refactor: Review metrics endpoints (#1770)

Signed-off-by: Alexei Dodon <adodon@cisco.com>

pkg/api/config/config.go

@@ -340,6 +340,10 @@ func isOpenIDAuthProviderEnabled(config *Config, provider string) bool {
 	return false
 }
 
+func (c *Config) IsMetricsEnabled() bool {
+	return c.Extensions != nil && c.Extensions.Metrics != nil && *c.Extensions.Metrics.Enable
+}
+
 func (c *Config) IsSearchEnabled() bool {
 	return c.Extensions != nil && c.Extensions.Search != nil && *c.Extensions.Search.Enable
 }

pkg/api/routes.go

@@ -179,20 +179,8 @@ func (rh *RouteHandler) SetupRoutes() {
 	// gql playground
 	gqlPlayground.SetupGQLPlaygroundRoutes(prefixedRouter, rh.c.StoreController, rh.c.Log)
 
-	// setup extension routes
-	if rh.c.Config != nil {
-		// This logic needs to be reviewed, it should depend on build options
-		// not the general presence of the extensions in config
-		if rh.c.Config.Extensions == nil {
-			// minimal build
-			prefixedRouter.HandleFunc("/metrics", rh.GetMetrics).Methods("GET")
-		} else {
-			// extended build
-			ext.SetupMetricsRoutes(rh.c.Config, rh.c.Router, authHandler, rh.c.Log)
-		}
-	}
-
 	// Preconditions for enabling the actual extension routes are part of extensions themselves
+	ext.SetupMetricsRoutes(rh.c.Config, rh.c.Router, authHandler, rh.c.Log, rh.c.Metrics)
 	ext.SetupSearchRoutes(rh.c.Config, prefixedRouter, rh.c.StoreController, rh.c.MetaDB, rh.c.CveInfo,
 		rh.c.Log)
 	ext.SetupImageTrustRoutes(rh.c.Config, prefixedRouter, rh.c.MetaDB, rh.c.Log)
@@ -1860,11 +1848,6 @@ func (rh *RouteHandler) OpenIDCodeExchangeCallback() rp.CodeExchangeUserinfoCall
 	}
 }
 
-func (rh *RouteHandler) GetMetrics(w http.ResponseWriter, r *http.Request) {
-	m := rh.c.Metrics.ReceiveMetrics()
-	zcommon.WriteJSON(w, http.StatusOK, m)
-}
-
 // helper routines
 
 func getContentRange(r *http.Request) (int64 /* from */, int64 /* to */, error) {

pkg/api/session.go

@@ -113,7 +113,7 @@ func SessionLogger(ctlr *Controller) mux.MiddlewareFunc {
 				path = path + "?" + raw
 			}
 
-			if path != "/v2/metrics" {
+			if path != "/metrics" {
 				// In order to test metrics feture,the instrumentation related to node exporter
 				// should be handled by node exporter itself (ex: latency)
 				monitoring.IncHTTPConnRequests(ctlr.Metrics, method, strconv.Itoa(statusCode))