[ffapi] Renaming Metrics Server to Monitoring and Allowing Additional Routes

pkg/ffapi/apiserver.go

@@ -1,4 +1,4 @@
-// Copyright © 2024 Kaleido, Inc.
+// Copyright © 2025 Kaleido, Inc.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -61,9 +61,9 @@ type apiServer[T any] struct {
 	apiDynamicPublicURLHeader string
 	alwaysPaginate            bool
 	handleYAML                bool
-	metricsEnabled            bool
+	monitoringEnabled         bool
 	metricsPath               string
-	metricsPublicURL          string
+	monitoringPublicURL       string
 	mux                       *mux.Router
 
 	APIServerOptions[T]
@@ -72,10 +72,11 @@ type apiServer[T any] struct {
 type APIServerOptions[T any] struct {
 	MetricsRegistry           metric.MetricsRegistry
 	Routes                    []*Route
+	MonitoringRoutes          []*Route
 	EnrichRequest             func(r *APIRequest) (T, error)
 	Description               string
 	APIConfig                 config.Section
-	MetricsConfig             config.Section
+	MonitoringConfig          config.Section
 	CORSConfig                config.Section
 	FavIcon16                 []byte
 	FavIcon32                 []byte
@@ -99,8 +100,8 @@ func NewAPIServer[T any](ctx context.Context, options APIServerOptions[T]) APISe
 		maxFilterSkip:             options.APIConfig.GetUint64(ConfAPIMaxFilterSkip),
 		requestTimeout:            options.APIConfig.GetDuration(ConfAPIRequestTimeout),
 		requestMaxTimeout:         options.APIConfig.GetDuration(ConfAPIRequestMaxTimeout),
-		metricsEnabled:            options.MetricsConfig.GetBool(ConfMetricsServerEnabled),
-		metricsPath:               options.MetricsConfig.GetString(ConfMetricsServerPath),
+		monitoringEnabled:         options.MonitoringConfig.GetBool(ConfMonitoringServerEnabled),
+		metricsPath:               options.MonitoringConfig.GetString(ConfMonitoringServerMetricsPath),
 		alwaysPaginate:            options.APIConfig.GetBool(ConfAPIAlwaysPaginate),
 		handleYAML:                options.HandleYAML,
 		apiDynamicPublicURLHeader: options.APIConfig.GetString(ConfAPIDynamicPublicURLHeader),
@@ -142,7 +143,7 @@ func (as *apiServer[T]) Serve(ctx context.Context) (err error) {
 	}()
 
 	httpErrChan := make(chan error)
-	metricsErrChan := make(chan error)
+	monitoringErrChan := make(chan error)
 
 	apiHTTPServer, err := httpserver.NewHTTPServer(ctx, "api", as.MuxRouter(ctx), httpErrChan, as.APIConfig, as.CORSConfig, &httpserver.ServerOptions{
 		MaximumRequestTimeout: as.requestMaxTimeout,
@@ -153,20 +154,20 @@ func (as *apiServer[T]) Serve(ctx context.Context) (err error) {
 	as.apiPublicURL = buildPublicURL(as.APIConfig, apiHTTPServer.Addr())
 	go apiHTTPServer.ServeHTTP(ctx)
 
-	if as.metricsEnabled {
-		metricsHTTPServer, err := httpserver.NewHTTPServer(ctx, "metrics", as.createMetricsMuxRouter(ctx), metricsErrChan, as.MetricsConfig, as.CORSConfig, &httpserver.ServerOptions{
+	if as.monitoringEnabled {
+		monitoringHTTPServer, err := httpserver.NewHTTPServer(ctx, "monitoring", as.createMonitoringMuxRouter(ctx), monitoringErrChan, as.MonitoringConfig, as.CORSConfig, &httpserver.ServerOptions{
 			MaximumRequestTimeout: as.requestMaxTimeout,
 		})
 		if err != nil {
 			return err
 		}
-		as.metricsPublicURL = buildPublicURL(as.MetricsConfig, apiHTTPServer.Addr())
-		go metricsHTTPServer.ServeHTTP(ctx)
+		as.monitoringPublicURL = buildPublicURL(as.MonitoringConfig, apiHTTPServer.Addr())
+		go monitoringHTTPServer.ServeHTTP(ctx)
 	}
 
 	started = true
 	close(as.started)
-	return as.waitForServerStop(httpErrChan, metricsErrChan)
+	return as.waitForServerStop(httpErrChan, monitoringErrChan)
 }
 
 func (as *apiServer[T]) Started() <-chan struct{} {
@@ -177,11 +178,11 @@ func (as *apiServer[T]) APIPublicURL() string {
 	return as.apiPublicURL
 }
 
