return /metrics before session middleware

pkg/api/api.go

@@ -6,7 +6,6 @@ import (
 	"github.com/grafana/grafana/pkg/api/dtos"
 	"github.com/grafana/grafana/pkg/middleware"
 	m "github.com/grafana/grafana/pkg/models"
-	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 // Register adds http routes
@@ -98,8 +97,6 @@ func (hs *HttpServer) registerRoutes() {
 	// api renew session based on remember cookie
 	r.Get("/api/login/ping", quota("session"), LoginApiPing)
 
-	r.Get("/metrics", promhttp.Handler())
-
 	// authed api
 	r.Group("/api", func() {
 
@@ -266,9 +263,6 @@ func (hs *HttpServer) registerRoutes() {
 		r.Get("/tsdb/testdata/gensql", reqGrafanaAdmin, wrap(GenerateSqlTestData))
 		r.Get("/tsdb/testdata/random-walk", wrap(GetTestDataRandomWalk))
 
-		// metrics
-		//r.Get("/metrics", wrap(GetInternalMetrics))
-
 		r.Group("/alerts", func() {
 			r.Post("/test", bind(dtos.AlertTestCommand{}), wrap(AlertTest))
 			r.Post("/:alertId/pause", bind(dtos.PauseAlertCommand{}), wrap(PauseAlert), reqEditorRole)

pkg/api/http_server.go

@@ -11,6 +11,8 @@ import (
 	"path"
 	"time"
 
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+
 	gocache "github.com/patrickmn/go-cache"
 	macaron "gopkg.in/macaron.v1"
 
@@ -165,6 +167,7 @@ func (hs *HttpServer) newMacaron() *macaron.Macaron {
 	}))
 
 	m.Use(hs.healthHandler)
+	m.Use(hs.metricsEndpoint)
 	m.Use(middleware.GetContextHandler())
 	m.Use(middleware.Sessioner(&setting.SessionOptions))
 	m.Use(middleware.RequestMetrics())
@@ -180,6 +183,14 @@ func (hs *HttpServer) newMacaron() *macaron.Macaron {
 	return m
 }
 
+func (hs *HttpServer) metricsEndpoint(ctx *macaron.Context) {
+	if ctx.Req.Method != "GET" || ctx.Req.URL.Path != "/metrics" {
+		return
+	}
+
+	promhttp.Handler().ServeHTTP(ctx.Resp, ctx.Req.Request)
+}
+
 func (hs *HttpServer) healthHandler(ctx *macaron.Context) {
 	if ctx.Req.Method != "GET" || ctx.Req.URL.Path != "/api/health" {
 		return