlatformSquad,
+		},
 		{
 			Name:         "alertingListViewV2PreviewToggle",
 			Description:  "Enables the alerting list view v2 preview toggle",

pkg/services/featuremgmt/toggles_gen.csv

@@ -228,6 +228,7 @@ unifiedNavbars,GA,@grafana/plugins-platform-backend,false,false,true
 logsPanelControls,preview,@grafana/observability-logs,false,false,true
 metricsFromProfiles,experimental,@grafana/observability-traces-and-profiling,false,false,true
 pluginsAutoUpdate,experimental,@grafana/plugins-platform-backend,false,false,false
+multiTenantFrontend,experimental,@grafana/grafana-frontend-platform,false,false,false
 alertingListViewV2PreviewToggle,privatePreview,@grafana/alerting-squad,false,false,true
 alertRuleUseFiredAtForStartsAt,experimental,@grafana/alerting-squad,false,false,false
 alertingBulkActionsInUI,GA,@grafana/alerting-squad,false,false,true

pkg/services/featuremgmt/toggles_gen.go

@@ -923,6 +923,10 @@ const (
 	// Enables auto-updating of users installed plugins
 	FlagPluginsAutoUpdate = "pluginsAutoUpdate"
 
+	// FlagMultiTenantFrontend
+	// Register MT frontend
+	FlagMultiTenantFrontend = "multiTenantFrontend"
+
 	// FlagAlertingListViewV2PreviewToggle
 	// Enables the alerting list view v2 preview toggle
 	FlagAlertingListViewV2PreviewToggle = "alertingListViewV2PreviewToggle"

pkg/services/featuremgmt/toggles_gen.json

@@ -1976,6 +1976,18 @@
         "codeowner": "@grafana/alerting-squad"
       }
     },
+    {
+      "metadata": {
+        "name": "multiTenantFrontend",
+        "resourceVersion": "1745438197175",
+        "creationTimestamp": "2025-04-23T19:56:37Z"
+      },
+      "spec": {
+        "description": "Register MT frontend",
+        "stage": "experimental",
+        "codeowner": "@grafana/grafana-frontend-platform"
+      }
+    },
     {
       "metadata": {
         "name": "multiTenantTempCredentials",
@@ -1989,6 +2001,19 @@
         "hideFromDocs": true
       }
     },
+    {
+      "metadata": {
+        "name": "multitenantFrontend",
+        "resourceVersion": "1745438122785",
+        "creationTimestamp": "2025-04-23T19:55:22Z",
+        "deletionTimestamp": "2025-04-23T19:56:37Z"
+      },
+      "spec": {
+        "description": "Register MT frontend",
+        "stage": "experimental",
+        "codeowner": "@grafana/grafana-frontend-platform"
+      }
+    },
     {
       "metadata": {
         "name": "mysqlAnsiQuotes",

pkg/services/frontend/frontend_service.go

@@ -6,11 +6,13 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/grafana/dskit/services"
-	"github.com/grafana/grafana/pkg/infra/log"
-	"github.com/grafana/grafana/pkg/setting"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
+
+	"github.com/grafana/dskit/services"
+	"github.com/grafana/grafana/pkg/infra/log"
+	"github.com/grafana/grafana/pkg/services/licensing"
+	"github.com/grafana/grafana/pkg/setting"
 )
 
 type frontendService struct {
@@ -20,13 +22,21 @@ type frontendService struct {
 	log          log.Logger
 	errChan      chan error
 	promGatherer prometheus.Gatherer
+
+	index *IndexProvider
 }
 
-func ProvideFrontendService(cfg *setting.Cfg, promGatherer prometheus.Gatherer) (*frontendService, error) {
+func ProvideFrontendService(cfg *setting.Cfg, promGatherer prometheus.Gatherer, license licensing.Licensing) (*frontendService, error) {
+	index, err := NewIndexProvider(cfg, license)
+	if err != nil {
+		return nil, err
+	}
+
 	s := &frontendService{
 		cfg:          cfg,
 		log:          log.New("frontend-server"),
 		promGatherer: promGatherer,
+		index:        index,
 	}
 	s.BasicService = services.NewBasicService(s.start, s.running, s.stop)
 	return s, nil
@@ -64,7 +74,7 @@ func (s *frontendService) newFrontendServer(ctx context.Context) *http.Server {
 
 	router := http.NewServeMux()
 	router.Handle("/metrics", promhttp.HandlerFor(s.promGatherer, promhttp.HandlerOpts{EnableOpenMetrics: true}))
-	router.HandleFunc("/", s.handleRequest)
+	router.HandleFunc("/", s.index.HandleRequest)
 
 	server := &http.Server{
 		// 5s timeout for header reads to avoid Slowloris attacks (https://thetooth.io/blog/slowloris-attack/)
@@ -76,34 +86,3 @@ func (s *frontendService) newFrontendServer(ctx context.Context) *http.Server {
 
 	return server
 }
-
-func (s *frontendService) handleRequest(writer http.ResponseWriter, request *http.Request) {
-	// This should:
-	// - get correct asset urls from fs or cdn
-	// - generate a nonce
-	// - render them into the index.html
-	// - and return it to the user!
-
-	s.log.Info("handling request", "method", request.Method, "url", request.URL.String())
-	htmlContent := `<!DOCTYPE html>
-<html>
-<head>
-    <title>Grafana Frontend Server</title>
-    <style>
-        body {
-            font-family: sans-serif;
-        }
-    </style>
-</head>
-<body>
-    <h1>Grafana Frontend Server</h1>
-    <p>This is a simple static HTML page served by the Grafana frontend server module.</p>
-</body>
-</html>`
-
-	writer.Header().Set("Content-Type", "text/html; charset=utf-8")
-	_, err := writer.Write([]byte(htmlContent))
-	if err != nil {
-		s.log.Error("could not write to response", "err", err)
-	}
-}