-func (as *apiServer[T]) waitForServerStop(httpErrChan, metricsErrChan chan error) error {
+func (as *apiServer[T]) waitForServerStop(httpErrChan, monitoringErrChan chan error) error {
 	select {
 	case err := <-httpErrChan:
 		return err
-	case err := <-metricsErrChan:
+	case err := <-monitoringErrChan:
 		return err
 	}
 }
@@ -242,7 +243,7 @@ func (as *apiServer[T]) createMuxRouter(ctx context.Context) *mux.Router {
 	r := mux.NewRouter().UseEncodedPath()
 	hf := as.handlerFactory()
 
-	if as.metricsEnabled {
+	if as.monitoringEnabled {
 		h, _ := as.MetricsRegistry.GetHTTPMetricsInstrumentationsMiddlewareForSubsystem(ctx, APIServerMetricsSubSystemName)
 		r.Use(h)
 	}
@@ -293,12 +294,20 @@ func (as *apiServer[T]) notFoundHandler(res http.ResponseWriter, req *http.Reque
 	return 404, i18n.NewError(req.Context(), i18n.Msg404NotFound)
 }
 
-func (as *apiServer[T]) createMetricsMuxRouter(ctx context.Context) *mux.Router {
-	r := mux.NewRouter()
+func (as *apiServer[T]) createMonitoringMuxRouter(ctx context.Context) *mux.Router {
+	r := mux.NewRouter().UseEncodedPath()
+	hf := as.handlerFactory() // TODO separate factory for monitoring ??
+
 	h, err := as.MetricsRegistry.HTTPHandler(ctx, promhttp.HandlerOpts{})
 	if err != nil {
 		panic(err)
 	}
 	r.Path(as.metricsPath).Handler(h)
+
+	for _, route := range as.MonitoringRoutes {
+		r.HandleFunc(route.Path, as.routeHandler(hf, route)).Methods(route.Method)
+	}
+
+	r.NotFoundHandler = hf.APIWrapper(as.notFoundHandler)
 	return r
 }

pkg/ffapi/apiserver_config.go

@@ -1,4 +1,4 @@
-// Copyright © 2023 Kaleido, Inc.
+// Copyright © 2025 Kaleido, Inc.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -22,8 +22,8 @@ import (
 )
 
 var (
-	ConfMetricsServerEnabled = "enabled"
-	ConfMetricsServerPath    = "/metrics"
+	ConfMonitoringServerEnabled     = "enabled"
+	ConfMonitoringServerMetricsPath = "metricsPath"
 
 	ConfAPIDefaultFilterLimit     = "defaultFilterLimit"
 	ConfAPIMaxFilterLimit         = "maxFilterLimit"
@@ -34,7 +34,7 @@ var (
 	ConfAPIDynamicPublicURLHeader = "dynamicPublicURLHeader"
 )
 
-func InitAPIServerConfig(apiConfig, metricsConfig, corsConfig config.Section) {
+func InitAPIServerConfig(apiConfig, monitoringConfig, corsConfig config.Section) {
 	httpserver.InitHTTPConfig(apiConfig, 5000)
 	apiConfig.AddKnownKey(ConfAPIDefaultFilterLimit, 25)
 	apiConfig.AddKnownKey(ConfAPIMaxFilterLimit, 100)
@@ -46,7 +46,7 @@ func InitAPIServerConfig(apiConfig, metricsConfig, corsConfig config.Section) {
 
 	httpserver.InitCORSConfig(corsConfig)
 
-	httpserver.InitHTTPConfig(metricsConfig, 6000)
-	metricsConfig.AddKnownKey(ConfMetricsServerEnabled, true)
-	metricsConfig.AddKnownKey(ConfMetricsServerPath, "/metrics")
+	httpserver.InitHTTPConfig(monitoringConfig, 6000)
+	monitoringConfig.AddKnownKey(ConfMonitoringServerEnabled, true)
+	monitoringConfig.AddKnownKey(ConfMonitoringServerMetricsPath, "/metrics")
 }

pkg/ffapi/apiserver_test.go

@@ -114,17 +114,17 @@ var utAPIRoute2 = &Route{
 func initUTConfig() (config.Section, config.Section, config.Section) {
 	config.RootConfigReset()
 	apiConfig := config.RootSection("ut.api")
-	metricsConfig := config.RootSection("ut.metrics")
+	monitoringConfig := config.RootSection("ut.monitoringConfig")
 	corsConfig := config.RootSection("ut.cors")
-	InitAPIServerConfig(apiConfig, metricsConfig, corsConfig)
+	InitAPIServerConfig(apiConfig, monitoringConfig, corsConfig)
 	apiConfig.Set(httpserver.HTTPConfPort, 0)
-	metricsConfig.Set(httpserver.HTTPConfPort, 0)
-	return apiConfig, metricsConfig, corsConfig
+	monitoringConfig.Set(httpserver.HTTPConfPort, 0)
+	return apiConfig, monitoringConfig, corsConfig
 }
 
 func newTestAPIServer(t *testing.T, start bool) (*utManager, *apiServer[*utManager], func()) {
 	ctx, cancelCtx := context.WithCancel(context.Background())
-	apiConfig, metricsConfig, corsConfig := initUTConfig()
+	apiConfig, monitoringConfig, corsConfig := initUTConfig()
 	um := &utManager{t: t}
 	as := NewAPIServer(ctx, APIServerOptions[*utManager]{
 		MetricsRegistry: metric.NewPrometheusMetricsRegistry("ut"),
@@ -135,10 +135,10 @@ func newTestAPIServer(t *testing.T, start bool) (*utManager, *apiServer[*utManag
 			// request and that's the "T" on the APIServer
 			return um, um.mockEnrichErr
 		},
-		Description:   "unit testing",
-		APIConfig:     apiConfig,
-		MetricsConfig: metricsConfig,
-		CORSConfig:    corsConfig,
+		Description:      "unit testing",
+		APIConfig:        apiConfig,
+		MonitoringConfig: monitoringConfig,
+		CORSConfig:       corsConfig,
 	})
 	done := make(chan struct{})
 	if start {
@@ -382,11 +382,11 @@ func TestAPIServerFailServe(t *testing.T) {
 
 }
 
-func TestAPIServerFailServeMetrics(t *testing.T) {
+func TestAPIServerFailServeMonitoring(t *testing.T) {
 	_, as, done := newTestAPIServer(t, false)
 	defer done()
 
-	as.MetricsConfig.Set(httpserver.HTTPConfAddress, "!badness")
+	as.MonitoringConfig.Set(httpserver.HTTPConfAddress, "!badness")
 	err := as.Serve(context.Background())
 	assert.Regexp(t, "FF00151", err)
 
@@ -408,15 +408,15 @@ func TestWaitForServerStop(t *testing.T) {
 }
 
 func TestBadRoute(t *testing.T) {
-	apiConfig, metricsConfig, corsConfig := initUTConfig()
+	apiConfig, monitoringConfig, corsConfig := initUTConfig()
 	as := NewAPIServer(context.Background(), APIServerOptions[*utManager]{
 		MetricsRegistry: metric.NewPrometheusMetricsRegistry("ut"),
 		Routes: []*Route{{
 			Extensions: &APIServerRouteExt[string]{}, // T does not match *utManager
 		}},
-		APIConfig:     apiConfig,
-		MetricsConfig: metricsConfig,
-		CORSConfig:    corsConfig,
+		APIConfig:        apiConfig,
+		MonitoringConfig: monitoringConfig,
+		CORSConfig:       corsConfig,
 	})
 	assert.Panics(t, func() { as.Serve(context.Background()) })
 }
@@ -425,5 +425,5 @@ func TestBadMetrics(t *testing.T) {
 	_, as, done := newTestAPIServer(t, false)
 	defer done()
 	as.MetricsRegistry = metric.NewPrometheusMetricsRegistry("wrong")
-	assert.Panics(t, func() { as.createMetricsMuxRouter(context.Background()) })
+	assert.Panics(t, func() { as.createMonitoringMuxRouter(context.Background()) })
 }