pkg/services/frontend/index.go

@@ -0,0 +1,108 @@
+package frontend
+
+import (
+	"context"
+	"embed"
+	"errors"
+	"fmt"
+	"html/template"
+	"net/http"
+	"syscall"
+
+	"github.com/grafana/grafana-app-sdk/logging"
+	"github.com/grafana/grafana/pkg/api/dtos"
+	"github.com/grafana/grafana/pkg/api/webassets"
+	"github.com/grafana/grafana/pkg/middleware"
+	"github.com/grafana/grafana/pkg/services/licensing"
+	"github.com/grafana/grafana/pkg/setting"
+)
+
+type IndexProvider struct {
+	log   logging.Logger
+	index *template.Template
+	data  IndexViewData
+}
+
+type IndexViewData struct {
+	CSPContent       string
+	CSPEnabled       bool
+	IsDevelopmentEnv bool
+
+	AppSubUrl    string
+	BuildVersion string
+	BuildCommit  string
+	AppTitle     string
+
+	Assets *dtos.EntryPointAssets // Includes CDN info
+
+	// Nonce is a cryptographic identifier for use with Content Security Policy.
+	Nonce string
+}
+
+// Templates setup.
+var (
+	//go:embed *.html
+	templatesFS embed.FS
+
+	// templates
+	htmlTemplates = template.Must(template.New("html").Delims("[[", "]]").ParseFS(templatesFS, `*.html`))
+)
+
+func NewIndexProvider(cfg *setting.Cfg, license licensing.Licensing) (*IndexProvider, error) {
+	assets, err := webassets.GetWebAssets(context.Background(), cfg, license)
+	if err != nil {
+		return nil, err
+	}
+	t := htmlTemplates.Lookup("index.html")
+	if t == nil {
+		return nil, fmt.Errorf("missing index template")
+	}
+
+	return &IndexProvider{
+		log:   logging.DefaultLogger.With("logger", "index-provider"),
+		index: t,
+		data: IndexViewData{
+			AppTitle:     "Grafana",
+			AppSubUrl:    cfg.AppSubURL, // Based on the request?
+			BuildVersion: cfg.BuildVersion,
+			BuildCommit:  cfg.BuildCommit,
+			Assets:       assets,
+
+			CSPEnabled: cfg.CSPEnabled,
+			CSPContent: cfg.CSPTemplate,
+
+			IsDevelopmentEnv: cfg.Env == setting.Dev,
+		},
+	}, nil
+}
+
+func (p *IndexProvider) HandleRequest(writer http.ResponseWriter, request *http.Request) {
+	if request.Method != "GET" {
+		writer.WriteHeader(http.StatusMethodNotAllowed)
+		return
+	}
+
+	nonce, err := middleware.GenerateNonce()
+	if err != nil {
+		p.log.Error("error creating nonce", "err", err)
+		writer.WriteHeader(500)
+		return
+	}
+
+	// TODO -- restructure so the static stuff is under one variable and the rest is dynamic
+	data := p.data // copy everything
+	data.Nonce = nonce
+
+	if data.CSPEnabled {
+		data.CSPContent = middleware.ReplacePolicyVariables(p.data.CSPContent, p.data.AppSubUrl, data.Nonce)
+	}
+
+	writer.Header().Set("Content-Type", "text/html; charset=UTF-8")
+	writer.WriteHeader(200)
+	if err := p.index.Execute(writer, &data); err != nil {
+		if errors.Is(err, syscall.EPIPE) { // Client has stopped listening.
+			return
+		}
+		panic(fmt.Sprintf("Error rendering index\n %s", err.Error()))
+	}
+}

pkg/services/frontend/index.html

@@ -0,0 +1,33 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    [[ if and .CSPEnabled .IsDevelopmentEnv ]]
+    <!-- Cypress overwrites CSP headers in HTTP requests, so this is required for e2e tests-->
+    <meta  http-equiv="Content-Security-Policy" content="[[.CSPContent]]"/>
+    [[ end ]]
+    <meta charset="utf-8" />
+    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
+    <meta name="viewport" content="width=device-width" />
+    <meta name="theme-color" content="#000" />
+
+    <title>[[.AppTitle]]</title>
+
+    <base href="[[.AppSubUrl]]/" />
+
+    <link rel="mask-icon" href="[[.Assets.ContentDeliveryURL]]public/img/grafana_mask_icon.svg" color="#F05A28" />
+
+    [[range $asset := .Assets.CSSFiles]]
+      <link rel="stylesheet" href="[[$asset.FilePath]]" />
+    [[end]]
+
+    <script nonce="[[.Nonce]]">
+      performance.mark('frontend_boot_css_time_seconds');
+    </script>
+
+  </head>
+
+  <body>
+    <h1>Grafana Frontend Server ([[.BuildVersion]])</h1>
+    <p>This is a simple static HTML page served by the Grafana frontend server module.</p>
+  </body>
+</html>